Guitar Amp

I've always avoided a specific 12v electric guitar amp, as I generally do acoustic acts, and anyway, electric bands are noisy and always want more power than is available... normally as mains, too. At least if I supply a guitar amp there's an alternative.

Also, the bright input of the bass amp has sufficed in the past, once we get past the teenage strops of the guitarist, in one case. I don't know who was more insulted, me or the bassist they refused to share with... admittedly it's not ideal.

I only built this as I realised I already had all the bits. The box - more or less a 12" cube with a partially open back - and the speaker, a 10" 50W Celestion guitar speaker were left over in the remains of a home built main amp from my active band days (the top of the box was replaced to allow for the preamp panel and the result repainted with blackboard paint, though). Amp was yet another smallish car booster amp - this one £3 in a car boot sale, I think - and the otherwise potentially hard bit of the preamp was solved by buying a cheap 10W amp from Thomann.de - it was a mains-only version of an amp they also did as battery powered (but a lot less, I was likely to be taking it to bits anyway) - the CG-10X - for £28 you got a 6" speaker, clean & dirty channels, and rudimentary chorus & delay. They'/ve even handily labelled the preamp PCB edge connector with everything I needed - amp, gnd, power - so it was almost trivial to wire all the bits together. I did need to add a capacitor in the audio feed from preamp board to the car amp - obviously unblocked DC, on the output, but that's not a problem.



It's quite an amp - loud, solid sounding, a decent clean sound, and of course the effects to play with - once you've done the Cocteau Twins & Ozric Tentacles impressions it's tempting to turn them off, but they're useful to have, along with the comprehensive EQ. They do a more basic version of the amp (CG-5), the preamp of which would probably do just as well, but this one wasn't much more. One thing I'd like to add is an isolated balanced output for PA use across the preamp output, but one day, one day.

I'm torn, of course, about making use of cheap electronics from China, and buying such things new - it's hard to avoid some times, but it's good to use what you already have sometimes. One alternative thought has been derived from a Laney practise amp, that used a +/-12v supply. Experiments proved that this could be bodged by using a car laptop supply to give +24; connecting -12 to the battery 0v, 0v to the battery 12 and +12 to the laptop supply 24, if that makes sense. Obviously any connections in & out would need to be referenced to the -12v rail (so that you're not shorting out the battery down the earth of an audio cable), but it could work. This way, though, I get more volume that just a practise amp...