The Official Marshall Studio Vintage Thread Sv20h

[AbstractSnow]

Oh yeah, forgot to mention: normal channel mixing resistor got a 470p across it now, and on the pictures you can see my bright cap dial as well.

I hope I didn't forget to solder any gaps. Haven't put it back together yet as I gotta run some errands now. Hope you guys enjoy!

Edit: back home and tested, works! It's more tame now thanwith what I had before. Certainly less fuzzy. Much more 2203. I think a little more noisy as well (correction: I had some ground loop stuff going on). I may have used a bit too much unshielded wire. Kinda ran out.. :')
So if anyone wants a less tame 2203, just do what I did before

Now that the normal channel has the cathode switch, I miss the pumping compression I was able to get when I had that on the always bypassed bright channel. If I had to guess, the bypass + very high cathode resistor caused some of it. Or maybe the 20k isnt enough to cause it yet. We'll see.

Oh yeah! This PPIMV gets a noticable bit cleaner at lower settings. So the cancellation really was not perfect. When it's just slightly under 10, the EL34s immediately stop being squirrelly. I like that. Sounds a bit more modern that way. (Edit: check the next post, I made a big oopsie here. No wonder it was being "squirrelly" at max..)
If you want the exact same tone at lower volumes, but don't mind the absolute lowest settings being harsh, do the crossover one (but definitely add a way to reduce the NFB resistor, you will need it). I wouldn't say that the added complexity of the dual gang pot is worth the better behaviour at very low settings imo.

 

[AbstractSnow]

After having messed around with this version of it, I like it, but I was wrong in thinking the big coupling cap wouldn't hurt, back to stock that one. As a "fat" switch that could work well, but not a huge fan of leaving that value in permanently. I like being able to move my bass control away from 0.. and if I do need more balls, the depth control got me covered. Very nice that one.

I'm not sure the dual pot MV does what I want it to since it cleans up too much for the volumes I've been trying it with. So despite it having a much nicer taper, so to say, and since it's a bit much dangling inside the amp, I'll try to find a way to make the crossover one work better instead - cleaner, simpler, just gotta get rid of the fussiness at very low volumes..
Diodes haven't arrived yet, probably later this week.

(EDIT: Looked inside - here's proof of me being an inexperienced idiot: I forgot to attach a ground to the MV. Essentially it was acting like a crossover MV with a really large grid stopper and no grounding, or like no grid stopper and no grounding before the EL34s. Well. Using 4 cables going back and forth was totally unnecessary as well, another brain fart on my end. Now I turned it into both MVs, because switch, and why not? 3 master volumes... Yup.. choose your flavor galore)

V2 bypass cap is back in, and that's very much better than without. Don't snip that one A switch with a bigger one sounds fun, the Friedman Plex has a 22u there instead of the 680n so I'll try that one as a switched option.