Acoustic amp schematics

[Andy Le Blanc]

that bogen has a transformer input.

could be a matching issue at the input for different pick up types
how about a passive DI input. at least a hi and low impedance input.

[BTF]

One important thing, as Mr. Le Blanc pointed out, is determining what type of pickup will be used with the amp. This is critical, as most piezo pickups which don't have a preamp need to see an input impedance of 10M, far above the usual 1M or so seen in most tube amps. This is to ensure the pickup is properly "loaded" for fullest sound. The battery-powered preamps will work with most any input.

When I built my current 59 Bassman-based acoustic preamp, I installed a switch to change the input impedance from ultra high to high (10M to 1M). I have to be brutally honest and say that I actually can't tell a huge difference in the two using my Schaller Oysters, but at the time it seemed a necessary idea.

[KellyBass]

Adjustable passive input would be great in this instance...since there's such a wide variety of acoustic pickup types out there. cheapies to Fishmans...

But, It'd be nice to have a Jensen input as well.

This is startin' to sound like a fun project.