I agree with most of your concerns below, but if I have 18 hp to fill in my Doepfer rack, I have to know what the size of any particular module is. You can usually figure it out, so this is a fairly minor point, but there is some basic info you want to see when you're reading a module description.
Bryan
>>> drmabuce@yahoo.com 08/29/06 5:35 PM >>>
and a few 'how to's....
--- In wiardgroup@yahoogroups.com, "Robair, Gino" <grobair@...> wrote:
>
> If you¹re going to try to get modular makers to agree on something, you
> might as well try to get a consensus on how many planets are in our
solar
> system...
>
[Doc trudges to the parole check-in window, registers his ankle
transmitter and signs the form that attests that this post will
contain no references to the clergy of any religion nor will it refer
to acts of cross-border aggression among any sovereign nations. Then
he takes his seat in the chair at the front of the row where moderator
Mike can reach him with the flyswatter without getting up from his desk.]
Hi All
Sorry but Gino's allusion to the IAU convention got me thinking*
(Mike reaches for the flyswatter)
The fact that form factor has been allowed to become a
balkanizing issue in the modular market* for the SECOND time in my
life *. is a hot button on my rapidly aging dashboard.
In my life, different form factors are, at worst, a mild
annoyance and my experience is that the rewards for becoming
`front-panel-multilingual' far outweigh the inconvenience. That said,
i hasten to add these two disclaimers:
-i `m firmly on board with Bryan's wish that all the makers would
prominently publish the power supply specifications for each module
they sell , if not in a common format, at least with a bare minimum of:
-voltage requirements
-positive current consumption
-negative current consumption (if the power supply is bipolar)
In this `golden age' of analog modulars when the everyman can afford a
`Tonto system' , the users are expected to frame-out their own racks
and wire them for power. This requires that the users work out
differences in voltage levels , mind the polarity, and distribute
ample current. The least the makers could do is provide us with clear
easy-to-find specs to help us with this task.
-divergent form factors for DC power-supplies are not trivial and i do
favor standardization in the area of DC power connectors.
John Blacet posted an interesting `defensive-driving' approach to the
problems caused by divergent power connection systems here:
http://www.blacet.com/tech.html
under the topic heading:
"Protecting Modules from Power Supply Problems...."
but if we move from the back of the rack to the front panel, my
position changes significantly.
My rig includes eighth, quarter, banana and even some pin-jacks
(Paia). i have DC rails at +/-15v, +/-12v, 9v, 6v and 5v. It all
works together very nicely. i will confess that i'm exorcising a pet
peeve here but one of the reasons that i don't participate in most of
the broad forums anymore is that i just can't take the endless
laboring of panels and form factors seriously anymore. Please don't
get me wrong , i realize that the human interface is not trivial.
Ergonomics is as important as it is subjective. But long before i'd
embarked on my DIY odysseys i was patching my 15v,1/8" Arp 2600 into
my 12v banana Serge panels . i did this with barely any thought or
trouble and no soldering skills, i used very short alligator clips for
years before i made my converting mult box. As much as i'm tempted to
vent my spleen and indulge in conspiracy theories about who stands to
profit by inciting baseless hysteria about differences in mere
panel-features, i've decided it might be more constructive to simple
describe what i did *.. BEFORE i was the lucky beneficiary of guidance
from some generous techs (you guys know who you are)
[ Before i begin , experience compels me to yet another tiresome
disclaimer:
i voluntarily choose to ignore all the well-meant `help' that will
be offered by the gold-buying, XLO-swabbing, cable-focused audiophiles
out there. Guys,* (and so far, every one of you seems to be male (and
bald) ) *every person must find his own S/N ration just as he or she
must find their place in the universe*. Your advice is of no use to me
until you have walked the miles on the noise floor of MY little studio
in MY moccasins*. Thanks , but no thanks. ]
1/8" to ¼" is EASY:
Shielded RCA cables are practically free. By 1987 i had amassed a
large cardboard box of'em, all still in plastic bags from long
discarded stereos. i bought 50 RCA female to 1/8" male adapters and
50 RCA female to ¼" male adapters. Now i had `modular cables' i could
make 1/8" to ¼" or extra ¼" to ¼" or 1/8" to 1/8" (not to mention the
odd ¼" or 1/" to RCA) as i needed them. The quality was `consumer'
and thus, disposable, and i treated them so. When any component of
the system failed, i didn't even waste time with a test* i `retired'
and replaced it.
1/8" or ¼" to banana:
It's not as easy as the shielded interchanges but it sure ain't rocket
science either!
