Great to see what you came up with.
I’m doing some research on my side as well and find a lot of cool stuff from that time.
more hints:
A japanese company that was marketed under several names, all vanished into oblivion.
This was their flagship model. It has a “polyphonic” (divide down) string section with after-touch, presets, ensemble and “leslie” effect.
Plus a (split keyboard) monophonic bass and a monophonic lead synth.
Ace-Tone [ early Roland ] ?
Again, I don’t think it’s it because it’s too “new,” but the Teisco SX-240 looks super rad.
Univox / early Korg?
-Fumu / Esopus
“vox” is in it’s name, not uni but …
Trapa Natans,
Multivox was from the United States and licensed devices from Japanese builders. I’m aware of one that they worked with called Firstman and that much of the designs were said to resemble Roland but never came from them. I had some imagined thought they did a drum machine but their only similar products were two sequencers (a bassline sequencer and one for keyboard.)
-Fumu / Esopus
OK, Japanese company was misleading then. It says Made in Japan though.
It’s supposed to be identical to the Pulser M85 but that looks a lot different.
Trapa Natans,
Well you aren’t the only one, as some information about Multivox I’ve found is poor. They did make a drum machine but curiously its common Roland / Ace Tone namesake FR-6 bares no resemblance besides name. The other thing I learned more details about the builders from Japan. Hillwood was the builder for Multivox which was started by Kazuo Morioka and also had for a time worked for Firstman (his name means First Man Wood Hill.) Hillwood had made synths which were renamed for synthesizer companies like Pulsar. Any resemblance to Pulsar M85 may not be coincidental.
-Fumu / Esopus
It sounds fantastic! I hope you can get yours working
Bass and string section are working as well as the effects, filter doesn’t and the solo synth has no sound, but ADSR and the rest seem to work. It’s hard without schematic, especially with the stuff on the frontpanel PCB. The small modules are service friendly but I hate these white molex connectors. We have them in our companies products and they cause issues after some years.
But it sounds great already. I found this in a forum.
Oh this thing is rad. Very rad.
Damn I always took those parts for a CS-80. Super pretty sounds!
Deoxit is by far the best. I haven’t used the concentrated stuff yet, only D5 spray for old pots and switches. It’s well worth the money.
Hooray, I finally found and downloaded the service manual including schematics today.
So here is the block diagram. This helps already, I will have a look at the “key down detector” first. All that is not working seems to depend on that.
This seems to be the VCO of the (unfortunately not-working) Channel 3 lead synth part. I redrew it because the values can’t be read on the original pdf. It looks a lot like the Thomas Henry 555 VCO and fairly simple. I wonder what the upper right part is doing.
