ALLHaas

Name: ALLHaas
Author: Florian Mrugalla

by Florian Mrugalla · Imaging · Allpass stereo widener

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ALLHaas is a free stereo widener from Florian Mrugalla that uses many allpass filters per channel to place elements in the stereo field, with L/R and M/S modes.

It is free and open source (GPL 3), as VST3 for Windows.

Best for: Keys & Synths, Guitars, Vocals, Mix Bus. Genres: all genres.

Keywords: wide, free, mixing, open source, mid/side, mono-compatible, electric guitar, reference & monitoring, synths, bus processing, full mix, mix bus, vocals.

What it does

ALLHaas is a free stereo widener that uses phase shifts instead of delays. The developer says it "essentially uses a ton of allpass filters to let you place elements in the mix."

Distance: sets how many allpass filters are applied on each channel; more filters shift the sound further.
Cutoff: sets the frequency the allpass filters centre on, per channel.
Resonance: sets how wide or narrow the affected range around the cutoff is, per channel.
L/R and M/S modes: process the left and right channels, or the mid and side signals, separately.
Mono check: a mono compatibility button for checking phase problems.
Display: a central display shows the signal being processed.

Version 1.0 was released in January 2024 and is free and open source under the GPL 3 license, downloaded from GitHub.

Source: Florian Mrugalla product page

When to use it

ALLHaas is a good free pick for users who want to nudge parts left, right or wider using phase shifts rather than delays. Compared with Ozone Imager and S1 Stereo Imager, it has no multiband control or correlation metering, only a mono check. Compared with Wider, it gives more hands-on control through per-channel distance, cutoff and resonance, but takes more care to stay mono safe.

Best for: placing dry synths, guitars and backing parts wider or off-centre in the mix.
Genres: any.
Look elsewhere if: you want metering and band control; Ozone Imager or Wider are better choices.
Tip: the effect is subtle on reverb-heavy sources and strong on dry ones; the developer notes it can take away some tone, so check in mono (per Bedroom Producers Blog).

Where to buy

Florian Mrugalla: Free

Tutorials and reviews

Mrugalla ALLHaas: Free Stereo Widening VST Plugin

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