Audio Kitchen The Big Trees - All Valve Class A AmpItem ID: TBT
The Big Trees is a valve-powered amplifier in a stomp pedal format. Two 12AX7s and one EL84 drive a 2.5 watt power transformer, making the Big Trees a full-fledged Class A amplifier.
Picture the Big Trees as an amp head in a pedal chassis. The circuit is styled as a non-master volume amplifier, with controls for gain, "root" and "branch" - bass and treble, respectively. Two knobs labeled Clean and Dirt control attenuation for the speaker output and the line level output. A six position Dirt switch interjects distortion into the clean signal, and also sags the power draw. Go heavy on the dirt, and the pedal will fuzz out - almost similar to a variac Marshall. Only at that point is the Big Trees similar to any other amplifier.
Much like AK's range of amp heads, the Big Trees has a very unique tone and response. It doesn't sound like a Marshall, Vox, or any other known UK-made amplifier. It's Class A power stage gives it a quick attack, and the bias of the tubes adds organic, low-watt sponginess. Cranked up, the Big Trees' volume level is perfect for studio or stage, and the user can also dial back for quieter at-home use without sacrificing dynamics.