The Blackstar HT Stage 100 tube amp head uses a quartet of selected EL34 power tubes to deliver 100W of British dynamics with 3 channels, delivering 6 modes for amazing tonal versatility. The 'boutique' style clean channel has 2 modes: 'British Class A' and 'dynamic US'. Each of the amp head's 2 ISF (Infinite Shape Feature)-equipped overdrive channels accesses a further 2 modes.

The Clean Channel has 2 modes, 'boutique' and 'modern' and its own Tone control provides a wide range of clean tones. The Voice switch reconfigures both the preamplifier voicing and gain structure, and the power amplifier damping, to reproduce either ringing Class A Performance in the 'boutique' mode, or very clean and tight Class AB tones in the amp head's 'modern' setting.

The Overdrive Channel on the Blackstar guitar amp head has its own EQ section and a Voice switch that allows the character of the channel to be changed, providing a wide variety of overdriven tones. The channel is characterized by a tone that's high in gain, but lacks any of the detached top-end 'fizz' often found in similar designs. This is a result of unique preamplifier and power amplifier shaping techniques, which cleans up the overdrive beautifully as the guitar volume is reduced. Even at the most extreme settings, the overdrive channel remains natural sounding. The Blackstar Venue HT-100H amp head's ISF control is unique to Blackstar Amplification and represents a major step forward in tone shaping flexibility.

The ISF control shifts the response of the 3-control tone stack between a US-type response at one end, and at the other a UK-type response. The Blackstar Venue tube amp head has an infinite number of alternative tone choices in between the 2 extremes that would be otherwise unavailable.

The Blackstar HT-100H amp head also features a completely natural sounding digital reverb, which is outstandingly musical on both clean and crunch tones and raises the benchmark for guitar amplifier specific reverb design. A Dark/Bright switch allows the overall reverb characteristics to be modified to suit different tastes and playing styles.