MusicRadar

A powerful source of sonic manipulation options.

1 of 2 » View in gallery

• Review

IRCAM Tools is a new range of plug-ins covering positional room acoustics simulation (Spat), more straight-up reverberation (Verb) and real-time audio manipulation (TRAX).

Here we're focusing on TRAX, which is shorthand for transformation and cross-synthesis and comprises three plug-ins: Transformer, Cross Synthesis and Source Filter. Each uses IRCAM's Super VP phase vocoder technology.

Pitch perfect

Of the three plug-ins, Transformer is not only the most complex and feature-rich but also the most recognisable in its aims. You'll find Source and Target controls: the parameters of the former are dialled in according to the characteristics of the input signal, while the latter are used to set the pitch, formant and timbre characteristics of the resulting output.

There are three processing modes: voice, instrument and music. These affect not only how the results sound, but also the options available.

"The mixer is enlightening, letting you balance pitched, non-pitched and transient components."

The music setting only offers pitch and formant adjustment, whereas 'voice' mode includes six gender/age presets for source and target, and eight register presets (eg, soprano, tenor and bass) for shifting pitch. Advanced features include the Voice Forger, which enables you to correct the tuning of (ie, autotune) your original signal to fit a scale.

Common to all three modes are two octaves (up or down) of pitch and formant shifting, LFO modulation of pitch and formant (not tempo syncable, unfortunately), spectral envelope, the output mixer, oversampling (x1 and x2), high and low-pass filters and a dry/wet control.

The mixer is particularly enlightening, letting you balance the pitched (Sinus), non-pitched (Noise) and transient (Trans) components of the signal. Also rather smart is the spectral envelope, which you can use to redistribute frequency content.

Finally, Transformer lets you store two complete patches, A and B, and morph between them using the crossfader.

Cracking the vocode

The other two plug-ins - Cross Synthesis and Source Filter - have more straightforward controls. Both take in two independent mono signals, producing a single output (ie, duplicated in the left and right channels).

Cross Synthesis is the simpler of the two, using the amplitude and frequency spectra of both source signals to determine the output signal. The primary controls are Amplitude and Frequency sliders, enabling you to control the influence of each source. Controls can be linked in inverse fashion.

The Source Filter is similar to a vocoder, with the left input being the source or 'excitation' signal, and the right input dictating the filter. Additionally, there are 'temporal envelopes' that determine the influence each source's dynamics has on the output.

Look a little closer

Both the Cross Synthesis and Source Filter plug-ins are available in stereo only, whereby you have two inputs (left and right) and one combined stereo output.