Angela Intruments - Tubes, speakers, transformers, and other parts for vintage guitar and bass amplifiers. Also instrument parts. www.angela.com
Ferrantronics Guitar Amplifier Repair - Guitar amplifier repair and mods since 1970. In Chicago and Northwest Indiana. All music electronics repaired. Ferrantronics Tube Preamplifier. ferrantronics.com
Time Electronics - Guitar and bass amplifier repair and mods. www.timeelect.com
