The Amp Garage

I've heard good things about the new tung sols, I'll have to try them out some time

Thanks for the hi-5 my friend.

It's been a bit but I thought it'd be nice to post an update. It took me a while to order some replacement pre-amp tubes, get my scope back from a friend, order a dummy load etc etc. After taking apart the chassis and taking some time to get familiar with it (the amp's a bit overwhelming when you fi...

All the really expensive stuff seems to be working fine. Yeah this is a big relief, thinking about spending, $300 or so on power tubes and filter caps just to see, well I wasn't looking forward to that. I love SVT but only with 8x10 because that takes the clouds out of the lowend. Modern expectatio...

Ok, spent some time at the practice space after work checking out the amp. So first things first, the original schematics were still in the cabinet! They're dated 1975. So that's cool. http://www.el34world.com/charts/Schematics/files/ampeg/Ampeg_SVT_PreAmp_.pdf http://www.el34world.com/charts/Schema...

I feel like I've been circling these things for the past 20 years and last week I finally picked one up. I played it a bit by myself, seemed cool, but today when I got to use it at practice it was kind of blah. My 250w Galien Krueger 400b really put it to shame. Seems unthinkable, right? Before I ba...

Alrighty, so as it turns out it's an AB165 circuit board despite the AA165 label. That explains a lot. I've worked through the various mods outlined on these sites... http://www.tone-lizard.com/Bassman_Modifications.htm http://fenderguru.com/amps/bassman ... FWIW, I prefer the oddball NFB, implement...

Fender was notorious for changing circuits, but sticking the previous circuit tube chart in the cabinet 'til the obsolete charts were used up. I was figuring it was one of those scenarios. The 65 onward bassman had that big 27k dropper to the last B+ node, which the AB763 guitar amps didn't have. F...

Filter caps have recently been replaced, the work looks professional. It's not that I'm looking to use bad tubes, I was just really surprised at how a bad tube in the Bass channel effected the sound/performance of the normal channel. Just wondering why or how that happens. Also strangely having the ...

Hey Pete, the cabinet is identified as AA165, however I've noticed some discrepancies in the circuit between v1b and v2. So I'm not sure if someone converted it to AB165 (there's some newer components). I didn't realize there are three distinct bassman schematics until after I posted. By lower outpu...

Hello hello, usually I post over at el34world but the site seems to be having some problems so I thought I'd mosey on over here. I'm fixing up a friends BF bassman, mostly everything is fine. He picked up some vintage RCA tubes from ebay, to make a long story short, through trial and error I figured...