The basic rules are :
Connect the signal grounds (0 volts) of the systems together.
the sleeve of a shielded plug is the signal ground and there
are many other contact points for it. Signal ground for the banana
system is `on there somewhere'. If your supplier won't tell you where
it is you can still tap it. Use the ground of the two-conductor
shielded output jack. It doesn't matter where you tap it on the two
systems as long as each system is tapped SOMEWHERE and connected with
the other system
After the grounds are connected , then only the tips of the
shielded jacks need to make contact with the banana jacks. i used
clip an alligator clip to the tip of a shielded jack and i clipped the
other end to the metal part of a banana jack. That's admittedly pretty
improvisational and i soon built a large RCA to banana mult.**
(remember the modular cable concept) But the alligator clip method
worked with no soldering .
i also see a lot of hand-wringing and worry about `blowing up
my 12 volt doepfer with a 15 volt Wiard'. At a far-reaching
extrapolation of the term `theoretically' that scenario is possible.
But as a practical matter , in the confines of commercially offered
modules, it `s just not a concern.
Within the aforementioned constraints, the worst that can happen
is that a patch will have no effect , or it will behave like the
effects of patching a CV to and audio point. You might not get what
you expect but you won't hurt your module. This is because BEHIND THE
PANEL the makers have achieved something resembling a* `consensus'! (i
dare not utter the blasphemy of `standard') . It is simply this. Every
maker with which i'm acquainted, designs their circuits in a way that
keeps every output , whether CV or Audio to within +/-10 volts *OR
LESS. What this means to us civilians is that any thing that comes
squirting out of your 15v Wiard is not going to exceed +/- 10 volts
and the same goes for your 12v doepfer. Even in the event that an
accidental condition occurs, every commercial schematic i've seen
reveals that the makers are smart and cautious enough to put
components in the INPUT paths of their circuits to protect them from
accidental over-voltage conditions (and irresponsible gonzo DIYers ,
like myself)
Now, many of your outputs will be LESS than 10v (standard audio
tends to swing from +5v to -5v and that's no problem at all). The most
common signals that suffer from incompatibility problems are
gate-signals. For those of us old-schoolers who remember the Hatfield
vs. McCoy feud between Moog's S-triggers and Arp's V-triggers this
modern discrepancy seems trivial, and i find that the majority of
makers use a 5v threshold for gates. Just keep in mind that you won't
hurt anything with too LITTLE voltage , at worst it just won't
trigger. There are numerous small utility modules that can be used to
correct this problem.
These rough and ready methods have allowed me to interconnect
among every format available without paying the makers to make custom
mults, (and waiting for them to feel like getting around to such
admittedly drudgerous production)
As for power supplies, a few basic rules of thumb apply* but
know ye this:
You CAN fry your module (or worse) if you guess wrong with the DC
supply-rails.
The rules of thumb are pretty simple:
Know the VOLTAGE that your module needs. (Never guess* go to
the maker for the correct information)
For Voltage/V :
more than the rated amount is bad*REAL bad* don't even think
about it!
For Current/Amperage/ma:
more than the rated amount is good.
Voltage and Current flow in different ways. The tango between
these two phenomena is almost poetic in it's precision and beauty *.
But that poem will end with the line "And then my expensive shit
popped and went dark" if you mix them up!
A very practical and homespun tech (who owned my local radio
shack) explained it to me like this when i was 12 years old. Voltage
PUSHES it's way in , so you never want to have more than your gadget
can handle*.but your gadget PULLS only the current it needs, so you
all you have to do is make sure that there's ENOUGH , if you have too
much current , it will just stay quietly in the pool.
This `plumbing' analogy kept me out of trouble for a couple of
decades until other generous souls refined my understanding. The only
thing i'd add is that it is also bad to have insufficient current for
your module(s) because your power supply will run itself hot trying to
supply it.
Polarity is also important . Most modern modulars use `bipolar `
DC power. Despite the usual interpretation of `Bi" Bipolar DC uses
THREE wires to connect. A +(positive) wire, A * (negative) wire and a
Ground (0 volts) wire. Know which is which (again* don't guess) and
mind them well because this is the most common way that modules turn
into EX-modules! This is one area where we ALL long for a *. Well*
you know* * the "S"-word. A universal color code would be a boon to
everyone (except the poor color-blind) but at least each maker that
i've seen keeps consistent within their own rules . Wiard codes Red
for + , Black for * and Green for Ground.
So there it is* a very personal compendium of home remedies to
help you survive and even flourish in the rich diversity of formats.
It's not meant to be complete or comprehensive but it's a start. My
hope is that others will contribute the details of their own survival
strategies. Also i apologize for the tome-like length and the
attendant misspellings (i ain't no typist either!) and i thank any
reader for their patience.
Behind the panel, these modern modules are much more alike than
different . It's a shame to squander the benefits of such a rich field
of electrically compatible choices on account of mere mechanical
connectors.
May you all swing like Tarzan in the patch cord jungle!
-doc
** it's sort of visible on this page
http://www.musicsynthesizer.com/DIY/Mike/DrMabuse.htm
third picture down, behind the assimilated C64. Note the green ground
banana jack at the bottom
PS: Hey Gino! According to the new IAU definition , if i gain another
15 lbs , -i'll- be a planet! Judging by the Prague convention, the
Astrologers now not only look smarter and more dignified.. they even
look more OBJECTIVE!
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