The Custom 20 circuit is designed for not just the usual Hiwatt sweet cleans but to also get fat, harmonically complex overdrive when driven; the twin EL84 power section handles both as well and everything in between at useable volumes. A simple, intuitive amplifier which can be pushed into natural compression and overdrive in response to your guitar controls and playing dynamics - the OTHER great Hiwatt sound. For 2025 we have made some revisions to the circuit by adding a Bright switch and an extra gain boost for even more control options. The Bright switch gives you the option for adding sparkling treble to your clean tones at lower volume, or to tighten up gain tones when wound up; the gain boost works with both High and Low inputs and is designed as a natural boost of the amp's voicing, introducing extra harmonic thickness into the preamp. These two controls are interactive, alongside the High and Low impedance input, to offer new and exciting variations on earlier Custom 20 sounds.