[sdiy] CEM chip CEM3391

[dj hohum]

Hi Paul,

That's about what I expected. I'd rather use the korg chip or the
3372. In either case I'd like to get them as cheaply as possible :)
For those suggesting that I "design"  a circuit around OTAs etc etc,
part of the appeal of using the CEM chips is that there isn't much
"design" to do.

> > but I wouldn't recommend using the CEM or the SSM chips for new designs as
> > this means there are less available for repairs.
> > regards Peter
>
> Well, I have a *lot* of CEM3391s, and the only *repair* that I've ever seen is
> that
> it was used in 1 obscure Hohner synth.
>
> So, don't feel bad about 'stealing' these away: PLEASE buy some!

They look fun, but the VCF output is hardwired to the ADSR controlled
VCA. That's not what I need right now. If they were cheaper I'd
probably buy a handful. Maybe you should run a special on them since
they aren't that useful for repair.

> And I have over 1000 CEM3340s left, too. Don't worry about them, either :)

Personally, I'm not worried at all about them. I have a handful of
3340s recovered from two synths that I plan to use in my own projects.
I don't think it would make business sense to design a new product
around them, and it probably doesn't make sense to build something you
plan on keeping forever around them either. But, it's simply an
economic tradeoff whether one wants to build something around an
expensive chip or build a more  complicated circuit instead.

The CEM/SSM chips are fun to build diy stuff around because they are
so easy to use.

What will happen when they are depleted, presuming that onchip isn't
convinced to do another run, is that people will either raid them from
other synths or someone will design a replacement built from SMT parts
on a chip carrier. This has already happened, for example, with the
Roland VCF/VCA chip. Granted, the Roland chip is a bit larger.

At any rate, it's just another project on the list and I think it will
get finished right about the time I stumble across a DW8000/6000 for
cheap.