Xpansions !

The Newsletter of the Xpander Users' Group	
Issue 8
Summer Solstice 1991


INSIDE THIS ISSUE :
The Xpansions Patch Format	
Questions and Comments
MIDI Keyboards for the Xpander
The XUG Patch Library
Programming Techniques
Review. The MIDImouse  Librarian
Review: 1000 Patches	
Review: Solid Sounds Vol. 3
Patches

THE RETURN OF XPANSIONS

From The Editor's Desk

     "Hello, everyone. It's me again. At last. So where have I been, anyway ? Well, 
that's a long story, and I really shouldn't wouldn't want to bore you with all the 
details. Suffice it to say that both Lionel and I have been really busy. So busy,  in 
fact, that it's a miracle this issue of Xpansions is even going out at all, a year late 
or no. . . "
     That was written in the fall of 1989, the LAST time I tried to finish Xpansions  
#8. Obviously I spoke too soon. I tried to make it clear when I established the 
XUG in 1986 that I would not ask anyone for money for any service the Group 
offered. Now you all know why; Real Life caught up to me in 1988, and things 
are even now too unsettled in my world to make any firm promises about the 
XUG. But I feel I have to try, and more importantly there are others who feel this 
way as well and who are willing to help me. So here we are again...
     At this point, I feel I owe some people an explanation, as if "Real Life" weren't 
enough. In 1988, Issues 6 and 7 of Xpansions were put out by Lionel with 
minimal assistance from me as I struggled with my thesis research at OakRidge, 
Tennessee. In l989 I finally returned home, and pieced together the mess my life 
had become in my enforced absence

Since then, I've gotten a lot closer to finishing my Ph.D., had an article published 
in the Computer Music journal, built up my studio and torn it down at least five 
times (never losing my Xpander, admittedly), been signed to the Synkronos 
independent space music label in Philadelphia with a first contribution to their 
sampler tape in Chuck Van Zyl's hands and a first full album in preparation, been 
yanked back to Oak Ridge in the midst of this for an even LONGER stay (would 
you believe most of 1990 ?), and assembled a group of electronic musicians from 
all over the USA and the UK to help me put out my first CD, which will be out on 
my own label later this year and shopped around for a deal after that. Oh, yes, I 
almost forgot: I got married, too. One other event that occurred between Issue 
Five and now, which has had far-reaching effects including the making of my CD 
and the reformation of the XUG, was my entry onto the Net. The Net is a generic 
term for the dozens of electronic mail, news, and information exchanges 
accessible to computer users world wide for the cost of a computer, a modem, and 
perhaps a registration fee. It includes but is not limited to PAN, BIX, 
CompuServe, Prodigy, FidoNet, ARPAnet, EDUnet, the Whole Earth 'Lectronic 
Link (WELL), BITnet, MILnet, and so on and so on.  The newsgroups and 
mailing lists of the Net connect a community of many thousands of computer 
users around the world and allow them to communicate easily and cheaply-some 
say TOO easily and cheaply, as the amount of wordy gossip that gets bandied 
around the Net is positively obscene at times. I have established a presence of 
sorts on two of the best-known of the electronic music groups there; 
rec.music.synth, the electronic music newsgroup distributed as part of the USEnet 
news feeds, and EMUSIC-L, a mailing list devoted to academically-oriented 
electronic music discussion run from the American University List Server in 
Washington, DC. I answer questions, give advice (some of it even useful), 
comment on other people's ideas, and generally make a nuisance of myself.
     This constant flow of information largely took the place of the XUG for a long 
time, as it was easier and more inundate and far more far-ranging than putting out 
a newsletter, and it more successfully satisfied the hunger for the company of 
other musicians that the XUG had partially addressed in the past. But it never 
completely replaced the XUG in my mind; the tight focus of the Group and the 
people I'd met there still had a strong pull for me, and I continued to promise the 
Net that I was going to get around to the XUG "any day now."
     Finally, Philip Galanter, of Galanter Productions, from whom you may have 
gotten an ad for the GenEdit/ Xpander package some time ago, publicly lambasted 
me in front of the Net, accusing me of stifling the growth of the Xpander 
community by promising a product I never delivered. He was right, of course; 
many people had come to the Xpander as it became available on the used market 
and analog synths in general enjoyed a renaissance based on their use in House 
and Rap music, and I was preventing them from seeking out the data they needed 
to know on their own. So I began putting Xpansions together and picking up the 
rusty pieces of the XUG.
     Phil was not just a heckler from the sidelines, however; he backed up his angry 
words with a good deal of support, collating the many patches the XUG has 
collected in the public domain over the years in a computer database and helping 
me prepare a patch tape for distribution to XUG members who want it

 He and I are also working with Dan Barrett (still working with a Matrix-12 as his 
main axe after all these years) and others to develop computer routines for patch 
sharing, so computer owners can skip the hassle of tape interfaces. Phil, Dan, and 
Kurt Geisel comprised my de-facto Editorial Team, new members and old getting 
behind me with everything from kind words to software aid.
     Lastly and most importantly of all, I was able to combine the power of the Net 
with the gloss and style of desktop publishing through the unstinting efforts of 
Adam Schabtach, our new Production Editor. Adam lives with his new bride in 
Boulder, and has a full DTP system on his Mac II as well as the capability of 
downloading plain ASCII files and reformatting them for the newsletter. He took 
over the job after Lionel, for reasons of personal dissatisfaction, quit the music 
industry entirely in 1989 and sold off his entire studio, including his beloved 
Xpander
     Well, I couldn't let Lionel's "baby," which I'd played with before on a visit to 
Philadelphia, just get sold off on the auction block, so I bought it myself and 
installed it in my studio with my own Xpander. About a year later, I gave it a 
good home with Adam, 
and he inherited Lionel's job along with his Xpander soon after that. And here we 
are, ready to take you all back into the world of OberLust again, just as the 
revitalized and stripped-down Oberheim division of Gibson Labs begins turning 
out new Matrix-12s and Xpanders again for the first time in years-still hand made 
and hand tested, still the best analog synths you can buy.
     "Well," you're probably thinking by now, "This history lesson is all very sweet 
and sentimental, but how is this stuff going to affect the XUG ?" Well, it'll affect 
our operations a lot, and in many ways. Because I now send plain-ASCII files to 
Adam for downloading and reformatting on his Mac, my writing and editing times 
no longer depend on the availability of a borrowed Mac (like my wife's over 
booked and under-powered 512e), and can be done piece meal as I find the time. 
This will cut down editing and prep time for issues to maybe a third or even a 
quarter of what it was before.
     The Net allows all of YOU to send in material via Email, and in fact I 
encourage you all to do so! Even sysex data can be sent in, if the format is agreed 
upon; plain text is a piece of cake, and need never be printed on paper until the 
issue is run off. If you have access to a computer-mail service that isn't an utter 
impossibility to use, USE IT. Learn how, if you haven't! This makes it so easy to 
send in material that it's ridiculous. Of course, if you have no such facilities, I 
won't turn up my nose at the U.S. Postal Service; our address is still 
MysTech/XUG,P.O.Box 81175, Pittsburgh, PA 15217-0675.
     Concerning future issues, we've decided that the amount of material we receive 
will directly dictate our schedule from now on. In other words, if we have a lot of 
stuff to publish, then we'll maintain the quarterly schedule we had for our first five 
issues or so. If, however, we are stuck with a dearth of new material, issues will 
be delayed until they're of decent size. For instance, with this issue we were able 
to clear up three whole YEARS' worth of backlog, and our submissions files are 
now empty. If there's to be another issue of Xpansions out any time soon, let's 
hear from you. Patches, tips, programming hints, reviews, questions, suggestions, 
you name it: the past seven issues of our newsletter only hint at the sort of 
contributions you can make. Your time and thoughts mean more to us than 
sending stamps or a check, so please help us out

And while we're on the subject, let me clarify once again our new stamp/check 
policy. As in the past, absolutely no renumeration of any sort is required of any 
XUG member at any time. In addition, we no longer require any stamps or 
International Reply Coupons be sent to us to help defray postage costs; they were 
too much hassle to keep track of and didn't lower the cost of putting out each issue 
enough to make them worth while. We do accept contributions, BUT as in the 
past, any monetary contributions must be in the form of gifts to me. Only a few 
people have helped us in this way in the past, and we're grateful to them (one 
Group member, who's asked to remain anonymous, sent us a large enough check 
to fund this issue completely, from laser printing to mailing, and he has our 
heartfelt thanks), but all of these contributions are voluntary. At the very most, 
you might be asked to provide a self-addressed stamped envelope or some IRCs if 
you're requesting so bulky like a cassette diskette, or stack of reprints. But if 
ANYONE calls or writes to you and demands any sort of money for a service 
supposedly related to the XUG, notify me at once! We do this for fun, and we 
need to know about it if anyone's trying to cash in on our work.
     If you're an old member and you've lost or damaged a back issue and want a 
replacement for it, write to me and I'll see what I can do. For newer members, 
though, we now distribute a compilation issue with all the non-dated material 
from Issues One through Seven. This is also available free of charge to anyone 
who needs it (within reason, of course).
     On side note, I've been asked about the XUG's role in the offering of discounts 
to XUG members for the sale of certain programmers' patch sets. The decision to 
do this rests entirely with the programmers, and they receive no renumeration 
from the XUG for this service. We applaud their willingness to help out their 
fellow musicians in this way.
     We're looking forward to getting back on track with this issue: we were a long 
time away, but now there's a lot to be said. Please feel free to call me if you'd like 
to share your thoughts-my new telephone number is (412) 521-3548. If a young 
lady answers, you haven't necessarily gotten a wrong number; more likely you're 
speaking to my (lovely) wife Suzanne. Anyway, that's enough reconstructive 
surgery. Time to clear up all the backlog, and get this newsletter rolling again !

