During the 2020 COVID lockdown in Australia, I formed a Rockabilly/Blues busking trio. This meant returning to an amplified blues harmonica sound, after a break of some decades. I have a fine Lone Wolf pedal which approximates this classic sound; however, nothing beats a harmonica-friendly valve amp. Time to roll up my sleeves and make one.
BUILDING AMPS Tony Eyres
Not entirely silly - I worked as an Electronics Engineer in the 1980s before moving on. I also taught introductory electronics for some years. I figured this past experience would keep me from stupid mistakes. It did not. More on this later. There is a large community, entirely male as far as I can tell, who build classic 1950s/60s guitar amplifiers. The relatively simplicity of these now ancient circuits, mostly from Leo Fender, makes these enterprises feasible. The glorious sound which results makes the effort (and considerable expense) worthwhile. As I am finding, the projects become addictive. Amp builders like myself gather online at the “Shock Brothers DIY Forum”, on TDPRI.com (Telecaster Discussion Page Reissue). Here folk display their projects (some of which are exquisitely well done), and seek advice when things go wrong. Valve amplifiers routinely produce more than 400 volts DC, waiting to pounce on the inexperienced or careless operator. I treat these voltages with great respect, and hence still have ten digits to type with. In particular, I plan and rehearse measurements before turning the amp on, and unplug it once they are done. Capacitors will happily retain lethal voltages after shutdown, so I install discharge resistors to eliminate this hazard. I warmed up, so to speak, on a 1957 Fender Deluxe guitar amp. The circuit is called a 5e3, the kit which I built came from China. The story of this build (and the failures along the way) are for another day. However, it sounds just mighty with my 1950s Gibson archtop, which I play in my new band, along with my harmonicas, the latter in a Seydel Gecko Rack with the excellent Greg Heumann Rackit! featuring his Bulletini mic. The 5e3 build behind me (until it breaks down), I set on a valve harmonica amp to complement my busking rig. My guitar and vocals go through an AER Alpha, 40 watts of incomparable German engineering. This runs from a 500 watt inverter, connected to a 12 amp hour Lithium Ion battery. I’ve only once run the battery down while playing, the day I brought a Fender Champ out for
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The magazine for HarmonicaUK
