a technician friend of mine put two Cem wide body in my M1000 and they work good exactly the same

as the narrow type if can be of any interest

Martin

 

--- In oberheim@yahoogroups.com , Jill Saphic <jill_saphic@...> wrote:
>
> I agree, be happy!
> I just bought the last unused CEM narrow bodies an Ebay and they
> were not cheap! But they were a much more recent lot number
> than usual used chips, so I didn't mind too much I think...
> I have been searching my favorites file for an hour now,
> looking for an address to a Matrix synth website, that
> has an article that describes exactly this voice condition you're experiencing.
>   From what I remember, the guy said that there is a SPECIFIC chip that gets dirty,
> or oxidizes, or something like that. And that a lot of people sell their matrix's
> because of the voices going out, but in some cases it's this one chip.
> Not the CEM-3396s.
>  He said, if I remember correctly, that you pull this one chip out carefullly,
> gently clean the prongs, and put it back in, and the voices come back to normal.
> (if the CEMs are up to snuff.)
> He also wrote the procedure for cleaning the pins,
> but I can't find the site again! BUGGER!
> ALSO, this is a bit funny, he admitted HE is THE OBERHEIM FACTORY GUY
> that started the controversy of the Matrix 1000s not sounding as good as the other models,
>  He admits in this article that he MADE UP the spec difference between narrow bodies and wide bodies and put them in the OBERHEIM service manual as joke on someone he knew,
> but now everyone takes it to be completely true and defends it to their last breath!
> LOL!!!
> Anyway, that article in out there on an obscure oberheim site somewhere,
> maybe you can find it again and clean that specific chips prongs.
> just a thought if you get desperate...
>
>
> --- On Mon, 22/4/13, Peter MÃ ¶rck <peter@...> wrote:
>
>
> From: Peter MÃ ¶rck <peter@...>
> Subject: Re: [oberheim] Re: Matrix-1000: one voice faulty, replace chip
> To: oberheim@yahoogroups.com
> Date: Monday, 22 April, 2013, 1:20
>
>
>
>  
>
>
>
>
> You should be glad that it's not the CEM :)
> If the chip works in other slots and everything else seems fine I would assume it's something with the control circuitry for that voice that is the problem.
> I don't know exactly which IC controls what, but after taking a quick peek in the service manual I'd start looking at the 4051s (U202 and U203) and the 74HC32 (U404).
> If you have a scope you can verify their function. If not I guess you can just replace them and see if it helps.
>  
> BR,
> Peter
>  
>  
>
> ----- Original Message -----
> From: hawkberg
> To: oberheim@yahoogroups.com
> Sent: Sunday, April 21, 2013 9:37 PM
> Subject: [oberheim] Re: Matrix-1000: one voice faulty, replace chip
>
>  
>
> I managed to locate the chips, they seem to be in this order from left to right when facing the unit: 6-5-4-3-2-1....which I found out after accidentally swapping 4 and 5, thinking they were 2 and 3 :-).... but then I did swap the correct 2 and 3....but alas, no change at all: it still says voice 2 is the bad one :-(
>
> so I guess it is not the CEM chip that is the culprit :-(
>
> any other ideas
>
> is there any way to "disable" a voice so that I end up with a 5-voice instrument
>
> regards
> HÃ ¥kon
>
> --- In oberheim@yahoogroups.com , Peter MÃ ¶rck <peter@> wrote:
> >
> > I believe they're mounted in order 1-6 from left to right with the front panel towards you, but I think it's printed on the PCB as well.
> >
> > The Matrix-1000 is easy to open. I think it's just 2-3 screws on each side and then the top comes off easily.
> >
> > If you're buying a replacement 3396, please be aware that there are wide (600 mil) 3396:es also, which are used in the Matrix-6. They're usually called 3396W or WB or something like that.
> > The Matrix-1000 (as you will see) uses narrow (300 mil) ones.
> >
> > Also, be careful if removing the chips so you don't bend/break the pins. Either use an IC-extractor or a flat screwdriver and pry a bit on each end several times. Don't just bend it up completely on one side first, but take it bit by bit so it comes out "vertically" and not as if it's on hinges :)
> >
> > CEM3396 chips are obsolete but you can usually find them on specialized sites or ebay.
> > Judging by your name I would guess you're in Scandinavia :) So... European shops maybe...
> >
> > http://www.vintageplanet.nl/ seems to have the wide ones but not the narrow ones, so don't buy one of those.
> >
> > BR,
> > Peter
> >
> >
> > ----- Original Message -----
> > From: hawkberg
> > To: oberheim@yahoogroups.com
> > Sent: Sunday, April 21, 2013 11:19 AM
> > Subject: [oberheim] Re: Matrix-1000: one voice faulty, replace chip
> >
> >
> >
> > Thanks, good suggestion.
> >
> > I have to admit I havent dared to open it yet, I tend to start with the wrong screws and things fall aport :-)
> >
> > Will I easily be able to identify which chip is which And there is no soldering, only click-in or whatever the term is
> >
> > If it proves to be that chip, are CEM 3396 chip still available
> >
> > regards
> > HÃ ¥kon
> >
> > --- In oberheim@yahoogroups.com , Peter MÃ ¶rck <peter@> wrote:
> > >
> > > Before you replace:
> > > Try to swap the chip for voice 2 with that of another one and see if the problem moves as well.
> > > Sometimes just pressing down on the chips to reseat them in the sockets is enough.
> > > Removing them or putting them back might help as well.
> > > Just don't cuddle with your cat on a nylon carpet before you go in there...
> > >
> > > BR,
> > > Peter
> > >
> > >
> > > ----- Original Message -----
> > > From: hawkberg
> > > To: oberheim@yahoogroups.com
> > > Sent: Saturday, April 20, 2013 12:28 PM
> > > Subject: [oberheim] Matrix-1000: one voice faulty, replace chip
> > >
> > >
> > >
> > > Hi
> > >
> > > I recently bought a Matrix-1000, which the seller claimed was in perfect condition. When it arrived, I quickly discovered this was not so :-(
> > >
> > > One of the voices (or one of the oscillators of one of the voices ) is not functioning properly, the symptoms vary a lot from one patch to another.... from being completely silent to having a wrong pitch or other anomaly)
> > >
> > > I did return to factory defaults + ran calibration: no effect.
> > >
> > > Then I put it in "show voices played" mode, and the faulty voice always shows up at voice number 2.
> > >
> > > Any idea if this means I can have one of the CEM chips in it replaced
> > > Anyone with similar experiences
> > >
> > > grateful for any help or tip
> > >
> > > regards
> > > HÃÂ ¥kon
> > >
> >
>