Using The Keyboard Modes: A Tutorial
by Dan Barrett

     A few of our fellow XUG members are having some trouble understanding 
keyboard modes. Looking at the manuals for both Xpander and Matrix-12, I see 
that the explanations are very short, and contain few examples. This article is a 
tutorial to make you familiar with the differences between, and the advantages of, 
the diverse and powerful Oberheim keyboard modes.
     This article assumes you already know what a "zone" is. If you don't, please 
see page 47 in your Xpander Owner's Manual, or page 87 in the Matrix 12 
Owner's Manual. I will use the term "Xpander" to mean "Xpander or Matrix-12." 
Matrix-12 owners will have to substitute "12" instead of "6" in some of the 
examples.

WHAT IS A KEYBOARD MODE?
     First of all... what is a "keyboard mode?" When we select a keyboard mode, we 
are choosing how the Xpander will behave when we press a key. More 
specifically, we specify exactly which voice will play when a key is pressed. 
Now, keyboard modes are not the same thing as zones. A zone allows us to group 
voices together, to be played in a particular range on the keyboard, or on a 
particular MIDI channel. However, within each zone we still must choose which 
voices will play when we press a key. This is where keyboard modes come in!
     Let's use an example to illustrate. Suppose that all of your Xpander's voices are 
assigned to zone 1, stretching the entire length of the keyboard. This is the 
simplest zone setup on an Xpander. Now press a key on your keyboard. Question: 
Which voice in your Xpander will sound? Will it be voice number 1, or voice 
number 5, or perhaps all of the voices? The keyboard mode allows us to choose 
this.

     Here is a concise definition of keyboard mode: it is a method for choosing 
which voice will sound when a key is pressed in a given zone. If you are a 
computer programmer, it might be a particular voice that sounds, its dot lights up. 
Your voices are playing in ROTATION; first voice 1, then voice 2, and so on, up 
to voice 6, and then back again to voice 1. This is the purpose of ROTATE mode. 
Now, instead of playing one key all the time, play an ascending scale. As you 
move from key to key, the sound still changes for every note. No matter what you 
play, each key triggers the NEXT voice in the rotation from I to 6. Now try 
playing some chords, and watch the little dots again. Can you figure out what's 
going on? It's really the same thing-each key triggers the next voice in the 
rotation. But now, a 3-note chord might play voices 2,3, and 4; the next 3-note 
chord would play voices 5,6, and 1. For what purposes is ROTATE mode good? 
You have seen one purpose in the above example: having a different sound play 
each time you press a key. This difference can be subtle, too. Having 6 versions of 
the same patch, each slightly different, and then rotating through them, can make 
your patch seem more natural or life like. But it has other uses as well. For 
example, you might want to insure that voices will play (release) as long as 
possible after you let go of a key. In ROTATE mode, if you play voice 3, for 
example, it will not be reused until all the other voices have played in rotation.
     Next, let's look at REASSIGN mode. REASSIGN is very similar to ROTATE, 
but it has a subtle difference. Go back to your fancy multi-patch and set its zone's 
keyboard mode to REASSIGN. Now play an ascending scale. Once again, you 
should get a different sound for each note you play. This is the same behavior as 
in ROTATE mode. Next, choose any key on the keyboard and play it slowly and 
repeatedly. What happens? You should hear the same sound every time you press 
the note! Now choose three keys on the keyboard and play those keys only . Note 
that each key "retains" its particular voice. Watch the little dots in the 
PROGRAMMER display to see that this is really happening. What does this 
prove? REASSIGN mode causes each voice to "remain" at a particular key until it 
is needed at a different key. This is unlike ROTATE mode, which ALWAYS 
chooses the next voice in rotation. REASSIGN mode chooses the next voice in 
rotation unless there is "already" a voice "at" that note. What good is REASSIGN 
mode?

It is good for realistic piano patches, for one example. When you play a real 
piano, each key is associated with a different string inside the instrument. So it 
makes sense that a piano patch on your synth should be associated with a 
"different" voice. This is much like ROTATE mode. However, on a real piano, 
when you strike the same note twice, it uses the SAME STRING for both strikes. 
The second strike will tend to cut off the sound of the first. This is very much like 
what happens in REASSIGN mode.
     For our final polyphonic mode, we look at RESET. Its behavior is quite 
different from that of ROTATE and REASSIGN. To use this mode, go back to 
your fancy multi-patch and set its zone's mode to RESET. (Also, it will help if the 
individual single-patches of your multi-patch are sustained sounds. This is not 
necessary, but it will help you to understand this exercise.) With one finger, press 
a key and let it go. Then press a different key and let it go. Press many keys, one 
at a time, always LETTING GO of the key before you press the next one. What 
happens? Each key you press triggers the same single-
patch. More specifically, voice 1 always plays when you hold down one note. 
Watch the little dots in your PROGRAMMER display to see that this is true. 
Next, press AND HOLD one key with your left hand. Voice 1 will sound again. 
With your right hand, press a second key while still holding the first. The new key 
will trigger voice 2. Keep holding your first key (left hand), but press and release 
various other keys with your right hand, one at a time. Each key that you press 
plays voice 2, while your left hand holds voice 1. Watch the little dots again while 
you do this, to see what is happening. Now hold two notes down with your left 
hand, and press a third with your right hand. Voice 3 will sound. What is 
happening here, in general? RESET mode always causes the LOWEST 
NUMBERED FREE VOICE to play. A "free voice" is one that is not being 
triggered (its little dot is not lit up). Voice do NOT play in rotation. What uses are  
there for this mode? One possible use is with portamento (glide, or pitch lag). 
Suppose you set up a patch in which the lag processor is affecting the VCO 
Frequency, causing your pitches to glide from one to the other. This is the classic 
"portamento" effect. Play a three-note chord low on the keyboard. Let go, and 
then play a three note chord high on the keyboard. What happens? In ROTATE or 
REASSIGN mode, the first chord would play voices 1, 2, and 3. The second 
chord would play voices 4, 5, and 6. In other words, none of the voices would be 
the same in the two chords, so no "glide" would occur ! In RESET mode, both 
chords would use voices 1, 2, and 3, so the sound WOULD glide upward from the 
low chord to the high chord. Note: ROTATE is the default keyboard mode when 
your Xpander is in single-patch mode. For this reason, your portamento single-
patches may appear not to work! Switch your single-patch keyboard mode to 
RESET (press MASTER PAGE + ZONE and choose zone 1) if you want RESET 
to be your single-patch keyboard mode.
     Here is a summary of the polyphonic modes. ROTATE causes the voices in a 
zone to play in strict rotation. REASSIGN also plays the voices in rotation, unless 
you play a key which already has a voice "at" that key. RESET causes the lowest-
numbered free voice to play. Through careful choice of modes, you can tailor the 
way your multi-patches interact with the keyboard

