Hardware vs Software: Aphex Aural Exciter

In its physical form, or as a plug-in, the Aphex Aural Exciter is still an in-demand, highly regarded piece of music technology. John Pickford explains why…

Aphex appeared on the recording scene in 1975 with the first incarnation of the Aural Exciter. Designed to add clarity and sparkle to lifeless recordings, the unit created a buzz within the recording industry at the time, particularly in Los Angeles, where many of the most highly regarded studios in the world were situated.

One of the first successful albums to make use of the Aural Exciter was Fleetwood Mac’s Rumours, which was recorded at The Record Plant in California in 1976. The lengthy overdubbing process had a negative impact on the condition of the 24-track master tape, so by the time the project had reached the mixing stage, the worn tape had rendered many of the sounds dull and flat. This is where an enhancer such as the Aural Exciter came in to its own, restoring some life and top-end sheen to the tired sounds.

Although the Aphex Aural Exciter could be regarded as a type of equaliser, it operates in a very different way from conventional EQ systems. The Exciter enhances audio by adding synthesised harmonics to the existing high frequencies of the signal by way of Aphex’s patented ‘Transient Discriminate Harmonics Generator’. During this process, a certain amount of phase shift occurs, which adds to the final effect.

The unit can be tuned to improve presence and intelligibility, as well as creating a sense of air and space at higher settings. Unlike standard equalisers, this process of boosting perceived high frequencies does not alter level or produce the unwanted effect of increasing hiss, a problem often encountered with top-end boost, especially when mixing from analogue tape. 

Originally, the Aural Exciter was available only to hire, however its popularity led to the release of the lower-cost solid-state Type B and Type C models, which were available to buy. In the 1980s, no respectable recording studio would be without an Aural Exciter and, much like the SSL mixing console that came later, owning one could be the deciding factor in an artist’s decision to use your studio; some went as far as boasting of its use in their albums’ liner notes.

1992 saw the addition of the Big Bottom circuit to the Aural Exciter, which, as you might imagine, provides similar enhancement but to the low-end.

The Aural Exciter’s patented technology is available nowadays in both hardware and software formats. Aphex currently offer a 2 channel Exciter as a 1u 19” rackmount unit, while versions in 500-series ‘lunchbox’ format and even foot-pedals have been produced.

Waves offer a brilliant plug-in version developed in association with Aphex, which is modelled on an original valve powered unit, of which only a few were ever built. This software version sounds superb and is arguably better than many of the hardware versions produced over the past 40 odd years. That is unless you can get your hands on one of the rare-as-hens-teeth thermionic units.