TwinStomp S21 Overdrive

The name TwinStomp might be new to us, but this UK-based company is gaining a reputation for its line of pedals. The most recent is the dual-channel S21 Overdrive.

Unlike a lot of boutique builders, TwinStomp makes its own pedal casings. So bid farewell to the generic project box, and say hello to a cast stainless steel lump of a housing. It has four rubber feet, which can be removed, turning the existing 'ears' into mounting holes if you want to bolt it to a pedalboard.

"We're impressed with the sound of the overdrives, which take you from a smooth clipping to a thicker blues sound."

TwinStomp has also designed a patent-applied-for battery holder, so getting the juice into the pedal doesn't involve any screwdrivers or fiddly battery flaps. Instead, there's a metal keyring-style loop attached to a plastic cable-tie.

The battery presses into place, and you pull the metal ring to pop it back out. Easy.

The S21's first channel offers less gain than the second, but both can give a clean boost if you want to drive the front of your amp harder. We're impressed with the sound of the overdrives too, which take you from a smooth clipping to a thicker blues sound. TwinStomp says that channel two has more 'edge', but it's a subtle difference to our ears.

It is an overdrive rather than a distortion, but the second channel could benefit from having slightly higher gain. But still, if you're after a 'drive pedal with character, this is worth a try.

MusicRadar Rating

4 / 5 stars

Excellent sound and build quality.


Gain could be higher.


High-calibre 'drive pedal that's worthy of your attention.

Country of Origin


Available Controls

Channel Select Button Drive Level Tone

Battery/Adaptor Type

9V Battery

Unit Power Source

9V DC Adaptor

Review Policy
All MusicRadar's reviews are by independent product specialists, who are not aligned to any gear manufacturer or retailer. Our experts also write for renowned magazines such as Guitarist, Total Guitar, Computer Music, Future Music and Rhythm. All are part of Future PLC, the biggest publisher of music making magazines in the world.

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