MONOPHONIC KEYBOARD MODES
     Next, let's talk about the monophonic ("UNI") modes. They are called UNI-
LOW, 
UNI-HIGH, and UNI-LAST. In one sense, these monophonic modes all seem the 
same: they cause all voices in the zone to be played in unison, every time you 
press a key in that zone. You will experience their differences below.
	First, turn down your volume. (This will be louder than the polyphonic 
examples, since all voices will be playing at once.) Set your zone's mode to be 
UNI-LOW and play a key. All the voices in the zone will sound at once. Look at 
the little dots, and you will see that they all light up when you press one key. Set 
your zone's mode to UNI-HIGH, and then UNI- LAST, and playing notes again. 
Do you notice any differences? You might not ! I'll explain the differences, and 
then some applications.
     Set your mode to UNI-LOW again. Now press and hold two keys at once. This 
is a monophonic keyboard mode, so only one key can truly sound your voices. 
Which key wins? The LOWEST one that you are playing on the keyboard. Hold 
down six keys and listen: the lowest key is sounding all of the voices. Try the 
same experiment in UNI-HIGH mode. You will discover that the HIGHEST key 
is the only one that triggers all the voices. This illustrates the difference between 
UNI-LOW and UNI-HIGH modes; if there are several. keys held down, the 
lowest key (in UNI-LOW mode) or the highest key 
(in UNI-HIGH mode) is the "winner" that triggers the voices. Here is another 
exercise to feel the difference between UNI-LOW and UNI-HIGH, and it will lead 
us to understand UNI-LAST mode. In UNI-LOW mode, hold down two keys 
simultaneously. The low key wins. Continue to hold the lower key, but let go of 
the higher key. What happens to the sound? Nothing, because your lowest key has 
not changed. Let go of all keys. Hold down two keys again. Continue to hold the 
higher key, but let go of the lower key. Surprise ! The voices all jump up to the 
higher key. Why? Because it is now the lowest key you are holding. Keep holding 
that higher key, and press the lower key again. The voices jump to the lower key. 
Still holding the higher key, press and release the lower key repeatedly. Hear the 
voices jump from key to key, as your "lowest" key changes. Now, try the above 
experiment again, but in UNI-HIGH mode. You should get the exact opposite 
results. Releasing the lower key should have no effect, but releasing the upper key 
should cause the voices to jump to the lower key.
     Lets try doing some "hammer on" electric guitar playing in UNI-LOW mode. 
Set up your multi-patch so all voices are playing the same single patch. Make the 
sound very sustained even the "voice init patch" (press STORE-CLEAR) will do 
fine. Let go of all keys, and then hold down a "G" key in the middle of the 
keyboard. You will hold this key down throughout this exercise. Next, press and 
release the "F" key immediately below it, as quickly as you can, repeatedly. You 
should hear a trill. Stop. Now press and release the "D" key immediately below 
the "D" as quickly as you can, repeatedly. Stop. Finally, still holding the "G", 
alternatively press AND RELEASE the "F" and the "D", repeatedly, for true 
"Eddie Van Halen" action. (Make sure you release the keys completely, or you 
won't get the effect.) Now add some pitch bend...
        ... N Y E E E A A R R R M M!  WEEEEEEEOOOOOOOOO!!! 
Um... excuse me. You can use this general technique to "cheat" and play things 
faster than your fingers could play otherwise.
 Try playing the introduction to "Fooling Yourself" from THE GRAND 
ILLUSION by Styx in UNI- HIGH mode, or parts of Bach's" Toccata & Fugue in 
D minor" in UNI-LOW mode.

     Now, it's time to try using UNI-LAST mode. In this mode, it is not the lowest 
or highest key that triggers the voices. Instead, it is the LAST key (in time) that 
you play. Try our 2-key experiment above in UNI-LAST mode. When you release 
a key, the sound never jumps back to an old key. Only the LAST note you play is 
significant.
     Lets summarize the three monophonic ("UNI") modes. UNI-LOW always 
causes your lowest key to play the voices in the zone. UNI-HIGH always causes 
your highest key to play the voices in the zone. UNI-LAST always causes your 
last key to play all the voices in the zone.

COMBINING KEYBOARD MODES
     At this point, some people say: "So what? Why do we need all these different 
monophonic modes?" Well, the true power doesn't become apparent until you try 
using a monophonic zone layered with a polyphonic zone. Remember, each zone 
can have a different keyboard mode!
     Set up a multi-patch in which voices 1-4 play a sustained sound, and voices 5-
6 play a lead synth sound. Assign voices 1-4 to zone 1, in ROTATE mode, and 
voices 5-6 to zone 2, in UNI-HIGH mode. Set the limits for both zones to be 0 to 
127, so they overlap. We now have a monophonic sound layered, over a 
polyphonic sound. Play a chord, and what do you notice? The monophonic sound 
always plays the HIGHEST NOTE OF YOUR CHORD! As you play different 
chords, the lead sound follows your highest key. Instant melody! Now set zone 2 
to UNI-LOW and play a chord. The lead sound always plays the lowest note of 
your chord. Instant bass! Play with both of these setups for a while, and see what 
you come up with. Be creative! Personally, I use ROTATE layered with UNI-
HIGH to play the last section of "Song For America" by Kansas. Through clever 
fingering,  I can play the high melody at the same time as the string chords.
     Layering a polyphonic zone with a UNI-LAST zone is a little harder to control, 
in my opinion. With a little work, one can weave a melody among chords. For a 
really strange keyboard mode, layer three zones as in the following description. 
Assign voices 1-2 to zone 1, voices 3-4 to zone 2, and voices 5-6 to zone3. Set the 
limits on all zones to be 0-127. Make zone I UNI-LOW, zone 2 UNI-HIGH, and 
zone 3 UNI-LAST. If you play one key, you get all the voices. If you play two 
keys, you get voices 1-2 on the lower key, voices 3-4 on the higher key, and 
voices 5-6 on whichever key you played last. If you hold two keys and play others 
between them, you get only voices 5-6 on the "between" notes.

CONCLUSION
     My goal for this tutorial was to give you experience using the six keyboard 
modes. There are many different possible ways to use and combine these modes. 
Different people prefer different modes for particular styles of music or particular 
kinds of patches. I hope I have motivated you to experiment with keyboard 
modes. Most other synthesizers give you no choice over keyboard mode: often 
you're stuck with ROTATE for the entire instrument. Be glad you have a choice 
on your instrument ... let alone a choice for each zone! So, take this freedom and 
make the most of it!


How To Test An Xpander
by Mike Metlay

     For those of you who might be shopping for a used Oberheim in the future, or 
who have recently purchased one, here's a little test I wrote up. Maybe you'll find 
it helpful; the fellow for whom I wrote it certainly did.
     This test is in two parts. The first is relatively straightforward, and can be 
easily performed in any store; the second is more involved, and perhaps is best 
suited to when you have the instrument set up at home. Where's the dividing line 
between the two? You
turn off the offending voice with the appropriate button or knob. (If any voices 
didn't light up their LEDs before, you can now see if those voices were disabled 
here. If they were, turn them on now, and retune the instrument.) Now retune the 
instrument. If everything else passes, then you may have a bad voice chip. 
Fixable, but haggle like mad to get a better price: after all, you're now stuck with a 
5 voice synth!
     Now hit the MASTER PAGE button, then PAGE 2, then the button under the 
word SERVICE. (If the guy in the store isn't sweating yet, now he will be.) If 
everything on all the displays suddenly lights up, don't panic! Just hit PAGE 2 
again, and you'll see what happened: the DISP utility on the Service page uses the 
same button as the one you used to select SERVICE, and the button just double-
clicked. If that didn't happen, press DISP. Examine the LED displays for 
bummed-out segments: even one bad one in the wrong place can be a big hassle. 
When you're happy with what you see, press PAGE 2 to shut it off. (If the display 
segments all cycle through one by one instead of all coming on and staying on at 
once, this may indicate obsolete software; see below.) Now press the button under 
LEDS and watch the red LEDs all fight up, then cycle on and off in sequence, and 
look for bad ones. Do it again if you're not sure. Then hit the MEM button: it 
should then read ROM 0 OK, ROM 1 OK, ROM 2 OK, ROM 3 OK and put you 
back on the SERVICE Page. Hit VMEM: the display should read TESTING for a 
minute or two (it takes a while) and then read VMEM OK. Press Page 2 to get 
back to, the SERVICE page, and hit MASTER PAGE again to get out of that 
(You can hit the UNTUNE button if you want while in SERVICE page; this 
wrecks VCO tuning for some type of diagnostic. Retuning the instrument should 
line everything up again. Don't touch the two DAC-related buttons.

     Hit MASTER PAGE and PAGE 2, then select VERSION. The center display 
should read: MAIN PROCESSOR VERSION 1.2, VOICE VERSION 1.4, 
CASSETTE VERSION 1.0. Any numbers lower than these drastically lower the 
value of the Xpander, as its original software had a lot of bugs. (It also tells you 
that the instrument is a pre-ECC beast; a real find!) The software is upgradable, 
but in Oberheim's current state (they're retooling their service system) it could 
take a while to get new ROMS. (If you want to scare the salesman, ask to control 
the Xpander with a Roland keyboard; more on this in a moment.)
     Now, on the MASTER page, press MIDI. You'll be given a list of subpages to 
choose from: CHANNEL, CTRLS, ENABLES, SEND, RESET, MUTE. Hit 
CHANNEL. Is the set Basic Channel equal to the master keyboard's? Hit PAGE 2 
or MASTER PAGE and MIDI, then select CTRLS. Spin the knobs to set the 
controllers equal to whatever MIDI data your master is sending. For our example, 
set LEV 1 to BENDER, LEV 2 to 1, PED 1 to 7, PED 2 to 64, and PRESS to 
PRESSR. For a Yamaha synth, you might have to use 2 and 4 for the Breath 
Controller and Data Slider, etc. Use good judgment, and let the 
salesman help you: after all, you're not buying the master keyboard. Get back to 
the MASTERPAGE, then hit MIDI and select ENABLES. As you underline the 
various options or take their underlines away by hitting the appropriate  buttons, 
you should alternately enable and disable the Xpander's ability to receive Patch 
data, MIDI Controllers, SysEx, etc. Not all of these are easily testable; use your 
best judgment. The other MIDI options are SEND (don't do this unless the 
Xpander's MIDI out is hooked to a data storage device like a computer librarian), 
RESET (don't do this!), and MUTE. Hold a note on the keyboard, and press 
MUTE; the note should stop.
     Okay, now play a few notes and listen. No out-of-tune notes? No weird 
detuning or phasing problems? All righty. Now press VCO 2, and hold a note 
while you turn the knob under VOL to zero. One oscillator should fade away, 
leaving the other. Now press VCO 1, then PAGE 2, and push the button under 
TRI to underline it: you've added a Triangle wave form. Experiment with turning 
each wave on and off; make sure they sound okay. Press PAGE 2 again, or VCO 1 
again, to get back to Page 1. Vary the PW up and down, with only a pulse wave 
playing. Make sure that you hear the duty cycle change. Turn the FREQ, 
DETUNE, and VOL knobs and make sure each one works as advertised. When 
satisfied, leave the VCO full on, with on a Triangle wave selected.
     Repeat this procedure for VCO 2, with VCO 1 turned down. Then listen to 
both VCOs with triangle waves together: try detuning them and then tuning them 
and make sure their tunings line up without too much beating when they have 
identical settings. On VCO 2, listen to the NOISE output, and try SYNC. The two 
oscillators should hard-sync to one another. The other values on Page 2 control 
whether the VIB (global oscillator) controls the oscillator, or LEV 1 (your pitch 
bender), or KEYBOARD, or LAG. Shutting off KEYBOARD means the pitch of 
that oscillator shouldn't track; shutting off LEV 1 means the bender won't work. 
Satisfied?
     Go to the VCF/VCA page, and try out the various controls (Don't forget Page 
2). You'll notice that there's a period after FREQ and VCA 2. That means that 
they're being modulated. Hit the button under FREQ.

