The Amp Garage

Cool. Can you compare the sound of your current lift compared to the previous one, and where did you set the trimmers? :D Yes sir. I'm not sure if you mean previous as in D'lite with dual controls, or BM with the type of PAB I had yesterday (pre mod) with bass ground tied to top of the mid pot, and...

Yea, so you just lifted the ground of the mid pot, is all. That's fine, and a common way to do it. But i think this is what you were trying to do ? One way is normal, and the other variably lifts both bass and mid. I'm curious how this one sounds with a Marshall stack. Yay, it worked. I didn't even...

Yea, so you just lifted the ground of the mid pot, is all. That's fine, and a common way to do it. But i think this is what you were trying to do ? One way is normal, and the other variably lifts both bass and mid. I'm curious how this one sounds with a Marshall stack. Cool. That is pretty much wha...

Got all changes complete. So everything except OD stage has Bluesmaster config. Everything sounds amazing, except PAB. It is way too bassy. I really liked how the previous tonestack / PAB config, allowed independent control of the amount of lift applied to both bass and mids. Now that I have the ot...

Yes, If you look at the evolution of the 5F6A presence from Fender to Marshall, you'll see that ultimately Marshall ended up going with a 25K pot with a 4K7 strapped across it, which gives you a tail of ~4K. Close enough. Someone please correct me if I'm wrong here, but the 25K pot helps keep the c...

Got all changes complete. So everything except OD stage has Bluesmaster config. Everything sounds amazing, except PAB. It is way too bassy. I really liked how the previous tonestack / PAB config, allowed independent control of the amount of lift applied to both bass and mids. Now that I have the oth...

Nice! I would encourage you to draw a schematic of your tonestack, as-is, then compare it to the BM ts. You can keep your PAB and convert the rest over by moving 1 wire. It's the NC one(to ground) on the Bass pot side of the switch. Instead of going to ground, you put it at the top of the mid pot. ...

Sorry to bother you again. But, I have been reading a ton of presence control stuff, and I'm seeing people get steered away from 25K pots towards smaller (5K) pots. Also reading that the presence pot should be about 5 times the tail resistor. In this case, the Bluesmaster is 4k75 tail, so I would th...

That is correct. You can look at the ratios : D'L 390r : 4K7 = ~12 BM 4K7 : 100K = ~21 So the BM will have less NFB, resulting in a dirtier/wilder amp, so to speak. If you need to tighten up the bottom end or if it's too wild for your liking, drop the 100K down to 56K and you'll have about the same...

Nice! I would encourage you to draw a schematic of your tonestack, as-is, then compare it to the BM ts. You can keep your PAB and convert the rest over by moving 1 wire. It's the NC one(to ground) on the Bass pot side of the switch. Instead of going to ground, you put it at the top of the mid pot. ...

Well, even though I don't think it's fully done yet, I got to listen of my little Blue Frankenmaster Delight. Lol. Several things have improved a lot. Earlier breakup of clean channel is just right. Love it. I also think the lower value caps used for the BM make it less tubby, and more focused. I on...

I think you're obsessing over that 110K a lil much :) While it does matter, the 110K while be able to give you a very good sense of things, for now. It's not like you have to decide now, like forever. Just clip stuff in, or do what I usually do...just fly components all over the place, soldering to...

Ok, that's what I was getting at... Look at it this way. This amp, as a whole, is an entire system. If you study the other amps, you'll see similar topology, but different systems. If you break them down a bit, you have the clean section, and the OD section. They all have these 2 sections, but ther...

Close enough for now, yes. 470K? Are you changing the OD 1 and 2 (V2a/b) as well, and adding the extra tonestack at the end? Full conversion? Hi Smokebreak - I wasn't planning on second tone stack. I have been trying to work though the schematic that you provided, and determine what component chang...

I just bit the bullet, and rotated the 12AX7's 180 degrees on the D'lite to Bluesmaster conversion. A little bit of PIA, but nowhere near as frustrating as finding out I forgot to order 121K or 120K resistors. Didn't even have the right values to parallel in. I just stuck a 110K on the plate of the ...