Ruby amp varients built into public announcement speakers

A deserted healthcare center was the source for these speakers.

I knew these would be really cool for Runoffgroove’s Ruby amp builds and so I took a bunch home. This was a perfect opportunity to compare different builds with the same speaker configuration. What’s nice about these amps is that you can crank them up to 11 and still be able to play in your bedroom without having your door smashed in.

These speakers aren’t hi fi, but they do the job better than I expected.

I have since acquired some automotive power amp chips. Roughly 4 times more powerful than the LM386 used in these circuits. I’m currently experimenting with designs that I hope to use in the remainder of the speakers. I’m also experimenting with designs more suitable for bass guitar and keyboard use although I don’t expect these speakers to shine at either..

I love the way these things look and sound, and I love the portability. The circuit is ridiculously simple, could be a first build for anyone and is very gratifying at that.

Two variations are presented here, the standard built, and the ‘Bassman’ mod (which I like best). I also built the three knob ‘Noisy Cricket’ as presented by Beavis Audio, but my dad snagged it (along with my BC Rich) in order to see if he can “figure out that electric guitar thing”, so I don’t have it in my video comparison. I run them with 9V wall wart although they could easily be run with 4 AA batteries or a single 9V.

The video also features a short mix test. I used the ‘Bassman’ version for it. The only other thing I have running between the Telecaster and the amp is a Yamaha OD-10MII overdrive pedal set as a booster (no pedal overdrive added). I increased the boost a little for the solo part.

I think all in all it sounds pretty good, although the rust in my fingers is clearly showing.. must have been dedicating too much of my time to soldering..