Vintage Simmons Drums (UK) Users Group

Hi Michael,

"Backplane" is the correct term. Computers and associated devices often have a
back plane, with slots that daughter boards slot into. For example, a PDP-11 is
little more than a case with a power supply and a back plane into which boards
containing the processor, memory disk controllers, etc. would be plugged. I
assume Simmons took the terminology from there.

Chris

On 13 June 2013 at 13:43 Michael Buchner <buchnerelectronics@...> wrote:
> As Pratrice says right: SDS7 often brings you somewhere in between frustration
> and fascination.
>
> 1984 I was touring when we had a narrow stage so I could place the brain only
> on the side because of no space. When checking the sound, I realised that all
> parameters in every program of the whole unit were on 255. All settings were
> gone, no memory cartridge.
> The basic idea of SDS7 was brilliant, to combine sampled sound with synthesis.
> But the construction was a mess. Starting with the frame: Channel in/out
> numbers were in the false direction beeing not behind the corresponding card
> on the front. Summing rails near the data lines with all the noise bleeding
> in. They made a noise reduction later with an unused opamp on the back panel,
> funny, because of a writing error this was called "backplane" instead of
> "panel" from then.
> The steel case was not stable and bent all the time. So the card placement was
> always not sure and the contacts with the back"plane" horrible. Some
> improvements were made, but without any positive result. The servicemen called
> it "Simmons cabasa" because of all the parts falling around inside the case.
> To have more contact for the CPU, they bent the CPU PCB to the side and
> attached it like this! Raw and brutal! They tried to "hot glue" the parts.
> They called back all sold units to improve them several times. They were in
> despair!
> And it was very expensive those days. Until today I don't understand, that
> they had gold-plated fingers and an expensive (useless) XLR "graveyard" on the
> back and- took the cheapest push buttons for the programming panel.
> I once sent a 7 to the U.K. when a message came: Not working. I had to pay all
> the shipping to and back. At home again, I checked it again and made the "SDS7
> standard repair": CPU and RAM out and in 10 times. And: Working again until
> now.
> I love and hate my 7's...
>