Review: BT Phobos weaves a Deep Tapestry of Sound

Spawned from the mind of the electronic musician, BT, and brought into reality by the folks at Spitfire Audio, BT Phobos is a software synth offering an innovative take on sound design. A “Polyconvolution” synthesizer, BT Phobos offers a sonic depth especially useful for cinematic applications. Its unique architecture rewards an empirical approach towards patch construction, and a ton of presets are included (some by BT himself) to help get you started.

BT Phobos Features

  • 20 GB Audio Library with over 9,000 Sounds
  • Over 700 Presets by BT, Richard Devine, and Others
  • Innovative Polyconvolver Synth Engine
  • Intuitive User Interface
  • Rich Sound Quality suitable for Soundtrack and Esoteric Creations
  • Supports Most Popular Plugin Formats
  • Street Price of $299

If you are searching for a synth plugin suitable for both cinematic and experimental electronic explorations, BT Phobos is squarely in your wheelhouse. This is definitely one of the most impressive products in the software synthesizer market.

The Polyconvolution won’t be Televised

The heart of BT Phobos lies within its unique polyconvolver synth engine. Convolution is a mathematical concept used in digital image and audio processing; in the latter case, uses are found in creating virtual reverbs or combining a rhythmic impulse onto another sound. Phobos lets you perform these convolutions using a collection of BT’s own 9,000 sounds containing both tonal and loop-based samples. It’s pretty esoteric stuff.

BT Phobos Screenshot

BT Phobos in action in the studio. Photo by author.

As with its synth engine, BT Phobos sports an innovative interface with up to four “Source units” and three convolvers. You are able to load any of the included samples as either a Source unit or a convolver. An animated triangular section in the middle of the screen controls the impact of each convolver on an individual source unit.

Loop samples keep the same pitch no matter the MIDI note trigger. You can set a range of notes and the polyphony for the tonal samples at the bottom of the Phobos interface. The convolvers trigger a new impulse with each note, making them polyphonic. This functionality is why BT Phobos is considered to be a polyconvolution synthesizer. Additional tweaking of the sounds is possible using the envelopes and additional tonal controls for each Source unit and convolver.

If this all seems a bit confusing, simply explore the over 700 presets to get a feel for the extreme sonic possibilities. BT Phobos is a synth that rewards exploration combined with empirical analysis. The preset designers include BT himself, the ubiquitous Richard Devine, and other electronic music artists.

A Stunningly Rich Sound Quality

Needless to say, BT Phobos sounds incredible; able to conjure rich and detailed pads and rhythms suitable for a wide variety of electronic music applications. Expect your mix to be dominated, so consider any other synth overdubs wisely. This synth sounds HUGE!

All this sound quality requires some hefty computing horsepower – 8 GB of RAM is the minimum with16 GB recommended. You also need 40 GB of free hard drive space during installation and around 20 GB after the fact.

My only real complaint about the product is you can’t load your own samples. This feature added to the polyconvolution synth engine would be sweet.

If you are in the market for a state of the art synth plugin designed by one of the leading lights of electronic music, BT Phobos makes for a wise choice. It is especially useful for anyone into soundtrack work and sound design.


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