CLMS

Name: CLMS
Price: 12.48 USD
Author: HoRNet

by HoRNet · Utility · Constant-loudness mixing monitor

Not rated yet

CLMS is a pair of plugins, Send and Receive, that keep perceived loudness constant while you mix, so a louder setting doesn't fool you into hearing a better one.

It measures loudness in LU and adjusts level in real time, and it includes a LUFS normalization utility. It costs €10.99 (about $12.48).

Best for: Mix Bus, Mastering. Genres: all genres.

Keywords: mixing, metering, bus processing, mastering, utility, full mix, reference & monitoring, mix bus.

What it does

CLMS (Constant Loudness Monitor System) is a pair of HoRNet plugins that keeps perceived loudness constant while you mix. The developer built it to solve "loudness deception": the habit of hearing a louder version as a better one.

Send plugin: placed before your processing, it reads the track's loudness in LU and stores it in a shared memory area.
Receive plugin: placed after the processing, it compares its own input loudness with the Send's reading and applies the gain needed to match.
Multiple Sends: several Send instances can run in a session, but only one talks to the Receiver at a time over a mutually exclusive channel.
Communication switch: a button to enable or disable the link, so you can hear the real level change when you want to.
Loudness display: continuous LU readings on both plugins.
LUFS normalization: set a target level, press Analyze to record the average loudness, then enable normalization to bring the signal to that target.

The current version is 1.1.0. The demo silences periodically and does not save settings or respond to automation.

Source: HoRNet product page

When to use it

CLMS is the pick when you want level matching to happen automatically across a whole processing chain while you work. Unlike Youlean Loudness Meter 2 or LEVELS, it is not a delivery meter: it shows only LU readings, with no true peak, loudness range or platform targets. Compared with Metric AB, which matches your mix against reference tracks, CLMS matches a chain's output against its own input, so EQ, compression and saturation moves are judged on tone rather than volume. Compared with the auto-gain built into single plugins, CLMS covers any chain of plugins between the Send and the Receive, and it costs very little.

Best for: honest before/after decisions on a channel or bus chain while mixing and mastering.
Genres: any style.
Look elsewhere if: you need a full loudness meter for delivery (Youlean Loudness Meter 2, WLM Plus) or reference-track matching (Metric AB).

Where to buy

HoRNet: $12.48 (Listed at €10.99; converted at €1 = $1.1355 (ECB rate, 29 Sep 2026))

Tutorials and reviews

HoRNet plugins CLMS Constant Loudness Monitor System Demo

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