Indigo

Name: Indigo
Author: Acustica Audio

by Acustica Audio · EQ · Tube mastering EQ suite

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Indigo is a five-plugin Acustica Audio suite for mastering, with two stereo tube EQs, a stereo shuffling processor and optical compressors.

It is built around class-A tube circuits with Jensen transformers; the price is not shown on the product page.

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

Keywords: tube, mastering, wide, gentle, transformer, 60s, full mix, glue, hardware emulation, inspired by, modern, vintage, 70s, bus processing, mix bus, samples & loops, static, warm.

What it does

Indigo is Acustica Audio's tube mastering suite: five plugins that sample vintage and modern tube EQs, opto compressors and a stereo image processor. The developer pitches it as a suite "specifically designed for high-end mastering duties", though it works on mixes and buses too.

Stereo Tube EQ (3-band): modelled on a modern, discrete class-A tube stereo EQ with Jensen input and output transformers, plus an Aggression control that adds harmonic colour.
Stereo Tube Mastering EQ (6-band): a finer tone-shaping EQ inspired by a late-1960s Danish tube design, meant for broad, gentle mastering moves.
Stereo shuffling processor: a 10-step stereo field control for widening or fixing stereo mic images, inspired by a Tesla Audio Laboratories unit and 1960s British tube consoles.
Shuffler filters and preamp: switchable high- and low-pass filters (3 or 12 dB per octave) and a tube preamp section with two emulations.
Compressors (mono and stereo): three modes each: A, a 1970s Canadian optical compressor; B, a modern California opto mastering limiter/compressor; C, a hybrid "Frankenstein" that blends the two.

It had a four-week launch offer, and a trial is available. The product page itself gives no version number.

Source: Acustica Audio product page

When to use it

Indigo is the pick when you want a whole tube-coloured mastering chain from one developer: two tube EQs, opto compression and stereo shuffling, all sampled with Acustica's technology. Compared with the Pultec Passive EQ Collection and Manley Massive Passive, it adds compression and stereo-image work in the same suite, but none of its parts claims to recreate one named classic as closely. It is far more coloured than Pro-Q 4 and has none of its dynamic bands, spectrum display or surgical precision. Unlike those EQs, it also includes a stereo shuffler for widening or correcting stereo mic images.

Best for: adding tube warmth, gentle opto glue and stereo width on masters, stems and mix buses.
Genres: any; especially acoustic, rock, jazz and pop masters that suit vintage colour.
Look elsewhere if: you need clean, precise or dynamic EQ (Pro-Q 4) or just one classic passive EQ curve (Pultec Passive EQ Collection).

Where to buy

Acustica Audio: see store

Tutorials and reviews

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