Update — October 2025: I've been laying low while recovering from knee replacement and getting healthy. Mod work will resume after I'm healed, most likely after the first of the year. I have a steady full-time job, so FJA work happens on weekends — emails may not get answered right away during the week. Many older mods are no longer available; email to check what's still offered. I'm focusing on popular, less involved mods. Prices on the site may not be current — I'm updating as time allows.

Delivering the Tone

Since 1990

Custom built tube amps, amp mods, restoration, and repairs. Un-modding hacked mods done elsewhere. Pedal mods, guitar work, and custom tone — one shop, one guy who gets it.

Email Jerry Browse Amp Mods

What We Do

From Plexi-era Marshalls to modern high-gain — mods tailored to how you play, not chasing someone else's CD tone.

Tube Amp Mods

Marshall, Peavey 5150/6505, EVH, Mesa, Soldano, and dozens more brands. Gain, voicing, loops, and channel switching.

View amp mods →

Repairs & Restoration

General repairs, maintenance, bias checks, and fixing mods done wrong elsewhere. Keep your amp reliable on the gig.

Get in touch →

Pedals & Custom

Pedal mods, custom builds, switchboxes, and guitar modification. If it makes noise, we can probably improve it.

Products & pedals →
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Popular Mod Pages

Rectifiers, Plexis, 5150s, and more — email for current availability and pricing.

Marshall

Plexi, JCM800, DSL/TSL, JVM — from gain boosts to extra stages and loops.

Marshall mods →

Mesa Boogie

Rectifier, Road King, Mark series, Stiletto — clarity and voicing mods.

Mesa mods →

FJA Custom Built Amps

Custom built tube amps designed and built in the FJA shop — your tone, from the ground up.

FJA custom amps →

Peavey 5150 / 6505

Clarity, metal, bias, and channel mods for the classics.

5150 mods →