Aetherwellen Simple Etherwave Bass Mod

Thanks for the detailed response, Dewster! I checked out the recordings you linked—very helpful to hear the before-and-after of both the Aetherwellen mod and the YAEWSBM v2. It’s interesting how these mods impact the tone, especially with that "meowing" effect you mentioned. I agree that this might come down to personal taste, but I can see why some might prefer the raw, stock sound.

For me, the idea of improving linearity is tempting, especially since my current pitch field feels a bit inconsistent in the far range. I’d probably prioritize that over any tonal changes, even if it meant losing some of the original bass timbre. You’re right, though—having a reversible option like the Aetherwellen mod makes it less of a commitment compared to the semi-permanent changes with the ESPE01 or YAEWSBM.

Out of curiosity, do you think there’s a "sweet spot" for balancing linearity improvements without overly compromising the timbre? Or is it pretty much a trade-off no matter what?

Thanks again for the insights and for sharing your thoughts on these mods!

Oh and TIL you developed the D-Lev synth that I hear about so often! Wowzers 

"Out of curiosity, do you think there’s a "sweet spot" for balancing linearity improvements without overly compromising the timbre? Or is it pretty much a trade-off no matter what?"  - jsherm

Not being an analog Theremin designer, I haven't studied the pitch oscillator coupling tradeoff of far field linearity vs. low end timbre.  Some Theremins allow you to adjust the strength of the coupling, the ones I'm aware of are: Etherwave Pro, tVox tour, Hobbs, and the new but now gone Etherwave.  Long ago IIRC I read that the tVox somehow employed coupling to help linearize the pitch field?

I listened to all the sounds you linked a few times. I do hear the smoothness of the mods, but that's about the only difference I hear.

Maybe one day in the future, after I feel comfortable enough using my EW (I'm progressing nicely each day), you might feel inclined to possibly install the Aetherwellen mod for me in person 

"Maybe one day in the future, after I feel comfortable enough using my EW (I'm progressing nicely each day), you might feel inclined to possibly install the Aetherwellen mod for me in person "  - jsherm

Sure!  You're maybe only 70 or so miles from Boonton?  If you visit you could try out the D-Lev some too.

Yeah, it looks like I'm an hour and 20 minutes away from you. I could definitely take a trip out there one day!

I'm starting to finally get comfortable using the EW. Yesterday I was able to finally play a scale in two different octaves pretty easily. And today I was able to do the same and also play a song or two.

I think I finally got past the main challenge which was tuning the pitch to fit my hand. Now that I have figured out how to do that, thanks to all the suggestions and tips from everyone, I have to get more in tune and precise.

Do you have the Aetherwellen mod? If not where would I buy one? Have you installed one in an EW standard before?

And trying out the D-Lev sounds like fun!

"Do you have the Aetherwellen mod?'  - jsherm

Yes, I have the capacitor and resistor.

"Have you installed one in an EW standard before?"

No, just the Etherwave plus, but depending on the vintage the base PCB is probably the same.

At least for circa 2017/2018 there is no difference at all in the EW main pcb for the standard and Plus.  I bought several of the EW main boards and a couple of the CV boards back when Moog was still friendly and the parts were cheap. The Plus is simply a standard main board with the CV board added, plus the requisite extra cables, different panel, and of course the case mods for the extra jacks.  This is confirmed as the spare boards match those found inside my EW Plus from that period.

There was also a retrofit kit available from Moog including the CV board panel and the associated hardware to turn a standard EW into a Plus.  I would venture that there is no difference in performance or sound between the two models that would rise above minor individual variations.

"At least for circa 2017/2018 there is no difference at all in the EW main pcb for the standard and Plus...  There was also a retrofit kit available from Moog including the CV board panel and the associated hardware to turn a standard EW into a Plus."  - pitts8rh

Yes, that's my understanding too.  Having poked around in various EWs, the earlier ones like Big Briar had somewhat fragile PWBs with 4x10mH pitch coils and 2x2.5mH + 2x5mH volume coils, and used LM13600.  Later EWs used a more robust and differently laid out PWB with 3x10mH pitch coils and 2x2.5mH + 1x5mH volume coils, and used LM13700.  Not sure how closely these changes tracked each other, nor how the coil changes may have affected playing.  Roger, I believe at one point you posted an updated annotated EW schematic?

"Roger, I believe at one point you posted an updated annotated EW schematic?"

Yes.  This is for the 11-211J pcb.   Values that were different from the original schematic that I started with are in red.  Note the oddball cap C22 on on side of the power supply that is a larger tantalum.  It's real, but I don't know why - maybe 78xx/79xx regulator differences? 

I can send you a pdf if you want.