Yep, trying to keep as true to being in 1980 as I can.
And since my R&D is funded by Commodore (I mean Admiral), I am using parts they would have at the time like the 6502, 8050 drive and VIC/PET keyboard.
So far every one of the 1000+ ICs is either basic SRAM, a 6502 or standard logic gates.

Even my CRT is almost the same as what was in the PET.
It is from an early CNC machine (I could not bring myself to gut any of my working PET systems for parts).
Luckily I found it new in the box on ebay... super rare find and even has 2 brand new 12" mono tubes.

I am using HC logic instead of TTL, but the tech is identical.
Did that since all the logic I am using is actually still in production, and in DIP format.
Also because I do not own a power generation plant, and 1200 TTL ICs would require one hell of a power supply!

Well, you _can_ use the steam engine for something more than moving the thing around then!

Neil

Steam is a bit too retro for my 1980's target!
Besides, how would I ever compete with this one?...

https://www.youtube.com/watch?v=Z7FsZD7JX0I

Dark metal panels, rich redish wood, loads of analog flavor on top of a digital base and a boatload of 1980's ICs.... that's my gig.

I suppose that's an improvement on this horror: https://en.wikipedia.org/wiki/Stylophone

_________________
x86?  We ain't got no x86.  We don't NEED no stinking x86!

My direct competition is the Fairlight CMI Series 2.
https://reverb.com/ca/item/53824979-fairlight-cmi-series-iii-fully-restored-owned-by-brad-fiedel-terminator-ii

Improvements in my design will be...

- Up to 64Khz sample rate over their 32Khz
- 400K sample memory per channel over their 64K
- Multiple analog filters section per channel. Theirs has none.
- 12 native sample channels, each with 8 poly voice. They have one voice.
- Built in 200 watt amp with stereo reverb. They have none.
- Voice synthesizer track and master FX. Also not included with Fairlight.

As for being cost effective in 1980, Admiral Business Computers (my partner) has vertical integration so I don't have to tool up to to plastic injection on the keyboard (alpha or piano).
We also have a disk drive unit and CRT, both from the ABM-4016 production line. Oh, and those 6502 CPUs... also made in house.

Because of this vertical integration and Jacques Leimart's shrewd forward looking acumen, we are able to hammer out 8 times the sample RAM per channel, which is where the true power in such an instrument lives.
The Fairlight sold for $40k in 1980. This Synth may be 1/4 of that, putting it in the hands of mid sized musicians and production studios.

Brad

I played around with the color scheme a bit on the model and like where it went.
The look should scream out... stuck in the 70's but trying out the 80's.



Cleaned up the detail on the working keyboard as well.



Only the knobs and switches are undefined at this point.
The two large ones beside the piano keyboard are probably a go.
These are expression encoders that can be assigned to just about anything from pitch bend to low pass resonance.
I don't like the typical pitch wheels on keyboards, so I am going rotary with mine.

Going to try cutting the working keyboard cutout tomorrow if it isn't too cold outside.
So close to moving everything indoors for the year so I can dig into the circuitry.

The way electronic music is created is going to change forever in 1980 when this powerhouse is released!

Radical Brad

Fashionable knobs of the era were proper collet knobs - the three-part type with a screw under the cap to tighten the collet on the shaft, none of these modern rubbish push-on types! (Also available marked up to 11 )

As an aside, I recall knocking up one of these - probably from the Maplins kit - in around 1978: https://www.trevormarshall.com/eti.htm

It's from the days when men were men and not only expected to know which end of the soldering iron was hot, but how the circuits worked, too! ETI was one of the better hobby magazines.

Neil

Nice vintage unit! The first video really shows off the sound. It's multi track and processed through echo, but still a great demo.
I also like the matrix pad, much better idea than patch cables.

My first synth was a 1979 Moog without patch cables. It was limited but fun.

I also have to deal with some channel switching in this design later.
Standard sample channels (12) will be split into three, each running to several dedicated FX... low pass, resonance, distortion and possible digital delay.
I may just cram a load of pots on the front panel and do this all in analog mixing, but not sure yet. CD4066 analog switches are also an option.
The remaining 4 channels are specialized, one for the Votrax style speech box, one for a theremin type live play instrument and last two yet to be determined.

Looks warm out today, might get a chance to hack out the working keyboard cutout on the main plate.

Brad

The rain held off this afternoon, so I attacked the front plate with my ultra high precision cutter.



I used the paper template to trace the cut line, and kept a bit inside the line.
Always better to take too little than too much material away on the first cut.
Another space-age precision tool was used to clean up the grinder cuts.



After 2 hours of good arm workout, I had something that fit nicely.



Will need a few small lengths of flat bar to make a keyboard mount, but that will be easy.
It looks like a lot of empty space back here, but the speaker boxes are going to take up much of that room.
There will be enough room for a power supply, the 200 watt audio amp and a few extras like the spring reverb unit.



Another small part completed thanks to a mild snow free El-Nino winter up here in the North.



Next I will make the keyboard attachment points and might even have time to do the speaker plate borders.

Brad

_________________
x86?  We ain't got no x86.  We don't NEED no stinking x86!

I own the following high precision tools...

Bosch angle grinder from 2009.
Bosch corded hand drill probably 20 years old.
Miller AC stick welder from 1990.
Hammer, adjustable wrench, screwdriver, bigger hammer.
I work mainly outside as my shop as an old construction trailer full of leaks.

I kid you not when I say this is how I choose to do things. Self inflicted insanity!
Never plan to change, it's way too rewarding to achieve what I do with so little.

_________________
x86?  We ain't got no x86.  We don't NEED no stinking x86!

Well that puts my hardware engineering this week into perspective: I wrapped some insulating tape around my toothbrush to stop the removable head removing itself at random times...

Neil

_________________
x86?  We ain't got no x86.  We don't NEED no stinking x86!