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Which vintage amp to build?

Phoenix1

New member
Joined
Mar 11, 2025
Messages
6
A JTM-45 is a beautiful thing. Great cleans with plenty of headroom and some of the best-sounding overdrive you'll find anywhere if you build with the Drake-style output transformer. Just a stellar amp!View attachment 29603
Strange your build looks great but mine had two filter caps which mine might be getting recapped soon as when I turned it on the other day after a year there is a hum coming through. Still sounds good but volumes done affect it. I need to get it down and pull the chassis and test voltages. This was an amp from Tube Depot called a JTM45+ it has a lot of extra garbage I am tempted to redo it as I am a little more comfortable now days as this was my first amp build. I think I could tidy it up a bunch. It has all these voicing switches plus a GZ37 rectifier or Solid state rectifier
IMG_1986.jpeg
 

bern1

Well-known member
Joined
Nov 23, 2004
Messages
1,322
Whichever one you want to play through! That desire will get you through any build.

The first amp I built was a Metroamp JTM45 kit. I really wanted one and at the time there were no reissues that sounded anything like the real thing. George did a great job reverse engineering the amp. Gary Bohannan posted a video of one he had just built on this forum with all the knobs all the way up. Supposedly this was the setting for the Bluesbreakers record with EC. Don't know if that's a true story but the sound of the amp in the video sounded like the Bluesbreakers record and that was what I wanted. When I was finally done with my build, I plugged my Les Paul in and it sounded just perfect!

It's now 20+ years later (or something like that) and I still have the amp. I really don't play at that SPL level any more but it is still the amp I like the most.

Building amps is fun and I am sure you will enjoy the experience!
 

Phoenix1

New member
Joined
Mar 11, 2025
Messages
6
A JTM-45 is a beautiful thing. Great cleans with plenty of headroom and some of the best-sounding overdrive you'll find anywhere if you build with the Drake-style output transformer. Just a stellar amp!View attachment 29603
My JTM 45+ from Tube Depot has a master volume where on of the input jacks is. I am taking it out as it is really useless. In amps built with a master volume the masters just turn up the power section the other volumes turn up the preamp so you can get the sound or crunch and control the real volume with the master. That way is much better as you can get the marshall sound at bedroom levels. The 45s are fantastic but really start sounding great above 7 or 8. just my opinion ! I just stripped mine completely out and with all new and better components rebuilding it. This is a before and after. I did replace all caps with F&T.IMG_3365.jpegIMG_3382.png
 
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