The GT120's power amp distortion requires high volume to achieve its best tone; it's rated at 120 clean watts before breakup, contributing to its popularity for heavy genres.

The amp uses a Baxandall tone stack with an active shelving EQ, allowing for greater fidelity at low and high frequencies and enabling unique tonal shaping.

The adjustable mid slope in the EQ can produce chimey or moody tones, offering more range compared to typical tone stacks.

Input 1 is for low gain, ideal for bass or keys, while Input 2 is designed for guitar with higher gain settings.

The FAC control alters capacitor values, offering a wide bass range; far left maximizes bass, while the right tightens the tone akin to a Marshall.

The effects loop automatically mixes delay or reverb effects at 40% wet, allowing creative sound manipulation without additional adjustments.

The amp's presence knob helps manage wooly tones, providing clearer high frequencies when needed.

Matamps can achieve classic rock and higher gain tones with the use of external overdrive or boost pedals, adapting their swampy sound to styles like Tool or Helmet.

The GT120MV excels at lower volumes and is suitable for bedroom use, unlike the NMV version which requires higher volume to shine.

Owners report that with overdrive and fuzz pedals, the GT120 can achieve substantial volume and sustain, ideal for doom metal and heavy music styles.

A high gain rack preamp, such as the ART DST 80/80, can be used to introduce modern gain and tightness while retaining the Matamp EQ character.

Some owners find the GT120MV lacks sufficient headroom for loud band rehearsals compared to the NMV version.