It should say ENV 1 and list a number. Turn the knob to make the number go up 
and down, and hear the effect on the frequency of the filter cutoff. Do the same 
for the VCA 2 modulation. (You exit a Modulation page by hitting the VCF/VCA 
button again.)
     Now to test the machine's response to MIDI control. There are two ways to do 
this: the easy way is to flip through the machine's presets and try out your 
controllers: velocity, pressure, etc. The hard way is to set up modulation routings 
in your initial patch; don't waste the salesman's time. You should assure yourself 
that each controller does something (although the bender may not bend pitch, the 
sustain pedal may not cause sustain, etc.: they can be set to do anything!). If  it 
seems that one controller isn't doing anything at all, recheck the MIDI CTRLS 
subpage and make sure the Xpander and master keyboard are talking to each other 
properly (If  PED 1 isn't set to 2, the DX7's Breath Controller won't do anything). 
This is where a Roland controller will fail if the synth's software is an old version: 
the sustain pedal won't sustain notes, no matter what, if the controller is a Roland, 
but it'll work fine for other makes. If all seems well, then you can be pretty sure 
that there's nothing flaky about your machine. If you want to use the analog 
PEDAL inputs on the back, set the PEDALs to PEDAL 1 and PEDAL 2 on the 
MIDI CTRLS page and try them with sustain and volume pedals. Polarities and 
throws vary a lot, though, so don't be too disappointed if the inputs don't work 
exactly as suspected. (Yamaha foot controllers won't work at all.) I'll also skip a 
description of how to test the CV and GATE inputs, the TRIGGER IN, and the 
chain pedal. You're not dumb.
     One last test: plug the amp into the MONO output, and be sure all voices 
sound with equal volume. Then go to the MASTER PAGE and select PAN. Plug 
the amp into first the LEFT, then the RIGHT outputs, and turn the knobs to vary 
the pan position of each voice. Make sure that each voice pans properly, and that 
there's no bleed
through on the LEFT output when the voice is set to the RIGHT, etc. The pan 
positions are: LEFT, LF2, LF1, MID, RT1, RT2, RIGHT, DIR. DIR should select 
the voice's individual output and remove it from the stereo mix. Verify this for 
each voice.
     Now, flip through the presets some more and enjoy the machine. You can 
check each little part of the architecture when you have a manual and some free 
time in hand. Have fun!
In the interest of saving space (and hence money), patches are presented in 
Xpansions in a compact layout. This article describes the "mold" we use to format 
the patch descriptions. It's a bit cryptic at first glance, but it's pretty easy to follow. 
Just keep in mind that the format follows the Xpander's displays and things should 
make sense. Save this article for future reference, since we will not print it in 
every issue. When you submit patches for publication (you are working on some 
patches for us, aren't you?) please use this format-it saves time and effort in 
publishing.
     To further the confusion, the patch format has been altered slightly from its old 
form. It's been mentioned to us by a number of people that our old format is in 
direct contravention to the familiar form of the manufacturer's MIDI Spec sheet, 
which uses "X" to indicate a feature not implemented and "O" to indicate one that 
is. For that reason, we have fixed our format to match this convention, so now an 
"O" means that a feature is enabled and an "X" means it is not

 The compilation issue's patches have been fixed in this regard, but for those of 
you with old back issues we'll provide a new printing of the patch format here. 
Use this format from now on (or, until someone comes up with something better-
any volunteers?)

Xpander Patch Editors/Librarians



Questions and Comments
----------------------------------------------------------------------------------------------------
-------
                                    Amiga                     Atari                  Mac                  
MSDOS
Galaxy                                                                                   L
Opcode

GenEdit                                                       E                       E
Hybrid Arts

MIDIQuest                    E                            E                       E                      E
Soundquest

Xor                                                             E                                                E  
Dr T's

Music-X                        L
MicroIllusions

Carter Burwell asks, "Does anyone sell a Mac-based patch editor for the 
Xpander?"
Well, we're glad you asked that. As it turns out, the past three years have been 
good to us XUGgies in that respect; the release of the Xpander/Matrix-12 MIDI 
System Exclusive Xpander Patch Editors Specification by Oberheim (write to me 
for a free copy, but don't be surprised if it takes a while) and the advent of generic 
editor/ librarian programs has resulted in a fair number of available options for 
supporting the Xpander" and Matrix-12 on a lot of machines.

I should point out that some of the programs on the following list are not yet 
available on all of the machines for which they are listed, and I should also point 
out that for most 
editor/librarians, no "official" Xpander editor exists as of yet. One exception is the 
Gen Edit package, for which Philip Galanter is marketing an Xpander editor as a 
value-added product (see his address in the Patches section). The XUG does not 
endorse any of these programs. 
There are probably a bunch of others as well, including some good public domain 
programs. The OberSuite is a set of useful PD codes by Dan Barrett for the Amiga 
that can dump, load, and analyze Oberheim patch data from the command-Line 
Interface; they're in beta test at the moment, but the release version should be 
available as you read this

 We'll be distributing some simple PD codes with our XUG patch sets, we hope, 
but anyone who has a working librarian or editor and who would be willing to 
write a review, put out disks in their program's format of patches from the XUG, 
or share an editor template for an existing program that they've written, should 
contact us. 		

Patch Exchange Via BBS
Jim Fischer has suggested that all members upload their current banks of 
programs to Genie,  the electronic bulletin board system, for networking and 
sharing patches. GEnie is one of many such BBSes available now; contact Jim on 
GEnie (his user name is J.Fischer7) and see what you can do with this idea. I 
recommend membership on an electronic network of some kind for every 
computer-using XUG member; at the very least, you can submit articles 
electronically to me, and patch swaps like the one Jim has suggested are easy to 
arrange. My Internet address is metlay@vms.cis.pitt.edu.

Life and Death in the Ober-Trenches
 Michael E.S. Murphy writes: "Welcome to the Ober-trenches (cue incoming 
artillery whistles and booms). We've got precious little food in these cans here and 
the bogies keep us pinned down pretty good but the Padre's still alive and there's 
still some in the guys in California with a few Curtis chips who can keep the old 
Xpander crackling .... It's,  it's not a real PROFESSIONAL briefing, Sarge, but 
Letts and Dunn, uh, well, uh.... they've gone to a better place, and we're all that's 
left uh, but we're real glad to see ya back, and we're all ready to FIGHT! RIGHT, 
BOYS?! Boys?" We'll return to `BLOOD ON THE MATRIX' after a word from 
our sponsor... It would seem we were missed] 	

Strange Behavior
Vincent Varco had an interesting lockup problem with his Xpander: the machine 
locked up and displayed only a lower-case "r" on the middle display. It stayed this 
way for two days, then returned to normal. Anyone else seen this sort of behavior? 
		

Synthesist Wanted
Steve McLinn of Case Music, a recording company and performing electronic 
band, says: "I'm currently looking for a talented synthesist, possibly a multi-
instrumentalist, to complete my ensemble. I already have added two 
percussionists to my own electronic / acoustic array for recording and performing. 
We currently tour concert halls, supporting my 14 albums. Call me if you're 
interested."


Matrix 12 Manual
John Riesnman asks: "How can I get a copy of a Matrix-12 owner's manual ?
That's easy, John: call Oberheim at 818-503-0123, ask for Faye, and order one. 
They
cost $20.

