Black Box Analog Design HG2

The HG-2 uses custominput transformers to feed two paths: The main signal path travels through a 6U8A Pentode tube stage that then drivesinto the Triode stage that follows, resulting in everything from subtle harmonics to full on saturation.

Also fed from the input transformer is a parallel signal path that utilizes a set of 12AX7 tubes, voiced specifically for harmonics and saturation. This parallel saturation circuit is outfitted with a 3 way Freq. Select switch that allows the user to choose the frequency content of the signal feeding the circuit. The low position saturates just the low mids and sub frequencies, the flat position saturates full bandwidth and the high position saturates only the high mids and high frequencies. The result is the ability to add top end to dull tracks, enhance low end or enhance and add energy to the entire signal. The harmonics knob allows the user to control how much of the processed, parallel signal is fed into the main signal before hitting the Pentodestage. Finally, both stages reach the passive output attenuation before a pair of customoutput transformers.

In addition to the saturation stages, an air switch adds a subtle top end lift and the alt tube button switches between two different 12AX7 tubes in the parallel circuit. Switching between tubes allows the user to swap tubes for different types of saturation and switch back and forth instantly.

The meter select chooses whether the meter is fed from the input or output, and the bypass switch is a true bypass that shorts the input directly to the output with no additional circuitry in line.