OBERHEIM SYNTH

hi all.  we've had an OB-8 in the studio for years and it's been non-working, we decided to 
get it back up to spec.  the battery had fried/died years ago, so we replaced it (not easy!) 
it makes no sounds, so i bought an oberheim programs data cassette.  then the manual 
calls for a certain type of old tape deck and mini cables so i got those. 

all hooked up and won't load the sounds.  i can hear the data signal through the OB-8's 
output, so i know it's going in and the OB-8 will output sound.

then i noticed the "cassette enable" switch did not do what it's supposed to, which is turn 
off all lights and turn on the "cassette" light, meaning it's in that mode.  

anyone suggest a simple thing that might need to be done, as far as the switch?  our 
bandmate who de-soldered and re-soldered the battery is a bit techy so just throw any 
knowledge my way please.

--- In oberheim@yahoogroups.com, "chthonic" <chthonic@...> wrote:
>
> hi all.  we've had an OB-8 in the studio for years and it's been 
non-working, we decided to 
> get it back up to spec.  the battery had fried/died years ago, so 
we replaced it (not easy!) 
> it makes no sounds, so i bought an oberheim programs data 
cassette.  then the manual 
> calls for a certain type of old tape deck and mini cables so i got 
those. 
> 
> all hooked up and won't load the sounds.  i can hear the data 
signal through the OB-8's 
> output, so i know it's going in and the OB-8 will output sound.
> 
> then i noticed the "cassette enable" switch did not do what it's 
supposed to, which is turn 
> off all lights and turn on the "cassette" light, meaning it's in 
that mode.  
> 
> anyone suggest a simple thing that might need to be done, as far as 
the switch?  our 
> bandmate who de-soldered and re-soldered the battery is a bit techy 
so just throw any 
> knowledge my way please.
>

First, make sure the cable harness from the cassette enable switch is 
plugged into the main circuit board connector correctly.  Check for 
any broken wires or dirty or corroded connector contacts.

ok, thanks for the help so far.  our resident techy band member has gotten the cassette 
interface light to come on and all others shut off as they should.

however, it still doesn't seem to be receiving the cassette signal.  i did as the manual said 
and watched the level on the 1980's cheapo tape deck i bought just for this purpose...as 
soon as the tone came in i pressed PLAY on the OB-8  it lit up, but no "banks lighting up 
in sequence".

in fact, i don't hear the screeching data sound coming from the OB-8's output.  i did 
awhile back when i was trying to boose the signal from a regular tape deck through a 
mixer headphone jack, but it was way quiet and distorted.  in fact, the regular sound i hear 
out of the OB-8 is a low-level buzz.

so here's a question i should've asked in the first place:  if the battery dies and is replaced, 
does that literally mean there should be NO SOUNDS in the OB-8?  that they MUST be 
reloaded from the tape, almost like samples?  or is the tape just a bunch of presets?



--- In oberheim@yahoogroups.com, "Paul White" <pjwhite@...> wrote:

>
> --- In oberheim@...m, "chthonic" <chthonic@> wrote:
> >
> > hi all.  we've had an OB-8 in the studio for years and it's been 
> non-working, we decided to 
> > get it back up to spec.  the battery had fried/died years ago, so 
> we replaced it (not easy!) 
> > it makes no sounds, so i bought an oberheim programs data 
> cassette.  then the manual 
> > calls for a certain type of old tape deck and mini cables so i got 
> those. 
> > 
> > all hooked up and won't load the sounds.  i can hear the data 
> signal through the OB-8's 
> > output, so i know it's going in and the OB-8 will output sound.
> > 
> > then i noticed the "cassette enable" switch did not do what it's 
> supposed to, which is turn 
> > off all lights and turn on the "cassette" light, meaning it's in 
> that mode.  
> > 
> > anyone suggest a simple thing that might need to be done, as far as 
> the switch?  our 
> > bandmate who de-soldered and re-soldered the battery is a bit techy 
> so just throw any 
> > knowledge my way please.
> >
> 
> First, make sure the cable harness from the cassette enable switch is 
> plugged into the main circuit board connector correctly.  Check for 
> any broken wires or dirty or corroded connector contacts.
>

Sounds like you don't have enough level out of the tape deck to make  
it work.  You must come out of the HEADPHONE jack, which you probably  
already know.  They were designed to work with portable cassette  
players so you could take them on the gig and the interface worked  
well providing you had enough output level.  Sounds like you are very  
close to making it work.

> so here's a question i should've asked in the first place:  if the  
> battery dies and is replaced,
> does that literally mean there should be NO SOUNDS in the OB-8?   
> that they MUST be
> reloaded from the tape, almost like samples?  or is the tape just a  
> bunch of presets?

There should be some sounds.  You should be able to grab a few knobs  
and dial in a "sound" manually.  If it won't do that, I'd suspect  
other problems.  The oscillators and filters, etc should all work even  
without the PROGRAM loaded in.  All the cassette data is, is the  
settings of the knobs for each patch.

Hope this helps and good luck with the old girl!  I sold my Xpander  
and miss the sounds of it in my music already.

