Carl Martin Ampster review: A valve-driven pedalboard amp offering realistic tones in a pocketable package

This pint-sized powerhouse puts the roar of a half-stack right at your feet. But will it replace your regular rig?

Carl Martin Ampster
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Review Overview

Our rating


Our verdict

Verdict: A great way to downsize your backline without compromising on volume or tone.

If you’ve ever found yourself in the predicament where a 4×12 cab meets a narrow venue staircase or a cramped hatchback, you may well have cursed your love of big amps. Enter the Carl Martin Ampster, which aims to solve an age-old dilemma.

There are a fair few amp-simulating pedals out there already – from the Neural DSP Quad Cortex, with its deep-editing capabilities, to the analogue Orange Terror Stamp, with its emphasis on ease of use. The valve-driven Ampster sits squarely in the ‘keep it simple’ camp, but brings a few unique features.

This pedal-sized amp aims to deliver a decidedly traditional feel that negates the need for menu diving. Master volume, presence, gain, bass, middle and treble controls adorn the front face, making it look instantly familiar to any guitar player.

Carl Martin Ampster

But there’s also a footswitch for hopping between 2×12 and 4×12 cab types, as well a voicing switch round the back for even more control over the low end. You get a comprehensive set of connection options, with an XLR DI output for hooking up to a PA or going into your audio interface, as well as an effects loop for pedal connoisseurs. The small size and tactile nature of the Ampster mean it will feel just as much at home on a studio desk going into your DAW as it will attached to your pedalboard on stage.

In use

One of the best things about the Ampster is how immediate it feels. The controls are easy to get to grips with, making dialling in a wide range of tones nigh-on instantaneous. Driven by a single preamp tube, it reacts remarkably well to dynamic picking styles – in the midst of extended playing, you might well forget that the sound is coming from the PA and not your regular amplifier.

As a standalone unit, the Ampster works very well. Keep the master volume high and the gain low and spanky clean tones abound; crank the gain knob and you’ll unlock some tasty Marshall-style crunch. With the four EQ controls there’s plenty of scope for different flavours of tone. Where this thing really shines, though, is at the end of a chain of pedals.

Carl Martin Ampster

When we combined it with a Rat-type distortion and a clean boost we got pummeling rock tones that sustained for days, pushing into feedback just like the real deal. Dialling in some shimmer reverb and a healthy dose of old-school chorus via the effects loop proved similarly fruitful, celestial sounds filling the room from our studio monitors.

Switching between the 2×12 open-back and 4×12 closed-back cab options also gives an appreciable difference in tone, making it easy to tighten up the unit’s bass response when required. It’s a shame you can’t load digital impulse responses, nor bypass the cab simulation entirely, but that’s not really what the Ampster is about.

All it’s here to do is fill the gap between simplistic pedal-sized preamps and ultra-complex amp-modelling units, enabling you to dial in great guitar tone quickly.

Carl Martin Ampster

Key Features

  • PRICE £239
  • DESCRIPTION Analogue amp pedal, made in China
  • CONTROLS Master, presence, bass, middle, treble, gain, cabinet footswitch, mute footswitch, voicing (low cut) switch, ground lift switch
  • FEATURES 1x ECC83 valve, balanced DI out, effects loop send and return; powered by 9-volt mains supply only (1000mA)
  • DIMENSIONS 145 x 120 x 70mm
  • CONTACT carlmartin.com

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