Master Effects is a boutique guitar and bass pedal maker based in Calgary, Alberta, Canada, operating as a one-person shop that designs, develops, and hand-assembles every unit. The brand focuses on utility-oriented circuits aimed at tone-conscious players, with an emphasis on preamps, EQs, boosts, overdrives, and distortions rather than trend-driven effects.

The lineup includes overdrive and distortion pedals such as the Nerve Agent, Martyr, and Warmonger, EQ units like the EQFH, PMEQ, and EQ4H — the PMEQ drawing its voicing from the Aphex EQF-2 console EQ associated with Metallica's Master of Puppets — and preamps including the Thespian and JC Pre. On the bass side, the catalog runs from the Super Forty through the Super Eight Hundred Plus preamps and EQs. Master Effects also offers custom finishes, artwork, and mod work on existing commercial stompboxes.

Master Effects has 8 products cataloged on Equipboard, including Equalizer Effects Pedals, Chorus Effects Pedals, and Preamps. Their gear is featured by 2 artists, with the strongest followings in Rock and Metal. Notable users include Ola Englund and Jack Bates.