I have a lot of details about the different Russian green versions on this page.
http://www.kitrae.net/music/big_muff_history2.html

The Red Army Overdrive, Civil War, Green, and Black Russian Muffs all sound in the same family, but there is a very noticeable difference in sound from the green to the current black, to me anyway.

I have two of the tall font green Muffs and they are a bit smoother sounding and have a bit less gain than the later bubble-font green Muffs. The bubble font version seems to have more balls to me. A bit boomier and the mids sound better. I have had six of those over the years. The later large box black Muffs sounded the same.

The current small box Russian Muffs are less big sounding/boomy than the greens, and the mids don’t sound as good to me. Lots of people don’t like the boominess of the greens so that is probably why they sound different now. You would have to play them side by side to hear the difference, but there is a difference. As Liberty Belle said above, the sound of the green Muffs vary from unit to unit. Three of the six I had sounded virtually identical, and I had one with considerably less gain that the rest, and one with crappy sounding flat mids. It’s all in the different components used from unit to unit.

What people need to remember is that EVERY big muff varies, no matter what issue it is.
EHX/SOVTEK didn’t change parts and values just cause they changed a font!

I have schematics traced from tons of alleged variations of the same version big muffs and they are all the same values used.

Buy any two 1981 3034 big muffs or any two 2005 3003-A big muffs, they will sound different. do the same with any two identical green sovteks, they will sound different.

FYI, they will always sound like a big muff but there’s always slight differences.

BTW, I’ve modded Black sovteks into green soveks and couldnt tell the difference, they sounded the same as before the mod, and you shouldn’t be able to either considering its only two resistors that have a sightly different value.

So remember, its very unusual to find any two muffs of the same model to sound the same let alone different models!

What it generally comes down to is: TOLERANCES will effect the sound a lot. And to a smaller degree TYPE of parts will effect it too. And from experience and observation vintage EHX and Sovtek tolerances were all over the place,drastically!

An example of majpr tolerance difference is the pots in my 1966 mustang, they are supposed to be 250k audio pots and indeed they do say they are CTS 250k audio pots but the volume pot is 320k and the tone pot 290k, thats a difference of 70k and 40k and in a guitar that not a great deal but in a big muff tolerances that vary that much will drastically change the sound of any muff. I’m not saying big muffs tolerances vary this much, in fact i highly doubt it but they dont need to vary this much to change the sound in this pedal either. even 5-10k either way will change things. And I havent even mention capacitors and transistors yet!

I have a muff,I think its my 3034 big muff, that should have 3x100k pots, yet one is 90k one is 100k and one is 125k, them tolerances aren’t tight!

Yeah,initially when I first started collecting muffs I had a RI NYC 3003A version and it sounded different to the one (exact same version) I have now.

I still want to get the 3003B (not too many around me thinks as it was a 2007 revision then the B come out in 2008) and the 3003C, which is the latest issue.

The BMPTW sounds cool though, one of the best they have made in years!

They have always had that pic (them knobs), they haven’t updated it since they re-issued it i think.

For as long as I can remember, at least 4 years since I started visiting the old EHX website, this has been the photo EHX has had up IIRC.

I could be wrong but I really don’t know for sure.