Rackmount Xpander ?
Bobby Jensen says, "I'd like to see a rack mount Xpander, and wondered if there
are any new software revisions available." The Xpander is not going to be 
released in a rack form, Bobby, but Oberheim is preparing to release an analog 
rack svnth called                     the OberMoog later this year. Call their support line 
at 800-765-4629 or watch the                     music media for details. The Xpander, 
while still produced on special order basis, is                     no longer being 
upgraded.

Used Xpander Wanted, Dead or Alive
K. Dulay is on the lookout for a used or damaged Xpander or Matrix-12 that he
can buy and refurbish himself, to add to his huge collection of Oberheim and 
other old                     analogue gear, including a Matrix-6 for which he needs 
patch tapes. KD also designs PC
boards for effects devices and synth modules, and collects old A/ DA, DOD, 
Electro-
Harmonix and Morley guitar pedals, as well as old or broken analog synths of any                     
stripe. (Hell, if he could ask in Electronic Musician, why not here?)

Software Versions
Andreas Schatzl, who might be familiar to some XUG members as the German 
columnist for Keyboard's "World View" column, has a pair of questions, one of 
which we can answer and another which might be illuminated further in future 
issues:
"What are the latest software revisions for the Xpander and Matrix-12, and how 
do they differ from other versions?"
 The latest software rev for the Xpander fixed a number of annoying bugs like
 losing sustain pedal data from Roland keyboards and generating incorrect 
transpo-
sitions in Multi mode, and added a few features like scrolling 
increment/decrement
 buttons. There is also rumored to be a beta-test version of the 12's software that 
fixes a couple of last remaining bugs, like the bleed through of Pressure 
modulation data into Pedal 2, but Oberheim's rep has informed me that it will be 
made available only upon public pressure, so write to Oberheim if you'd like to 
see this rev made available.
The latest official release of the software for the M12 still  contains at least two 
well-documented bugs: the External Trigger jack only affects six voices at a time 
(whichever six are displayed on the unit's front panel at the moment), and there is 
a problem with modulation bleed through between Pressure and Pedal 2: using 
one can activate modulations intended to be activated by the other. According to 
Jim Letts at Oberheim, the beta-test version of the software fixes all known 
Matrix-12 problems, but was never finalized and released because of a potentially 
dangerous bug of its own. Units with the beta software reportedly would lock up 
at random intervals, quite rarely but too often to allow the developers to release 
the information software officially. While the developers are to be commended for 
not allowing the distribution of software with a failure rate that they deem 
unacceptable, even if that rate is far lower than those of many synths currently 
marketed by less scrupulous companies in the industry, this leaves Matrix-12 
users in a sort of limbo, unable to obtain the software that would represent the 
highest development of the instrument.

However, our contact at Oberheim/Gibson assures me that with enough user 
pressure, the beta software might yet be released, and that individual users who 
would like to try the beta software and help pinpoint the lockups are welcome to 
try. Contact the Oberheim Technical Support Line at 1-800-765-4629 and ask 
how to make your voice heard.

Current Software Versions

		Main		
		Processor		Voice		Cassette
Xpander	1.2			1.4		1.0
Matrix 12	1.1			1.6		1.0

Thanks to Dan Barrett for supplying the M12 information.
Both voices (upper and lower) have the same version.

Xpanders On Record
Andreas's second question is: "What famous synthesists use the Xpander and 
Matrix-12 and on what records and soundtracks can they be heard?"
Wowie, this is a tough one to answer comprehensively ! I did a quick poll of the 
Editorial Staff via E-mail and we assembled the following list:
Tangerine Dream used Xpanders on Underwater Sunlight and possibly other
 albums in the years 1985 and on.
 
Steve Roach uses two Xpanders on his many albums, including Stormwarning, 
Empetus, and Dreamtime Return.


Allan Holdsworth used two Matrix-12s and an Xpander on Atavachron and Sand.
Keith Emerson used a Matrix-12 on Emerson Lake and Powell and tours with 
one.
The Nightcrawlers, a German-school synth band in New Jersey who are gaining
a strong following, used Xpanders and a Matrix-12 on Shadows Of Light.
Xpanders have also been heard on many recording by Philadelphia-area space-
music bands Xyl and Xisle, including Nuclear Winter and Novins.
Michael Hoenig used the Matrix-12 on his album Xcept One.
Trent Reznor of Nine lnch Nails utilizes the Xpander heavily on Pretty Hate 
Machine, his debut album.
Nitzer Ebb tours with an Xpander, and used one on their new album Showtime.
Vince Clarke, formerly with Depeche Mode and Yazoo, and currently with
Erasure, says the Xpander is his all-time favorite synth-presumably it can
be heard on newer Erasure albums, such as Wild! and The Innocents.
A Matrix-12 appears on several songs on Technotronic's debut album, Pump Up
the Volume. Herbie Hancock plays a Matrix-12 on his album Perfect Machine.
If you spot any more albums recorded with Xpanders and/or Matrix-12s, send us a 
note and we'll print another compilation in a future issue.
Allan Tamm asks, "I own but do not particularly enjoy using a Yamaha WX7. 
Has anyone got a wind controller for which the mechanics of the wind column 
and breath Wind Controllers pressure approximate that of some natural  
instrument they have played ? I can't answer that for myself, but the Synthophone, 
which is quite costly but based on a real sax, may show promise. Any other ideas 
out there?

The XUG in Europe 
Adam Glasser writes, "I would be happy to be available to answer questions on 
the
Xpander itself and on use of controllers and to help in the re-establishment of the 
XUG                     on this side of the Atlantic Ocean, but I think you would need 
someone with more time                     and enthusiasm for computers, as most of 
the Xpander owners are......       Basically, Adam  is willing to take up the position 
of European Representative of the XUG again, and provide materials and support 
for Europe who need materials from us, but is willing to turn over the position or 
ask the assistance of someone who has and uses a computer more regularly. I wish 
to add that Adam never really had a chance to do much for the XUG before it died 
the last time, but that in our new configuration an electronic mail link for our 
EuroRep would be a big plus. So for now, I'm going to hold the position open,        
and see if anyone as enthusiastic and considerably more qualified than Adams 
steps forward. Until then, I will handle all inquiries on XUG matters from all over 
the world.

A BBS for the XUG? 
	Vladimir Vooss is thinking of setting up a XUG BBS (computer-based 
bulletin
 board system for the uninitiated) for archival of articles, patches, information, 
message exchange,  and maybe even an Xpander chat line. This is still some time 
away from reality, if in fact  it does happen, but we would like feedback on how 
much such a service would be used and/or enjoyed.
Compatibility Problems
 	P. Caesar Walker reports a few glitches in attempting to get the Matrix-12 
to 
operate cleanly with his Roland MC500 sequencer. It seems that if one plays the 
Matrix-12 into the Roland with multiple active Zones, and the unit isn't in Mode 4 
(MIDI Mono), then the MC500 can get confused and lose note-off events, causing 
ye olde Stuck Note Syndrome. Does anyone know if a later software version or 
hardware kluge has been  worked out to solve this problem?

Foot Control
	Glenn Workman reports: "Regarding my own inquiry about a suitable 
rocker/
type foot pedal, I've found one, the Morley EV5-VC for about $75. If you can't 
find one call me. You need to get a split stereo 1/4" jack cable (stereo 1/4" on one 
end, two mono 1/4" on the other) for it to work for the full range of values."

Contacts In Europe
	Philippe Marais travels a great deal in Europe, and is always interested in 
meeting up with other XUG members on his travels

 He'd like to hear from anyone and everyone
who's willing to write or call, so he'll be able to stop in and say hello when he 
comes by.
 I'm passing this note along in response to a letter from Philippe where he 
described a tour across all of Europe, in which he was unable to reach a single 
XUG member in any city he tried!
	Eric Rehl reports: "Since I don't carry a computer around with me when I 
go to
different studios, it became important to me to have a lot more patches available 
inside the Matrix-12 than the 100 singles and 100 multis we are all used to. So 
pay attention, everyone, I have a solution which I would like to share.

Memory Expansion for the Matrix 12
     "My friend Joe Weitekamp, at dBm Electronics here in New York, has devised 
a modification that quadruples RAM storage in the Matrix-12! It will also hold 
patches in the edit buffer and will let you transfer them between the four banks of 
available storage space. He used a momentary push button switch which cycles 
between the banks, and installed a set of four LEDs to let you know which bank 
you are in. You can also use all the normal patch storage schemes now available 
(cassette and MIDI). It cost me $450, but could be different now; contact him for 
details. Two caveats: it hasn't been tried yet on an Xpander (although I called and 
asked him about that, and he said he felt it would be easily accomplished) and he 
wasn't sure whether he would offer it as a kit or require that the instrument be sent 
to NYC for him to do it himself.
     Joe does other custom work that may be of interest, including an amazing 
MIDI mod for the Memorymoog. He's very busy, so please don't call just to chat. 
If you're interested in his work, call or write: Joe Weitekamp, dBm Electronics, 
124 W. 19th St. New York, NY 10011 ph. (212) 645-2626
     DISCLAIMER:     Neither I nor the XUG will take responsibility for any non-
factory alteration of an Xpander or Matrix-12. Joe's reputation is good, and I'm 
thinking of letting him hotrod one or both of my Xpanders, but before you go 
sending your gear off to him, remember: you'll void your warranty, and may 
make it difficult for other Oberheim repair places to service your unit. Talk to Joe 
about the ups and downs of this operation before you make a decision, and if you 
decide to it, let us know how it turns out !


