Judge in his workshop at Vernon Street Studios
Bob Judge is a guitar amp builder and technician based in Somerville, MA. He's the founder of Judge Amps, his boutique amp company, which he operates out of a room in Vernon Street Studios in Somerville's Central Hill neighborhood. Judge is a staple of the Boston music scene, maintaining and building amps for local and touring musicians as well as audio engineers and hobbyists.
While in the studio last month, I turned on my Fender Tweed Twin amplifier and heard a loud bang, followed by a plume of smoke. I brought in to Judge for a fix. Bob met me at the sticker-covered door on Vernon Street, led me down the hallway, and opened the door to reveal stacks of tube amps, reclaimed wood, and heavy machinery. Bob lugged the Twin amp to the back of the room and set it down on his bench. As he removed the chassis from the cabinet of the Tweed Twin, (and cracked a diet Mountain Dew), I asked him to tell me a bit more about Judge Amps.
RD: Bob, what got you into building tube amps?
BJ: I love how they sound. I'm not a great guitarist, but I know what sounds good. I also love problem solving and most importantly, I'm willing to take the risks. Vacuum tubes require a very high voltage to operate--between 400-600 volts--and if you mess up, something could explode, burn, or kill you. There's real dangers in repairing amps and I've often felt like I'm the only person in my circle willing to do it.
RD: "What's the story behind Judge Amps?"
BJ: "I believe it was officially 2019. I started out doing repairs for myself and a few friends, then that became repairs for friends of friends. Until one person brought me an entire amp collection. That really kicked things off for me. He had all these old tube amps, half of which were broken, and he just wanted to move them. I started taking pictures and documenting [the repaired amps] and for the first time I thought, 'okay, I could make a living doing this.' After doing repairs for some time, I started taking commissioned builds. My first builds were a budget Sunn Model T clone and a simplified Fender Blackface amp, which I still make today."
The Judge BL20R. "An improved and stripped down version of mid-1960's black panel style American tone," according to Judge.
RD: "Tube amps are a kind of anachronism. The fact that musicians and audiophiles still covet this technology from the turn of the 20th century is pretty remarkable. What do you think keeps people coming back?"
BJ: "It's harmonics. Tube amps aren't efficient at just increasing the main note, but creating even order harmonics around the note and that’s pleasing to our ears. Tubes do an especially good job of creating those harmonics as they’re made less and less efficient by turning up an amp's volume. So if you turn it up, instead of just getting more volume of your note or expected frequency, it creates more of these harmonics."
RD: And eventually you get that tube-driven breakup. Gah! What about this work inspires you?
BJ: Creating new stuff is exciting for me. Even if it’s not an amp. I just bought a laser cutter that I’m kind of battling with to get it to work right. I hate working on the same thing over and over. If I got really successful selling my amps, I don't think I could make the same amp over and over again. I also like the challenge of having repairs and seeing old junk that may be considered trash to some people, and giving it a new life, letting someone enjoy it again. Keeping stuff out of landfills is important to me too. I like being able to repair things in a throwaway culture.
RD: As we head into the new year, what was a standout moment for Judge Amps in 2024 and what ambitions do you have for 2025?
BJ: I built a new amp design and though it seemed to be working, I expected it to sound way better. Rather than going back to the drawing board, I trusted my design and figured I must have done something wrong. I found I missed a part and after fixing it, the amp sounds incredible. It was satisfying to troubleshoot with faith in my own design and have the amp turn out as well as planned.
Next year, I'd love to sell more of my products, but they're difficult to hear let alone try. So I want to go into the studio, record them well with an engineer, and kick off the new year with some new audio [demos] of my amps.
RD: Neat, Bob. I have to ask. What's your favorite tube amp of all time?
BJ: The first Marshall 2204 JMP Master Volume amp, which was rebranded as a JCM 800. It has a great clean and sounds amazing when pushed with an overdrive or basic boost pedal. My GD20 is a modified, lower-wattage version of that amp and I think it improves upon the good qualities of the original.
RD: Love those amps. Speaking of, what do you think is wrong with mine?
BJ: Shorted output tube probably. Your resister blew. Should be a quick fix.