The 68th installment of the Truth About Vintage Amps with special guest Jef Brown! Use the discount code TRUTHV150FF to save $15 off Caddis readers between now and April 30, 2021.  Some of the topics discussed this week:  7:30 The details you should never annoy your amp tech with 12:23 El Pato references, explained; the El Pato-Tone practice amp (almost sold out); Knorr bullion cubes 19:19 A reissue Fender Twin Reverb with an irritating noise floor and vibrato 23:42 What to do with old 2 ohm Rola speakers; funky capacitors from a vintage Yamaha organ 30:96 Special guest: Jef Brown (Leighton Amplifiers; Southside Guitars) with more amp hacks and troubleshooting knowledge: The 3.3 meg resistor mod to 5E3s (revisited); Southside Guitars; Gibson KEA amp hacks; chokes in a power supply; a Super Reverb soaked in WD-40; new parts gone bad; a buzzy Princeton Reverb; a Fender Tone Master with misplaced grid stop resistors; a Marshall Plexi with a bad LCR filter cap; lead dress; filter caps on a clone Princeton; when to move on from a new speaker; using Fela Kuti/Burning Spear to break in a new speaker; the proper way to wire a three-prong cord to an amp with a fuse.   Technical Note: Around 28:00, Jason's good mic somehow stopped working. Thankfully, this episode becomes the Jef and Skip show shortly thereafter so it won't affect you too much. There's a lot of deep knowledge in this episode; dig in!  Support the show as a TAVA Patreon patron and get bonus episodes, in-depth articles on amp circuitry and other surprises. Email or send us a voice memo to: podcast@fretboardjournal.com or leave us a voicemail or text at 509-557-0848.