Sequential circuits samplers

Hallo,

I wonder if anybody is aware that there are two versions of cem chips that could be inside your p2000 ?

I have found out before and encountered the differcene again.

I have 1 p2002 rev A voiceboard with cem 3379 /8708

and another p2002 rev B voiceboard with cem 3379 /6833    

I wonder if these chips are interchangeable ?
any comment appriciated.

kind regards,
David

Hi David,

I have two different 2002s and the boards and chips are not interchangeable.
I tried to change them and it doesn't work.
Even exchanged the complete board and this doesn't work as well...

Best

Thomas

On Feb 27, 2012, at 8:50 PM, dd_62622 wrote:

> Hallo,
> 
> I wonder if anybody is aware that there are two versions of cem chips that could be inside your p2000 ?
> 
> I have found out before and encountered the differcene again.
> 
> I have 1 p2002 rev A voiceboard with cem 3379 /8708
> 
> and another p2002 rev B voiceboard with cem 3379 /6833    
> 
> I wonder if these chips are interchangeable ?
> any comment appriciated.
> 
> kind regards,
> David
> 
> 
> 
> ------------------------------------
> 
> Yahoo! Groups Links
> 
> 
> 

Thomas Heckmann
troperecordings - afu limited - afulab - trope mastering

Have one for sale

Sendt fra Iphone



Den 27/02/2012 kl. 20.55 skrev Thomas Heckmann <troperecordings@...>:

> Hi David,
> 
> I have two different 2002s and the boards and chips are not interchangeable.
> I tried to change them and it doesn't work.
> Even exchanged the complete board and this doesn't work as well...
> 
> Best
> 
> Thomas
> 
> On Feb 27, 2012, at 8:50 PM, dd_62622 wrote:
> 
> > Hallo,
> > 
> > I wonder if anybody is aware that there are two versions of cem chips that could be inside your p2000 ?
> > 
> > I have found out before and encountered the differcene again.
> > 
> > I have 1 p2002 rev A voiceboard with cem 3379 /8708
> > 
> > and another p2002 rev B voiceboard with cem 3379 /6833 
> > 
> > I wonder if these chips are interchangeable ?
> > any comment appriciated.
> > 
> > kind regards,
> > David
> > 
> > 
> > 
> > ------------------------------------
> > 
> > Yahoo! Groups Links
> > 
> > 
> > 
> 
> Thomas Heckmann
> troperecordings - afu limited - afulab - trope mastering
> 
>

the plot thickens .

just opened a keyboard version prophet 2000 (sampling keyboard;)

and to my surpise there was a mix of cem 3379 /8540     and 3379 /8542 installed.

I don't see any info on the net about the added nrs. on the cem 3379 chips.

I swapped the chips from the 2002 boards today and both units worked fine  .

cheers,
David


--- In prophet2000@yahoogroups.com, "dd_62622" <dd_626@...> wrote:

>
> Hallo,
> 
> I wonder if anybody is aware that there are two versions of cem chips that could be inside your p2000 ?
> 
> I have found out before and encountered the differcene again.
> 
> I have 1 p2002 rev A voiceboard with cem 3379 /8708
> 
> and another p2002 rev B voiceboard with cem 3379 /6833    
> 
> I wonder if these chips are interchangeable ?
> any comment appriciated.
> 
> kind regards,
> David
>

I have a bunch of 3379s from my 2000 that died. 

(before you all start in on me, I still have & use an expanded 2002 with sep outs & so forth; the key assigner failed in the 2000 & WC told me they were unobtainium, so I had to break her up.... I did not enjoy this.)

anyway, I plan to use the 3379s in a couple of other synth projects*, so I have read up on them a bit. there is ONE datasheet for the 3378 & 3379 variants of this chip, & NO mention of design changes or even different batches. if you have found them to be un-interchangeable, something else is likely wrong.

the 3379 has the VCAs set up with a stereo output pair & voltage controlled balance. the 3378 has an input mixer instead, & mono output.

duncan.

(*two at least as alternative filters- I'll leave the originals in- in my yamaha cs30. three or four more in a moog-based project. maybe convert my pro-1 to stereo.)

hallo Duncan,

I did read the infosheet as well.  no sign of any design changes or different versions as you mentioned.

still I have seen at least 3 different versions by now.

they are interchangeable and there seems to be a difference in volume and soundcolor as well.     still all of them are killerchips ; )

anybody with knowledge about these chips ?

cheers,
David

--- In prophet2000@yahoogroups.com, "duncan" <ferrograph@...> wrote:

>
> I have a bunch of 3379s from my 2000 that died. 
> 
> (before you all start in on me, I still have & use an expanded 2002 with sep outs & so forth; the key assigner failed in the 2000 & WC told me they were unobtainium, so I had to break her up.... I did not enjoy this.)
> 
> anyway, I plan to use the 3379s in a couple of other synth projects*, so I have read up on them a bit. there is ONE datasheet for the 3378 & 3379 variants of this chip, & NO mention of design changes or even different batches. if you have found them to be un-interchangeable, something else is likely wrong.
> 
> the 3379 has the VCAs set up with a stereo output pair & voltage controlled balance. the 3378 has an input mixer instead, & mono output.
> 
> duncan.
> 
> (*two at least as alternative filters- I'll leave the originals in- in my yamaha cs30. three or four more in a moog-based project. maybe convert my pro-1 to stereo.)
>

!! wow different versions of 3379's!

My 2002 looks like a rev C. (is that right?) 

there are 7x 3379/8609's and 1x 3379/8540 (!)

I'm thinking these might be akin to Lot numbers for production runs when these chips were manufatcured.

I have yet to open the 2000 to see. The 2000 has an 877 expansion board in it - is this suitable to facilitate the separate-outs?

Also has anyone had an issue where what seems to be a ground-loop hum that comes out all static'y and like digital noise? If I can post a wav somewhere like soundcloud I'll try to post a link so you all may listen after the weekend.


mixedmeteor


--- In prophet2000@yahoogroups.com, "dd_62622" <dd_626@...> wrote:

>
> the plot thickens .
> 
> just opened a keyboard version prophet 2000 (sampling keyboard;)
> 
> and to my surpise there was a mix of cem 3379 /8540     and 3379 /8542 installed.
> 
> I don't see any info on the net about the added nrs. on the cem 3379 chips.
> 
> I swapped the chips from the 2002 boards today and both units worked fine  .
> 
> cheers,
> David
> 
> 
> --- In prophet2000@yahoogroups.com, "dd_62622" <dd_626@> wrote:
> >
> > Hallo,
> > 
> > I wonder if anybody is aware that there are two versions of cem chips that could be inside your p2000 ?
> > 
> > I have found out before and encountered the differcene again.
> > 
> > I have 1 p2002 rev A voiceboard with cem 3379 /8708
> > 
> > and another p2002 rev B voiceboard with cem 3379 /6833    
> > 
> > I wonder if these chips are interchangeable ?
> > any comment appriciated.
> > 
> > kind regards,
> > David
> >
>

>>they are interchangeable and there seems to be a difference in volume and soundcolor as well.     still all of them are killerchips ; )<<

they most certainly are! :-)

duncan.