MANTISSA, PRESS INFORMATION
Sliding Cheesecake Records
Updated 14 October 2026

In one line:
Mantissa is a free digital reverb modelled on a 1978 studio rack unit,
for macOS and Windows.

In 50 words:
Mantissa reconstructs the halls, plates, chamber, room and chorus of a
1978 studio reverb and runs them at 20.48 kHz through models of its 12-bit
converters. A 1984 era widens the bandwidth. It has 56 factory presets and
predelay in note values. Free, in VST3, AU and CLAP.

In full:
Mantissa is modelled on a studio digital reverb first shown in 1978. It
reconstructs the original's eight reverb programs and its Chorus program with
their defaults and predelay ranges. It runs them at 20.48 kHz, the rate the
original most probably used, behind steep filters at about 8 kHz, through
12-bit converters that choose one of four gains before every sample, so
each sample is a 12-bit mantissa with a 2-bit exponent (hence the name). Its
delay memory clips where a 16-bit word would, and with Stepped on its gains
move in steps of 1/32.

The panel has the original's controls and ranges: separate Bass and Mid Decay
from 0.6 to 70 seconds, Crossover, Treble Decay, Depth, Diffusion and
Predelay, with Mode Enhancement and Decay Optimisation on their 1 to 16
settings. With Stepped on, the decay and filter faders land on the original's
31 values each.

A 1984 era runs the same programs at 34.13 kHz with about 15 kHz of bandwidth,
and Clean takes the converters out. A second fader page adds Size,
Definition and Stop Decay from the later hardware, with Drive, Spread and
Output. Version 1.0.0 also has a Mix control, 56 factory presets, eight
registers shared between instances, settings saved as an audio "tape", and
predelay in note values at the host's tempo.

The original's algorithms were never published. Mantissa was built from
the 1980 service manual and published papers on networks in its designer's
style, then fitted program by program to renders of a reference. A page on
the site compares it with the original card by card, shows the measurements
and lists where it still differs.

Formats and platforms:
VST3, AU, CLAP and Standalone on macOS 11+ (Apple silicon and Intel).
VST3, CLAP and Standalone on Windows 10+ 64-bit.
Price: free. No account required to download.

Product: https://slidingcheesecake.com/plugins/mantissa
Against the original: https://slidingcheesecake.com/plugins/mantissa/original
Download: https://slidingcheesecake.com/plugins/mantissa/download
Manual: https://slidingcheesecake.com/plugins/mantissa/manual

In the press kit:
screenshots/mantissa-full.png         the panel, fader page 1 (2240 x 1320)
screenshots/mantissa-page-2.png       fader page 2
screenshots/mantissa-mainframe.png    the mainframe view
screenshots/mantissa-programs/        the nine programs' responses to a click

About the developer:
Sliding Cheesecake Records is an independent, one-person audio plugin
developer in Brighton. Its plugins are written in C++ with JUCE for macOS
and Windows. Drift Delay and Mantissa are free; Swirl Chorus is a paid
product.

Press contact: hello@slidingcheesecake.com