MIDI Keyboards for the Xpander

     Those of us who own Xpanders rather than Matrix-12s are perennially faced 
with the question of how best to control the beastie. It's true that the Xpander's 
many MIDI and CV inputs allow for a lot of flexibility, but there are a few areas 
where most keyboard controllers fall short. Release Velocity comes to mind 
immediately, as does multiple-MIDI channel transmit capability. Fortunately, 
we're seeing a lot of new keyboard designs that are flexible enough to deal with 
the Xpander on it's own terms, and there have always been a couple of older 
boards around to tell the Xp what to do.
     John Riesenmann has this to say about the Kurzweil MIDIboard: "It's not a 
roadworthy portable, though I have hauled it for a few sessions.

It's a great studio controller and has 88 weighted wooden keys with very light 
action. I'm using the 'Limited Edition' MIDIboard; the later version has a stiffer 
action. Pitch bend and modulation can be controlled by numerous programmable 
devices- two lever-action wheels, two 'data entry' type sliders, four switches for 
adjustable amounts of modulation, and inputs for two variable control pedals as 
well as a dual sustain pedal. I use a Boss FV200 volume pedal for modulation, 
and an Ensoniq dual pedal for sustain and other modulation effects. As an 
example, I can modulate one VCO on the Xpander with LEV 2, and control it on 
the MIDI board with wheel 2, slider B, switches 1-4, and the Boss pedal. All of 
these controls can be used interchangeably when they've been assigned to the 
same MIDI Controller Number. By setting the modulation amount for LEV 2 on 
the Xpander properly, I can produce a perfect fifth at maximum modulation.  On 
some patches, where I don't use LEV I for pitch bend, I can turnoff LEV 1 control 
of the VCOS, and use the MIDI board's wheel 1 and slider A to modulate VCF, 
VCA, ENV attack, LFO speed or amount, etc., etc. Since all controller 
information can be recorded as data in a MIDI sequencer (I use a Yamaha QX3), 
then patches can be programmed to evolve in real time without resorting to SysEx 
messages, thus saving memory, and can be played back at other studios without 
the need to transport the MIDI board. It's a pity the Xpander is only six-voice; 
however, if I can't pick up a used Matrix-12, then I'll get a second Xpander and 
assign each synth to half of a MIDI board split!"
     Mike Metlay (yeah, him again) uses an Oberheim Xk: 'The Xk was originally 
designed to control up to three different instruments simultaneously, and has a 
number of features that make it a powerful controller for the Xpander. It has a 61-
note unweighted keyboard with a very light and springy feel, velocity and release 
velocity, mono pressure, and the following expression controllers: two levers, one 
of which can have two functions in two directions and the other of which serves 
as a pitch bender, one data slider, and a sustain pedal (I use a fancy Korg 
negative- going version). The keyboard remembers 100 setups, each of which 
stores three keyboard Zones. Each Zone has it's own MIDI channel, note range, 
transpose value, patch number controller assignments, and spillover value, 
meaning how many notes can be played before they're bumped up one MIDI 
channel. I use mine with two Xpanders, and set the spillover to 6 on one Zone, so 
the first six notes are played by one Xpander and the next six by the other... better 
than a Matrix-12 ! The Xk has a simple arpeggiator, chord and hold features, and 
other nice utilities. Oberheim isn't making them any more, and you can often find 
them used for very little money. But beware! The Xk is an extremely finicky, bug 
ridden instrument, and ranges between functioning for years with nary a 
complaint to never working well at all. Mine's been in the shop six times, and as I 
type this I'm waiting for it to be sent back from Oberheim's factory, where they 
said they'd rebuild it for me. Let's see how long it lasts this time......
     Anyone else want to talk about how they control their Xpanders? It's not 
limited to keyboard controllers, either: wind and guitar synthesists, let s hear from 
you! And don't feel left out if you own a Matrix-12, folks; share your favorite 
keyboard setup tips with other Matrix owners while we poor Xpander owners 
drool with envy. Let's hear from you all!

The XUG Patch Library

     If you have a patch or set of patches that you are willing to trade, let me know 
at once. Phil Galanter is assembling an XUG Patch Library, which will contain all 
of the patches reviewed in these pages since Issue One! We'll assemble them in a 
form that any XUG member can obtain (tapes) as well as in formats for some 
generic editor programs (subject to the assistance of XUG members with the 
relevant software and the willingness to help), and in a form that will be readable 
by some FREE programs we will distribute on request. As of this writing, we 
have code to support the Amiga and Atari ST, and Mac and MS-DOS formats 
(with and without Microsoft Windows) will follow.
The collection includes some wonderful sounds from Alan Zipper, Peter Urbanek, 
and Art Springer, as well as the patches you've all been too lazy to pick out of our 
pages and program yourselves, including Ted Greenwald's FM Clavinet, Dan 
Barrett's auto-arpeggiator and a few really nasty surprises from my own chamber 
of horrors, like the one printed later in this issue, heh heh.
     I should note that although as of press time I have not been able to call and 
confirm this fact with Art Springer, the patches of his that will be included in the 
set will be the last he sends out; he has been forced by financial pressures to sell 
his Xpander. This will be a tragic loss for the XUG, as his patches were 
unquestionably unique and spectacular. But at least this last set will be available 
to all, a "best of" from his two collections reviewed in past issues. With any luck, 
the patches will be made available over the summer, and our next issue will have 
details on how to get a copy. Okay? Now send in those sounds, kids!


MIDI Delay Within a Multi Patch
by Glenn Workman

     These are some thoughts on using a Multi Patch to create a MIDI delay line. 
Create a version of the "echo" sound by setting all it's ENV delay values to the 
same amount. For example a setting of 43. is about 500 ms. of delay. Then select 
FREERUN on page 2 of those ENVS. On some sounds this may require some 
tweaking for the other values, but FREERUN is necessary for the ENV's to trigger 
if playing staccato notes. Next set up a Multi with the "original" sound layered 
with the "echo" sound. That's it.
     Variations:
1. The "original" sound and the "echo" sound can be the same timbre or 
completely different. For me this is the main use of this trick. An audio delay line 
can echo its input but not with a new sound. Brass echoed by Flute, Strings 
echoed by Bells, Piano echoed by... 
2. Use just the "echo" sound but MIDI'd to another synth. K5 echoed by Xpander, 
DX7 echoed by Xpander, Prophet echoed by ... 
3. Use this technique on just one VCO and build the echo into a SINGLE patch. 
On the Patch page, REZCHIM is an example of this.
 4. Build two (or more) "echo" sounds with successively longer delay-times and 
layer the whole mess. Brass echoed by Flute echoed by Strings echoed by Bells 
echoed by Piano echoed by...
(intentionally left blank)


Programming Techniques

Programming Challenges

     Steve Pesek asks: "I'd like to work out a means of controlling note sustain as a 
function of keyboard placement, so that low notes drone indefinitely but high 
notes can be played normally. Any suggestions?"
     My first thought would be to link ENV RELEASE to a Tracking Generator, to 
give long releases to low notes, but that's an imperfect answer at best. Anyone 
have anything more elegant?
     From Glenn Workman: "Can anyone else find the mysterious "page 3" that 
displays the names of 5 designers of the Xp/Ml2? It is the HI MOM!" page on the 
Xp and the "HI DAD!" page on the M12. I was sworn to secrecy when I figured it 
out, but that doesn't mean you can't try.

Macintosh Utilities for the Xpander and Matrix 12
by Glenn Workman

1. I have been programming little Hypercard utilities for the Xp/Ml2. The first to 
be finished is a conversion utility for overwriting the display of the Xp/Ml2 (like 
Jim johnson's C64 program in issue 4). It will transmit directly or store MIDI Text 
files for use with Southworth's Midi Paint. Includes error checking for proper 
ASCII values and text length, and a handy conversion chart showing typewriter 
equivalents for all the bizarre characters in the Xp/ M12 like the tv.set, the mobius 
flip, and the radiation symbol, just to mention a few.
2. I have all the Then set up the following pages:
Xpansions user patches in Opcode format if anyone wants them. If you don't use 
their librarian, I can send them in Midi Text format for use with MIDIScope or 
Southworth programs.
3. I have PD software including MIDIScope 1.41 (a data analyzer and crude bulk 
librarian), MIDI Control (shareware), and HyperMIDI (shareware), all with 
documentation. Anyone interested send me a Mac disk with your favorite PD 
software and I'll send one back with what you want.

