Aphex Systems

When it’s time to find your voice, find a 230. Good quality preamplification, compression, and frequency shaping are fundamental components for transforming an unruly vocal performance into something full of character, definitive, and, most importantly from the engineer’s standpoint, controlled. And transforming unruly vocal performances is where the Aphex Master Voice Channel 230 becomes relevant, as it provides more working solutions than nearly any other vocal box in its class.


The single rack space Master Voice Channel 230 is a complete voice processing system, including a low-noise RPA Tube Preamp, polarity inversion, phase rotation, Easyrider compression, Logic Assisted Gate, split band de-esser, high-resolution A/D converters, low distortion EQ, and Big Bottom and Aural Exciter features. You’ll also find phantom power, low cut, 20dB pad, effects loop, and a handy quick mute “cough” switch.

The low noise RPA Tube Preamp tunes 50dB on the dial in addition to 20dB fixed gain. In combination with the pad, the results range from pristinely transparent to fat and overdriven. Applying the phase rotator, a standout feature, significantly unifies speech symmetry. The meters have a toggle button between peak output levels and gain reduction levels from the compressor.

The compressor has only two controls, the gate has only two and the de-esser only one, which is great if you share the same logic as the engineers at Aphex and are not inclined to break any rules. While smart technologies in general are extremely valuable for working environments that must adapt quickly to different voice types, serious knob twiddlers may find themselves disappointed at the loss of control.

For those unfamiliar with Aphex products, frequency shaping with the 230 has a brief learning curve. What might be just parametric EQ is divided into Aphex trademark technologies Big Bottom and Aural Exciter. Big Bottom frequency ranges from 80–300Hz, and its intent is simple: Make the bottom bigger without increasing peaks. Aural Exciter frequency ranges from 600Hz–6kHz, and contributes a noticeable high-end coloration (as well as hiss when overused). Both Big Bottom and Aural Exciter have frequency tune dials and mix level controls. Sandwiched in between is a parametric EQ spanning 240Hz–4.5kHz. The parametric EQ has frequency, Q, and gain controls, and a totally neutral sound. The combination of these three features allows tremendous control over tonal coloration.

Another noteworthy feature is highly adaptable digital connectivity, so it integrates easily into many working environments. The 230 has base sample rates of 44.1 and 48kHz, and a multiply X2 function that brings the max sample rate to 96kHz. Digital outs include AES, S/PDIF, TOSLINK optical, and word clock I/O with internal and external source options.


I first delved into the 230 by plugging in a Neumann TLM 170 into the Master Voice Channel, lining out analog to an Mbox 2, then recording soprano vocals to both Pro Tools and Ableton Live 5. I systematically ran through each 230 feature, dialing hard and subversively, to which I found that I could make the gate thresholds extremely unforgiving — a creative application that renders harshly squared waves and unattractive noises akin to a barking seal. The 230 makes it very obvious if settings need adjustment, so if your performance is critical, and you intend to use gates and compression, I recommend being thorough in checking for the performance’s full dynamic range. I repeated these processes with the digital outs, and heard no significant difference between those and the analog outputs.

I also brought the 230 into the live realm, where I generally use a Joe Meek VC3 — a compact unit, full of character but nonetheless trustworthy. I performed voice captures into Ableton Live 5, with the path being a Shure SM58 to the Aphex 230, analog out to the Mbox2, receiving through DigiCore Audio, and into Ableton 5. Applying significant preamplification, compression, gate, parametric EQ, and Aural Exciter, the end results were incredibly positive, adding to both the cut and the body of the vocal, much as it did in the studio.


The Master Voice Channel 230 is both versatile and compact, offering complete voice solutions for almost any working environment — particularly those that need to quickly adapt to different voice types — making the unit at home in the studio, but also equally useful for live performance and broadcast.

Any control lost with the Logic Assisted gate and Easyrider compression is gained in frequency shaping with the parametric EQ, Big Bottom, and Aural Exciter. The Aphex exclusive SPR Spectral Phase Rotator packs a most understated wallop, magically shepherding all runaway transients into the corral, and increasing overall signal density; this feature alone is worth the price of admission.