THE PHILLY 20 & Philly 20+

When I started repairing amps in Philadelphia the majority of the amps that came into my shop were of the 60’s cAliForNiaN variety (fender black/silver panel). I learned through repairing these amps, and subsequently, they became my standard from which to judge every other amp. But I had my complaints ---- I wanted these amps to distort earlier or with less hesitation. But more gain comes with drawbacks, and can throw off the whole “recipe”. Where to turn things down, or crank things up in respect to gain, or how much bass to cut/pass – it takes a lot of trial and error >>> I have been designing, prototyping, building, selling, and subsequently rebuilding some version of this amp circuit since 2013. I’ve added tubes, channels, switches, and controls, and have taken many out. I’ve tweaked almost every value from the original circuits and have made some drastic changes. The result?

A revoiced, harmonically-rich version of the circuit I cut my teeth on.

These simple, yet versatile amplifier circuits can be built in a variety of cabinets/ways, but always include:

·       F&T / Sprague electrolytic & SOZO / Mallory coupling capacitors

·       Mercury Magnetics transformers (Made in the USA)

·       JJ 6V6’s (JJ 6L6’s for Philly 20+) from Eurotubes

·       A variable mids/gain BOOST control)

·       terminal-strip (closest to actual point-to-point wiring possible) construction

·       cathode-biased power tubes for both easier replacement & less reluctance to overdrive

·       “more than necessary” power ratings on all resistors

·       optional all-tube spring reverb (+$200)

·       footswitchable boost and/or reverb (footswitch included)

Pricing: Please email for current pricing —> pricing is dictated on current wood and woodshop prices, if the amp has reverb, and other small details (based on customer input).

HOW TO ORDER? Send an email to info@RootbeerAudio.com /// A 50% deposit (PayPal or Venmo) is required to start the build. The remaining 50% balance (+ shipping) is due upon completion.