 A Programming Discovery
 by Dan Barrett

 I have just been shown the most mind-blowing Xpander modulation. I wish I had 
discovered it myself, but I can't take credit for it. It was shown to me by Craig at 
the Guitar Exchange in Baltimore (a co-worker of XUG member Glenn 
Workman), who said he learned it from someone else. I took this "trick" and 
figured out what is going on; it is a powerful, general modulation technique! 
Here's the trick I was shown. My own analysis follows.
Many people know how to get an inverted keyboard" effect on the Xpander: just 
turn off KEYBD on the VCO Page 2 and modulate VCO FREQ negatively 
several times. But I have just been shown how to do it without using any of the 
Xpander's 20 modulations per patch. That's right: NONE of em! Interested? Here's 
how:

     Create a default voice OBERHEIM by holding STORE and hitting CLEAR.

FM/LAG:LAG IN - TRK 1,  LAG RATE - 0
TRACK1 : KEYBD .47, 39. 31 , 23 15 
VCF/VCA : FREQ = 127 .
	       p2: KEYBD OFF.
VCO 1 , 2 : (Adjust FREOs to taste),
     	       p.2: KEYBD OFF. LAG ON.

That's it ! My eyes popped when I did this myself at home. I couldn't believe it. 
It's the coolest Xpander routing I've seen in several years.
     Here's the patch, graphically: KEYBD->TRACKI->LAG->VCOs. Inverted 
keyboards are only one of the tricks you can do by putting Tracking and Lag 
between any modulator and the VCOs or VCF. The secret here is the use of Lag.
     This 'II certainly teach fellow Xpander-ites to check out those hardwired Page 
2 modulations more carefully ! Personally, I'd been ignoring them for the most 
part. Serves me right!


Review: The MiDimouse Librarian
by David Ziegele

     Note that this review; is a bit old, but may still be of use to some Atari users 
out there. My apologies to David for the delay in getting this out.
     I am in the Xpander/Matrix-12 patch business, so I'm always shuffling patches 
around on my Xpander and loading and saving patch sets as I fill orders. I'm also 
an electronic musician, and susceptible to that sudden craving for that certain 
weird patch that I saved on (I think) data cassette number 25....?

As a result, I have spent a lot of time listening to the fine whine of my cassette 
interface. So, when I finally coughed up the money for a computer recently (an 
Atari Mega2 ST, which is a fine product), one of the first things I wanted to buy 
was a patch librarian for the Xpander. The only one I knew of for the ST was from 
MIDImouse, are relatively well-established music software company from 
Oregon. At $50 list (with the price including a set of patches that sell for $25 
when purchased separately), it was hard to resist. However, after using the 
software package for about a month, I find that while it does make my life easier 
in some ways, there are many problems with it.

Overall Structure
     You can hold two files at a time in internal memory, one file holding a regular 
Xpander bank of 100 Singles and Multis and a second file of 100 Singles. The 
first is called a "bank" and the second is called "singles." You can very flexibly 
switch patches between the files or between either file and the synth. The files can 
then be saved separately to disk, with a double-sided 720K floppy able to hold 
about fifteen banks. All of the Single and Multi patch parameters can be displayed 
on the screen and printed. The program does not use GEM, so all commands are 
done with keystrokes instead of with the mouse.

Pros
     First, the program gives you great flexibility- it's a kick being able to quickly 
shift patches around between sound banks. For example, in about five minutes 
time, I was able to take all of the brass sounds from three separate patch sets (by 
copying them from their "bank" files into the "singles" file) , build a fourth set of 
only brass sounds (by sending them back to a new "bank" file in my desired 
order), and load that new set into my Xpander.
     Second, the program does everything pretty quickly. Menus are simple and 
logical. Shifts of single patches between files or between the synth and a file are 
just about instantaneous, and sending whole banks to or from the Xpander takes 
about twenty-five seconds.
     Third, the ability to print out patch lists and parameters from individual 
patches seems very useful (although I don't have a printer yet, so I  haven't been 
able to take advantage of this). And finally, after years of having data cassettes 
littering my studio, being able to store fifteen complete banks of Single and Multi 
Patches on a single floppy and quickly loading them when needed should be a 
Godsend. Which brings me to...

Cons
I can think of some features missing from this program that would be nice to 
have, but at this price its design features are more than sufficient. The problem 
that I have with this software is that I can't trust it. Think about that: what worse 
thing can you say about a tool of any kind?

First, on two occasions it has changed patch data in crucial ways after I transferred 
a bank from the synth to the computer, saved it on disk, and later restored it to the 
synth. Once, it added a keyboard modulation to one oscillator's pitch, causing an 
odd effect at 
upper registers, and the other time it lost the ENV 2 modulation of VCA 2, which 
of course resulted in a patch that never made a sound.
Second, when a bank is loaded into RAM, the software sometimes shifts the patch 
numbers up by one: 00 becomes 0l, and so on up to 98 becoming 99, 99 being 
lost, and 00 being blank. Third, it sometimes won't load all of the patches into 
from a bank into the Xpander. For example, patch 99 from one of my banks 
simply will not load into the Xpander from the ST, whether as part of a bank or as 
a single patch. Finally, whole-bank transfers from the Xpander to the ST fail on a 
fairly regular basis, and the MIDI mouse folks seem to have reconciled 
themselves to this, as they mention it in the manual and suggest turning off the 
Xpander and waiting a few minutes as a solution. Summary
     I still find the MIDI mouse librarian to be handy for shuffling patches around 
between patch sets and for quickly loading banks of sounds for and this is the key 
point non-crucial applications. When I can't afford to make any mistakes, as when 
I'm loading a patch set to save on cassette for a customer, I'm back to loading 
from tape. Also, I feel the need to make both disk and tape backups for new 
patches and sets that I save on disk using the program.
     Before submitting this review to Xpansions, I thought it only fair to call 
MIDImouse. I spoke to an individual named Norm, who acknowledged that some 
people have had problems with the program, but he placed the blame on bugs in 
the Oberheim operating system. MIDImouse made revisions to the software when 
earlier problems arose with the Xpander, which resulted in improvements rather 
than complete solutions.

He said that if the problems were in the program rather than in the synth, then I 
would see them every time, not intermittently. When asked what he would say in 
a review, he said that in addition to citing the program's virtues, he would describe 
the problems that can occur, attribute them to Oberheim, and offer the observation 
that many people have bought and used the program without being 
inconvenienced by the problems. (At least, not enough to call MIDI mouse)
     If you have an ST and you could make use of patch librarian software, where 
this leaves you as a potential user of the MlDI Mouse Librarian depends on your 
own answers to a few questions. Do you mind having to check if the numbers are 
properly assigned to the patches after loading a set from disk into memory. After 
transferring a bank to the synth, will it slow you down to play every patch to be 
sure that each one has been loaded, and loaded correctly? Will it be a problem to 
turn off your Xpander for a few minutes before sending a patch bank to the ST ? If 
your answer to those questions is "no," then this is the software for you! 
Otherwise, you should probably hang in there with your cassette interface until 
either MIDImouse debugs this thing or somebody else comes up with a better 
product.

Review: 1000 Patches for the Xpander

by Mike Metlay

1000 Patches for the Xpander (Actually closer to 1300; price $20.00. Available 
from Oberheim, 13345 Stacey St., North Hollywood, CA 91605.)
     This review is a cop-out. I want to say that right now, so as not to give anyone 
any other impression. In contrast to my usual attempts at thoroughness and care in 
doing these reviews, I am taking the coward's way out in my review of these 
sounds from Oberheim and only publishing a quick, cursory article. Why? 
Because I'm beat, that's why. There's only so much a guy can chug through in one 
sitting, and I have been floating in Oberheim patches for over a week now. 
Enough is enough!
     If Oberheim was trying to impress users with sheer quantity, they've 
succeeded. If they were trying to impress users with quality, they've also 
succeeded to a surprising degree. I knew ahead of time that getting through this 
patch set was going to be tough because of its volume; I had no idea that my 
difficulties were going to be massively compounded by the fun I'd have while 
listening to all of these sounds.
     Let's get the basics out of the way first. This very long data cassette contains 
two dumps, in order, of each of thirteen patch banks (Singles only, although the 
dumps have initialized Multis as well), introduced by a vocal announcement such 
as, "Xpander and Matrix-12 patches, F/X and Percussion, twice." I should really 
be able to recognize the voice on the tape; it MAY be Richard Bugg, but I'm more 
inclined to think that it's Dave Bertovic, the now departed ECC/Obie Customer 
Rep. The announcements are sloppy, and the gaps between announcement and 
data are quite short, so be ready with the PAUSE button. The thirteen banks 
contain between 60 and 100 patches for a total of just over 1200 sounds. There are 
repeats, although surprisingly few, and patch banks with less than 100 sounds are 
filled out with initialized patches.