Charlie

On Mar 13, 2008, at 12:13 PM, chthonic wrote:

> ok, thanks for the help so far.  our resident techy band member has  
> gotten the cassette
> interface light to come on and all others shut off as they should.
>
> however, it still doesn't seem to be receiving the cassette signal.   
> i did as the manual said
> and watched the level on the 1980's cheapo tape deck i bought just  
> for this purpose...as
> soon as the tone came in i pressed PLAY on the OB-8  it lit up, but  
> no "banks lighting up
> in sequence".
>
> in fact, i don't hear the screeching data sound coming from the  
> OB-8's output.  i did
> awhile back when i was trying to boose the signal from a regular  
> tape deck through a
> mixer headphone jack, but it was way quiet and distorted.  in fact,  
> the regular sound i hear
> out of the OB-8 is a low-level buzz.
>
> so here's a question i should've asked in the first place:  if the  
> battery dies and is replaced,
> does that literally mean there should be NO SOUNDS in the OB-8?   
> that they MUST be
> reloaded from the tape, almost like samples?  or is the tape just a  
> bunch of presets?
>
>

--- In oberheim@yahoogroups.com, Charles Massey <cmassey@...> wrote:
>
> Sounds like you don't have enough level out of the tape deck to make  
> it work.  You must come out of the HEADPHONE jack, which you probably  
> already know.  They were designed to work with portable cassette  
> players so you could take them on the gig and the interface worked  
> well providing you had enough output level.  Sounds like you are very  
> close to making it work.

yeah, i'm using the EAR jack on an old portable 1980s radio shack thing i got mint in box 
just for this type of application.


> > so here's a question i should've asked in the first place:  if the  
> > battery dies and is replaced,
> > does that literally mean there should be NO SOUNDS in the OB-8?   
> > that they MUST be
> > reloaded from the tape, almost like samples?  or is the tape just a  
> > bunch of presets?
> 
> There should be some sounds.  You should be able to grab a few knobs  
> and dial in a "sound" manually.  If it won't do that, I'd suspect  
> other problems.  The oscillators and filters, etc should all work even  
> without the PROGRAM loaded in.  All the cassette data is, is the  
> settings of the knobs for each patch.

i was afraid of that.  this means i'll have to take it to be serviced after all, which i was 
trying to avoid. 

had i thought of this in the first place, i wouldn't have bothered with the whole cassette 
thing.  presets are nice to start from, but i have enough understanding of this kind of 
analog synth to get to any sound i want from nothing.  of course, i'm afraid it may be 
unfixable, that the years-old moisture damage may have shorted out the circuits that 
actually make sounds - this happened with some other gear we had.


> Hope this helps and good luck with the old girl!  I sold my Xpander  
> and miss the sounds of it in my music already.

thanks, you've helped a lot by letting me know my next step (repair shop).  i've never 
played one, always wanted to since i was a kid.  will come back and let the group know my 
findings once it's been looked at.

well, i took the unit in and the quote is about $600-700 for repair.  this is more than my 
friend and i have, so we're going to pass for now.

turns out the unit DOES work...makes sounds...but only triggered through MIDI.  and 
possibly only intermittently.  the main problem is in the keys.  there was water damage 
some years ago, and they'd all have to be removed and cleaned.  

so screw it, we're going to put it on a stand with a MIDI keyboard and trigger it and see 
what kind of fun we can have.

as for the cassette interface, i'm at a loss.  the light comes on, the signal seems to be 
going in...but the banks don't seem to light up in response to any received information.  i 
may take a look inside and see if there's any more cleaning that can be done back there.


--- In oberheim@yahoogroups.com, "chthonic" <chthonic@...> wrote:
>
> --- In oberheim@yahoogroups.com, Charles Massey <cmassey@> wrote:
> >
> > Sounds like you don't have enough level out of the tape deck to make  
> > it work.  You must come out of the HEADPHONE jack, which you probably  
> > already know.  They were designed to work with portable cassette  
> > players so you could take them on the gig and the interface worked  
> > well providing you had enough output level.  Sounds like you are very  
> > close to making it work.
> 
> yeah, i'm using the EAR jack on an old portable 1980s radio shack thing i got mint in 
box 
> just for this type of application.
> 
> 
> > > so here's a question i should've asked in the first place:  if the  
> > > battery dies and is replaced,
> > > does that literally mean there should be NO SOUNDS in the OB-8?   
> > > that they MUST be
> > > reloaded from the tape, almost like samples?  or is the tape just a  
> > > bunch of presets?
> > 
> > There should be some sounds.  You should be able to grab a few knobs  
> > and dial in a "sound" manually.  If it won't do that, I'd suspect  
> > other problems.  The oscillators and filters, etc should all work even  
> > without the PROGRAM loaded in.  All the cassette data is, is the  
> > settings of the knobs for each patch.
> 
> i was afraid of that.  this means i'll have to take it to be serviced after all, which i was 
> trying to avoid. 
> 
> had i thought of this in the first place, i wouldn't have bothered with the whole cassette 
> thing.  presets are nice to start from, but i have enough understanding of this kind of 
> analog synth to get to any sound i want from nothing.  of course, i'm afraid it may be 
> unfixable, that the years-old moisture damage may have shorted out the circuits that 
> actually make sounds - this happened with some other gear we had.
> 
> 
> > Hope this helps and good luck with the old girl!  I sold my Xpander  
> > and miss the sounds of it in my music already.
> 
> thanks, you've helped a lot by letting me know my next step (repair shop).  i've never 
> played one, always wanted to since i was a kid.  will come back and let the group know 
my 
> findings once it's been looked at.
>