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PEQ-1 RIAA-flexible equalizer

PEQ-1 phono preamp in a wooden enclosure with red and black knobs

PEQ-1 is an active portable RIAA-flexible equalizer designed to be built and replicable with DIY techniques. Due to the high amount of different pre-1954 vinyl playback curves, the EQ also includes the possibility of modifying the low and high filters to help with material equalized with these other curves such as NAB, BBC, AES, Victor-78, Orthacoustic, etc.
Although the PCB and design implementation are mine, the schematic was heavily inspired by Douglas Self’s work on RIAA networks.

PEQ-1 prototype being tested next to a laptop and a computer screen
Etching the PEQ-1 circuit board in a plastic tray
PEQ-1 front panel design with low and high frequency controls
PEQ-1 RIAA-flexible magnitude response plot

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