The Amp Garage

Don't misunderstand me. I REALLY appreciate your opinions! :D Maybe I first tried the amp under the wrong circumstances (high output pickups, heavy strings and hard playing)! The first thing I probably will do is to go back to B+ voltages that is more Dumble or Dogears like. When Johan then is playi...

Please excuse that I repeat myself AGAIN! The distortion that in my ears where ugly, that this thread from the beginning is all about, occurred in the FIRST gain stage, BEFORE the preamp Volume control. The settings on the preamp volume had no affect at all on THAT distortion. It seams that many of ...

Johan, I hope you will get answers from more people, but as I think I've already told you, my impression before I tweaked the clean "channel" to be "absolutelly" clean, was that the sound of it, when ovedriven , was more Robben Ford like than the Ovedrive channel. At least if you think "Handfull of ...

I have heard of lots of failures with those small PR series from a couple major builders. I also think they are more like a metal oxide. They are really small!! If they are metal film (I know they are advertised as film) , they are totally different than what we know as metal film. I would stick wi...

Thanks for the answers. OK it's precision metal film resistors. I live in Sweden... Maybe my best local vendor is to buy where you buy... My main question, though, is still: What do they do for the sound? What's the difference in sound with these or with, for example , more conventional 2W metal fil...

Hi, I wonder about the light brown "milk chocolate colour" plate resistors that many people use in their Dumble inspired amps and as it seems HAD himself used. See picture: What kind of resistors are they? And most important, what do they do for the sound. What’s the difference in sound with these o...

This one was my suggestion. ;) :lol: :lol: Yes, I'm also mostly a big believer in low serial resistances. That's the main reason I posted the suggestions for a, what I think is good mod for Fender AB763 reverb channels to have only 180k instead of 3.3M as serial resistance. I did that this summer b...

Sorry for being a dumb ass but which 150K is this resistor? Are we talking about the plate resistors or grid resistors? And on which side? V2a or V2b? I'd like to clean up/ make it tighter, the lower end on my D44 a little. Look at this schematic: http://ampgarage.com/forum/download/file.php?id=117...

...I have been endlessly soldering and experimenting for years now and there are several things that are pretty certain. One is plate voltages and OD tone... In the amps you've done that. What main B+ voltage has the power transformers in them given under load in the amp? Please answer! I'm really ...

Oh... Try lowering the choke replacement to 300ohm, 330ohm, or 390ohm. Whatever you have on hand. Maybe try a 1K across your 500ohm. I bet you like it more! :D You bet! I have already tried that and personally I like it better with 330 ohm :wink:. But, I like to have it as it is untill Johan himsel...

Of course I couldn’t resist trying lower plate voltages on V2 as per dogears’ suggestions... :wink: ... Yes, I know I said I should send it to Johan as it was, but if it could be better before I did that, I wanted to do it... First I like to make clear, and repeat, that the ugly distortion that this...

dogears, Thanks a lot. I think I see your point, but I think(!) I will do more changes only after Johan has tried his amp for himself. Personally I think the overdrive sound is rather good now, but I really want to know what Johan thinks. What "sweet OD" is, I guess is rather personal? As you can se...

OK. Now I've done some things and am satisfied for now :D . I've done most of dogears' suggestions except the ones in the power supply. I've also changed the first tube to a NOS GE 5751. I also tried different values on the FET simulator resistor and also tried without this resistor. The problematic...

Just to be clear about the distortion, are you talking about the bass notes farting out when you really dig in to low notes? (Almost sounds like a bad speaker.) If so, I've experienced this with nearly every Dumble style amp I've ever built. With only 1M/22k loading the grid of V1a, it's probably t...

If you think it distorts with "normal" attack something must be wrong. Hope it's not too much of a trouble for you. Sorry the build took longer than expected. Don't worry. I will fix this. But maybe you will not get the amp before next saturday. And please don't be sorry! I like this work very much...