New Moog schematics

Is there anybody has a schematic of Little Phatty or Voyager?
At least, if anybody has photos of these synths naked? :wink:
I’m curious what electronic parts were used for VCO, VCF, DAC+S&H, etc…

I’ve looked inside some of these… Nothing fancy, transistors, LM13700, TL07x. DACs were too small to read :slight_smile:

There’s some photos here of a Voyager stripping.

The VCF uses a CA3046/3086 for the matched top and bottom transistor pair. Dunno about the VCO or DAC/S&H, but the CPU is a z80 derivative for that ancient and moldy feeling.

The voyager has lots of 13700’s TL074’s, CA3046’s, some LM837

EDIT, beaten to the punch. Nothing fancy.

They still cook with water - no magic thingies !

oh, and here’s some hi-res photos of the Little Phatty. SMT just doesn’t look nowhere near as sexalicious. And a hi-res photo of the inside of my Voyager OS.

Thanks guys!
Nothing fancy, indeed. Only LM837 seems to be kind of “high-end” part in comparison to TL074.

@MaxZorin: You might want to have a need of this most interesting page entitled Op Amps: Myths & Facts

Martin

Thanks Martin for link!
I didn’t use the word “high-end” in the sense of an audiophile. LM837 seems to be “better on paper” and it’s only slightly more expensive. It would be interesting to know why they used that instead of the TL074.

I read a great post a few years ago about the NE5532, the argument was that they were only cheap due to mass production and they were as good as most of the newer op-amps that are out now that cost 10 times as much. Its a good argument as I suppose the chips all cost as much to make as each other as there is just a square of silicon with some legs, if you make a really good design and then make millions of them after 30 years they end up cheap.

+1 for the NE5532. Unless you want to add the LME497x0 which sound great on the Ambika mixed output btw) but then they cost a bit more.

I see the point of NE5532s in mixers, preamps, EQs etc where your job is to be as transparent as you can with the signals the user of your product has entrusted you with.

I don’t see the point in an analog synth where the coloration added by op-amp noise/distortion is negligible compared to all the trash coming from OTAs or VCAs.

These days, the whole point of a hardware synth seems to be to color in a way virtual analog still doesn’t seem to manage.

years ago I made a simple RIAA pre amp for my record player and tried swapping the op amps around, of the ones I tried the only one that was noticeably bad was a 741, I left 5532s in in the end after trying a few. The 741s are industrial op amps though so it’s not surprising they didn’t sound good. The argument that people want colouration is an interesting one though.

Getting back on topic, those through hole component Voyagers look very cool!

@Dunk
If an OpAmp “sounds” bad its the whole circuit that isnt fitted to the OpAmp, not the OpAmp itself. You cant break down a whole design to just one single part and you just cant swap a part in a well thought out whole.

Just because a rivet is a bad Idea to build a ship that occasionally might hit an Iceberg or a floating Container it doesnt mean rivets are bad - think about this when you next time sit in a Plane.

I’m sure there are still “battle-tested” circuits in airplanes using NE555 and 741s :slight_smile:

Actually id rather sit in a Plane that is bolted together with a zillion rivets and relies on 555s and 74Xs rather than in one glued together from carbonfibre epoxy and has LiFe Batteries to power their Win8 computers running on a i7. . . .

Oh come on… What could POSSIBLY go wrong?

Nothing besides the LiFe battery failing, burning, instantly melting thru the plastic body of the plane thus inducing a pressure drop and structural failure, the win computer not noticing because of a wrong registration key of some vanilla stock .DLL . . . .
“The Module ‘Plane Crash Countermeasures’ is not certified by Microsoft! Abort/Cancel/Hangup”