Derek is the audio applications engineer at Pacific Transformer. He's the go-between for amp builders and our engineering team, and he built the 5E3 tweed Deluxe we gave away last year. In this episode he explains how players' words like "bite," "squish," and "feel" become transformer specs.
Derek started building amps during COVID, when he couldn't find a local amp tech with a reasonable wait. He has an electrical engineering background, lives in Fullerton, and has restored more vintage Fenders than he can count. Now he designs his own amps, and his rule is to never build something someone else has already built.
IN THIS EPISODE:
• His first two builds. The "Nino" is part tweed Deluxe and part brown Deluxe. The "Compadre" is a 35-watt amp with two 10" speakers, based on the tweed and brown Supers. He still calls it his best amp.
• Why he skips vintage parts. He uses new components so an amp can be serviced for decades. He also thinks about 70% of an amp's sound comes from the speaker.
• Mixing speakers. He likes one ceramic and one Alnico speaker in a 2x10 or 2x12 cab. He also talks about his custom Weber speakers.
• Output vs. power transformers. How plate voltage, primary impedance, and the output transformer affect headroom, saturation, and how the amp feels to play.
• Decoding customer requests. That includes forum posts and ChatGPT transcripts people email in. He says the AI answers are "nearly always wrong."
• Replacing a discontinued transformer. Why a basic data sheet isn't enough to copy one, and why starting from a close existing design gets you about 90% of the way.
• Dumble vs. Trainwreck. A Dumble is like an RV with every option. Ken Fisher's Trainwreck is like a stripped-down race car. Derek says every other amp builder falls somewhere between the two.
• Our NAMM booth test. We compared two new '65 Deluxe Reverb reissues, one with stock transformers and one with Pacific transformers, and explains why the stock one sounded thin.
• What made the giveaway 5E3 special. Very careful grounding for a quiet amp, stronger power filtering, a balanced phase inverter, and smaller coupling caps to cut some bass.
• Pick the next build. We're doing another giveaway. The candidates are a modded Marshall 18-watt, a brownface Deluxe, an AC15-style EL84 amp, and a blonde Bassman. We're also talking about building a Trainwreck-style house amp for NAMM with the original OEM transformers.
CHAPTERS
00:00 Intro: Derek's role at Pacific Transformer
01:52 Getting into amps during COVID
03:16 The Nino, his first scratch build
08:42 Mistakes from the first build
09:54 No vintage parts, and why speakers matter most
14:01 The Compadre
16:30 Turning tone words into transformer specs
22:12 Replacing a discontinued transformer
27:29 Trainwreck vs. Dumble
31:36 The NAMM booth transformer test
36:24 The giveaway 5E3 tweed Deluxe
45:36 Candidates for the next giveaway
59:43 A Trainwreck-style house amp for NAMM
Vote for the next giveaway amp, and tell us what you'd change about it.
