I finished my last build, of a mini amplifier, but this time with a proper guitar speaker. Since I was going small the jensen 6" was my choice.
On the way I added a meter on the front just to add some nice vintage measurement instrument look.
Made some solidworks experiments and ended up with this:
[img
[img
After that I worked on the real box, that I got from Ikea.
The circuit is a simple trifty croaker, since I started with the savage croaker.
The meter was a little difficult because it needed a driver circuit, that need to be single supply since I just rectified the filament supply for it.
I ended up using an opamp with some diodes to adapt the movement from linear to log. It shows the preamp signal, so on full blast it hits the rigth end, and clean it stays in the middle. The meter was an old ammeter that looked nice and still worked. The resistance was in the 200 ohms range, so it looked ok fo the circuit.
Some pictures of the final stage>
[img
[img
The output is the VVR circuit applied to the el84 screen, get kind of fuzzy when down, but who needs another fuzz pedal.
[img
[img
Almost forgot the gut shot, it's a mess...
[img
Still need to finish the schematic and make a video. Still doing some simulations with the meter driver circuit to obtain more movement at lower gain/volume settings.
For now I'm happy with it, as I said, at lower voltage settings it sounds very fuzzy, really nice to play, and with the guitar volume I can control it to obtain more of a crunchy sound.
Cheers,
Thomas