The tape has obviously been high-speed duplicated, as its sound quality is poor; 
the Xpander's tape interface is amazingly robust, but even it gagged on a number 
of these dumps. You can improve your performance by fast-forwarding and 
rewinding the entire tape before use so it feeds smoothly, and by tweaking levels 
and tone controls a bit. Still, don't be surprised if you get the dreaded "ERROR IN 
SINGLE PATCH DATA" message. If so, don't panic; the tape may only have 
missed a patch or two. Try it again, and the holes will usually get filled in 
properly. Out of the 1300 patches in the thirteen banks, I lost a grand total of two 
patches irrevocably: not too shabby, really.
     The cassette comes with a booklet detailing the names of the sounds, organized 
by bank. The booklet is some help in checking if tapes have loaded properly, but 
has a few shortcomings: the patch names use ASCII punctuation marks in place of 
the many unusual characters in the Xpander's display and some of them have 
gaps, misnumberings and wrong names in spots. The worst offender is the second 
bank of factory sounds, which loads properly but has a largely unrecognizable 
listing. Still, this is a minor quibble.
     Okay, I hear you say. We get names and no other documentation, and the 
patches barely load. So why bother ? Well, we haven't discussed  the sounds 
themselves yet, folks, and that's where this collection's strength really lies. One 
could, I suppose, get indignant and argue that Oberheim simply threw 1000 
random shots out and hoped for a hundred hits or so. That might be a reasonable 
argument, if that's how the Matrix 1000 was programmed in the factory randomly. 
But I tend to doubt it. We know where these sounds come from, and so does 
Oberheim, and they make no attempt to imply anything other than what the 
cassette label says: these are the 1000 factory presets of the Matrix-1000, run 
through a computer program that translates SysEx from Matrix-6 format into an 
approximation of Xpander format. They're not randomly generated by a computer, 
as so many third-party sound packages can be. They were intelligently 
programmed and prepared for another synth with a slightly different architecture, 
and they lose surprisingly
little in translation.
     Sure, there's only four-pole lowpass filtering enabled, and no FM  on VCO 1, 
and maybe the DCO Click waveform IS missing. But for all those discrepancies, 
there are some dynamite sounds in this collection. I've barely gotten through half 
the banks, and I've found well over a hundred sounds that I like, and a good dozen 
or two that I consider spectacularly worthwhile and that's BEFORE I even start 
tweaking the sounds to my own tastes! The thirteen banks include eleven Matrix-
1000 banks, organized as follows: Woodwinds & Brass, Synthesizers 1 and 2, 
Keyboards 1 and 2, Basses, Strings, Leads, F/X & Percussion, and two "catchall" 
banks called Combo and Bonus, that essentially group together the patches that 
didn't fit into the above banks (they're organized alphabetically within each bank, 
pretty much). The other two banks are the two sets of Xpander /Matrix-12 factory 
presets, the second volume that most owners know and love with sounds like 
THUNDER and ISLANDS (still the best steel Drum I've ever heard from an 
Obie) and the much rarer first volume from 1984, with classics like BUGFARTS 
and THE BEAM. These sounds alone, taking advantage as they do of the 
Xpander's full power, are well worth the cost of the tape

     But the M-1000 sounds don't suffer by comparison, in general. They sound 
quite good with real VCOs behind them, they show a fairly comprehensive usage 
of controllers (Velocity and Pressure sensitivity on most patches, Levers and 
Pedal 2 on almost all them, Pedal 1 and Release Velocity on a few), and while one 
does get a bit bogged down after the eightieth string patch, the subtle variations 
and wild offshoots are a lot of fun to discover. Controllers veer away from the 
usual mold frequently: while the default for Lever 1  is always pitch bend, Lever 2 
doesn't always bring in LFO modulation of VCO frequency and Pressure doesn't 
always open the VCF. Pedal 2 acts as a sustain pedal most of the time, but also 
triggers odd effects in some patches. There are patches both mild and wild to be 
found in every bank, and there always seems to be another bank to audition, and 
another, and another...
     So forgive me if I stop here, but I still have a bunch of sounds to try out, and 
I'd rather be auditioning and noting which sounds I want to mutilate and put to my 
own nefarious uses than typing this review. I've said that I don't believe in using 
factory patches in my music, and I still don't. But for the price of this tape, I 
consider the jump-start to my ideas embodied in these sounds to be well worth the 
time and effort of listening to them.

Review: Solid Sounds Vol. 3
by Mike Metlay

Solid Sounds Volume Three (cassette of 100 patches; price $30 for one tape, $50 
for two tapes, $75 for three, $100 for all four, with a $5 per order discount to 
XUG members. Available from David Ziegele at Solid Sounds, 7207 45th St., 
Chevy Chase, MD 20815.)
     There are now four volumes of the Solid Sounds Xpander/Matrix-12 sounds 
available; David has informed me that he is no longer writing new ones, but that 
he will continue to make the four extant volumes available to all interested 
buyers. (We hope to be able to review Volume Four in our next issue.) David 
Zeigele's Solid Sounds patches are among the best-known of the available third 
party sounds for the Xpander and Matrix-12. Four volumes of these sounds are 
available from David, and he plans to keep them in stock for interested customers 
for the forseeable future. In the past, we have reviewed Volumes One and Two, 
and in the future we hope to review volume Four. This is the present, so it's time 
to review Volume Three.
     In brief, I feel that this set of sounds will please anyone who has dealt with 
David in the past, and demonstrates a representative, if not exceptional, level of 
quality in the Solid Sounds collection. These patches aren't light years ahead of 
the first two Solid Sounds volumes, but they're better than most of the other 
Xpander materials I've heard for sale by a hefty margin. As always, the patches 
come dumped onto a short, high-quality tape, with recording levels printed on the 
shell. The tape is packed with a letter of introduction, a few words of explanation 
about the Solid Sounds patches in general, and pointers on obtaining maximum 
effectiveness for a few of the more unusual sounds. There is also a complete 
listing of patch names, grouped by general category and flagged with codes to let 
the user know which Levers and Pedals are active in each patch, and whether 
Pressure is enabled anywhere. This listing is quite, thorough, and the few 
typographical errors from which it suffers are easily fixed by the user.
     Now, on to the sounds themselves: the categories are melody, Lead, Plucked, 
Pads, Brass, Strings, Keyboards, Percussion, Basses, and Miscellaneous. Each 
category has a good spread of sounds for every taste, although I found them a bit 
too "conventional" for my tastes. (But then again, I love Art Springer's stuff, so 
maybe I'm just too weird.) Oft he Melody sounds, a couple stand out as having 
particularly nice touches, like 8VA DROP, which has echoes that play back an 
octave lower than the played pitch. But for the most part the Melody sounds are 
somewhat straightforward for general use, as are the Leads, which I frankly found 
a bit too tame for my uses and too similar to one another as well, right down to the 
vibrato applied via Pressure. There were a couple of tasty exceptions here as well; 
NASTY 1 and PWM LEAD use controllers and pressure to alter harmonics and 
pulse width, adding grit and toughness to the sounds. The Plucked sounds are 
unusual in their Pressure modulation, which allows vibrato to be added to the faint 
tails of the envelopes. One sound, called BLIPIP, has a nifty feature similar to 
something I've experimented with in the past an echo that's controllable from 
Pedal 1 on the sound.

The Pads are few in number but exceptional in character, with the sort of evolving 
timbres that make sampler users keep an analog synth on hand- filter sweeps in 
PAD 6, PWM via Pressure on PWM PAD, octave FM sweeps on RIPPAD 1, and 
a long and complicated enveloping on PADAROO that just sort of carries you 
along. Great stuff! The Brass sounds are fairly standard, but cover the gamut of 
good Xpander tonalities with a fair representation. David includes LIPS, a sort of 
spit-blip that he recommends for layering with the more sustained patches in 
Multis. The String sounds are also conventional but cover a lot of bases. I find the 
vibrato on these to be a bit excessive, but that's easy enough to fix. One of these 
sounds, RIPPLES, uses the lag processor to produce a fascinating timbral 
evolution. The Keyboard sounds include some straightforward pianos and organs, 
with no real standouts.
     Where the Solid Sounds patches really shine, though, is in the Percussion, 
Bass, and Miscellaneous categories. These form a uniformly excellent collection 
of sounds ranging from the imitative to the imaginative with barely a clinker in 
the bunch. The Percussion sounds include BLUMBAM, a bizarre neo-steel-drum 
sound, H20BOWLS, a sort of water gong, and THUMBPERC, an organic and 
arresting marimba imitation, among many others. Besides the Basses for live 
playing, there are three patches designed for use in sequencer basslines, where 
controllers alter the filter settings as the sound chugs along in the style of old 
Tangerine Dream modular synths-lovely ! And the Miscellaneous patches, besides 
being a load of fun to listen to and play with, are tremendous learning tools for the 
neophyte and Xpander-literate expert alike. Check out LAGLEVER for an 
excellent use of the Lag processor, and note the few Multi Patches included to 
make use of combined Miscellaneous sounds. David has sidestepped his normal 
policy of including no Multis to give some useful and instructional examples here.
     Volume Three upholds the Solid Sounds commitment to quality and beauty for 
which the first two volumes were noteworthy. If you're after sounds that are both 
instructive and immediately usable in a wide range of home studio or professional 
applications and are amenable to quick tweaks to make them uniquely yours, you 
could do a lot worse than to give these patches a try.
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