[sdiy] Yamaha CS-60 issues

[Michael E Caloroso]

Not planned obsolescence?

When's the last time anyone has contacted Yamaha for data sheets on
the custom ICs, with the hope to replicate them using modern
technology?

They don't have them.  They're gone.

Why?  Back in the 1990s, Yamaha destroyed their spare stock of custom
ICs and their data sheets. They could had auctioned them off, could
have digitally scanned the data sheets for perpetuity.

But no, they DESTROYED them.  Gone forever.

I respect intellectual property, but as a consumer this disposition
makes me very reluctant to buy Yamaha products with the very real
concern that they will have a short life and spare parts will not be
available for repair.

Yes I am well aware that custom parts are all over in modern devices
and that warehousing spare parts is expensive.  But destroying crucial
info on the technology of the custom parts crosses the line.

PMI destroyed crucial info on the SSM parts.  The much-loved SSM2040
was hailed as the best sounding VCF-on-a-chip.  Are they gone forever?
 Not while the original designer - Dave Rossum - is still around, and
he was part of the design group for the new SSI2140 VCF.

There is a big demand to keep old gear running.  Rossum shares this
passion.  Yamaha doesn't.  Sure, Yamaha has been teasing about a CS-80
reissue... for YEARS.  Maybe their disposal of crucial tech info on
those custom parts is hindering their efforts?

Still dispute the planned obsolescence label?

Open up an early Yamaha analog synth and inspect the electrolytic
bypass caps.  The original caps on the 15 volt rails were rated at >16
volts<.  Anyone who has been in EE classes knows that the decades old
design convention is to spec maximum voltage ratings at DOUBLE the
supply rail.

Any design that underspecs the components is destined to fail.  This
doesn't fall under intellectual property.  This is planned
obsolescence and it was intentional.  When I see that kind of poor
quality in a product, I refuse to patronize that company.

Yamaha is hardly alone... I see inferior designs from many countries,
including the US.

MC

On 10/6/20, Gordonjcp <gordonjcp at gjcp.net> wrote:
> On Tue, Oct 06, 2020 at 07:33:17PM +1000, Adam Inglis (sdiy) wrote:
>>
>> Interesting points Mattias!
>>
>> What exactly did these chips do that could not otherwise be done?
>
> Cram a bunch of functionality into a single chip, instead of a
> postcard-sized piece of PCB.
>
> Compare the PCB of the Sinclair ZX80 from around the same time:
>
> https://www.8bity.cz/wp-content/uploads/2011/05/ZX80R_najdi_10_rozdilu_thumb.jpg
>
> with the PCB from the ZX81 where all the "glue logic" was crammed into a
> single Ferranti ULA:
>
> https://upload.wikimedia.org/wikipedia/commons/thumb/b/b7/Sinclair_ZX81_PCB_Top.JPG/800px-Sinclair_ZX81_PCB_Top.JPG
>
> You'll probably find that Yamaha's "custom" chip was similar to the
> off-the-shelf ULA used in the ZX81.  All the gates and stuff are there, they
> just need a couple more layers of metal to wire them up for the user
> application.
>
> --
> Gordonjcp
>
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