The Highland Dynamics BG2 Mono is an all-tube, fully transformer-balanced vari-mu compressor with automatic leveling capability.
It has a front end in the style of a British-modified Altec 436 with a twin 6V6 output amp in the style of an RCA BA6A or Gates. It contains custom, oversized transformers, US and European capacitors and a US Simpson meter.
The BG2 has standard 600 ohm input, or 150 ohm for more gain and transformer color. It's also useful when running a microphone directly in with no preamp.
Feedback & Compression
British & American Modes
British mode utilizes a modified Altec 436 plate-to-plate style feedback. With less gain, a cleaner, more hifi sound and smoother operation, British is the big smooth tube compressor. American mode lets more harmonics and color come through, instantly changing your compressor to a different animal all together.
There is a compression on/off switch that removes the side-chain tube, turning the compressor into a line amp. With the compression turned off, you can drive it into distortion. You can achieve different colors of distortion with both the feedback and input selection switches.
Two BG2s can be linked with a 1/4" guitar cable in the back of the compressor and the link switch on the front.