CPU Software

CPU Quad

Every dimension
off the hardware.
Every algorithm off the ROM.

A working emulation of the 1989 Alesis QuadraVerb, firmware 1.07 - five reverb algorithms, delay, pitch and EQ, running at the hardware's own 41,666.67Hz clock rather than a resampled approximation. CPU Quad reproduces that same signal chain algorithm-for-algorithm as a modern effects plugin.

CPU Quad reverb plugin - program select page, Alesis QuadraVerb emulation CPU Quad reverb plugin - REVERB page, classic Alesis QuadraVerb reverb algorithm CPU Quad effects plugin - DELAY page CPU Quad effects plugin - PITCH page CPU Quad effects plugin - EQ page CPU Quad effects plugin - MIDI page

Showing REVERB

Sample rate
41 666.67 Hz
The machine's own clock, not a resampled 44.1.
Platform
macOS · Windows · Linux
macOS 10.13+, Intel/Apple Silicon. Windows 10/11, 64-bit. Linux via .deb.
Reverb types
5
Delay-line partitions read out of the firmware, one per type.
Availability
Buy now - £19.99 + VAT
Via Lemon Squeezy.

Hear it

In Your DAW

CPU Quad plugin - PROG page, hybrid rack and parameter view CPU Quad plugin - REVERB page, hybrid rack and parameter view CPU Quad plugin - DELAY page, hybrid rack and parameter view CPU Quad plugin - PITCH page, hybrid rack and parameter view CPU Quad plugin - EQ page, hybrid rack and parameter view CPU Quad plugin - MIDI page, hybrid rack and parameter view CPU Quad plugin - MIX page, hybrid rack and parameter view CPU Quad plugin - MOD page, hybrid rack and parameter view CPU Quad plugin - NAME page, hybrid rack and parameter view

Showing REVERB

Everything 1989 lacked

Tempo sync for the delay times and the LFO speed - the hardware has no idea what a DAW is - a preset bar for browsing patches from the host, and a constrained randomiser shaped to produce a patch worth keeping rather than silence or mud. All three live on the chrome strip above the plate, deliberately separate from the modelled panel.

Registration. No copy protection, and nothing is gated behind it - the plugin is fully functional the moment you install it, offline included. A purchase includes a registration code: entering it needs an internet connection for that one moment, to check the key and show the plugin as registered to you - after that it never checks again, ever. Skip that step and nothing changes: every feature still works, with no trial period and nothing held back.
Not an Alesis product. CPU Quad is an independent emulation and carries no Alesis endorsement. The ALESIS wordmark and the QuadraVerb logo are trademarks and neither is reproduced here or in the plugin.

Support and enquiries: input (at) cpurecords.net