The Koch ST20/H Studiotone is a compact yet exceptionally powerful 20W Class A tube amplifier head with a versatile tone reminiscent of classic British amplifiers from the 1960s. Thanks to two EL84 output tubes , three fully switchable channels (Clean, Overdrive & Overdrive+) and clever voicing options, this top-of-the-line amplifier offers everything from warm, round cleans to saturated, dynamic overdrive with real tube compression.
The Mid Shift (2-way) and Bright (3-way) switches allow you to easily tailor your sound to any playing style. The rear panel offers extensive functionality: a recording output with speaker simulation , direct outputs (including headphones), a Power Soak , and a speaker on/off switch for silent recording or practicing. Thanks to the serial effects loop , spring reverb , and multiple speaker outputs, this amp head is equally suitable for recording sessions and live performances.
Specifications:
- Type: Class A tube amplifier head
- Power: 20 watts
- Output tubes: 2x EL84
- Channels: 3 (Clean, Overdrive, Overdrive+) – switchable via footswitch
- Tone Controls: Passive Bass, Mid, Treble
- Voicing switches:
- Mid Shift (2-way)
- Bright (3-way)
- Reverb: Spring type (Short Hall, 3 springs)
- Effect loop: Serial, -10 dBV
- Recording output with speaker simulation and two voicing filters
- Direct outputs:
- Unfiltered
- Clean channel
- Headphone out
- Speaker outputs: 4, 8 and 16 Ohms
- Speaker on/off switch
- Power Soak function
- Included: 2-way footswitch
- Dimensions: 44 x 23 x 24.5 cm
- Weight: 10 kg
