|(Click for a close-up)|
Akai's new Hexacomp (C2M) pedal is actually six compressors in a single pedal. The input signal split into 6 bands according to frequency and then fed to the individual compressors. Each compressor operates completely independently, with dedicated control of input gain and compression ratio for each band. The separate bands are then mixed and sent to the output gain control.
Conventional single-band compressors act on the entire input signal. So if you hold a sustained note on a low string while you really hit a high string hard, the compressor lowers the combined volume of both-and you lose the bottom end. But with the Hexacomp, compression is selectively applied to the separate frequency bands, and this means you can compress that popping high note while leaving the sustained bottom end untouched.
Compressors are a great tool for leveling out volume, but they have one big drawback: they lose a lot of the player's dynamics. This is especially true with guitar which has a big peak in the midrange. As soon as this midrange peak triggers a conventional single-band compressor, the entire volume is lowered, losing much of the dynamics of the highs and lows. By applying compression only to the midrange, the highs and lows which are below the compressor's threshold remain unaffected. And this maintains the player's dynamics at the same time as making the volume more uniform, a trick that's impossible with a conventional single-band compressor.
Varying the compression ratios of the separate compressors attenuates the 6 frequency bands individually, resulting in unique phase effects when the signals are recombined. The effect depends on the amount of compression applied to each band and is completely different from the periodic-type phasing produced by phase-shifters, adding extra personality to the Hexacomp sound.
The Hexacomp is true-bypass.