A9

Pioneer's recent release of several higher end audio products, geared specifically towards two-channel audio, may seem a little surprising in this current age of 5.1 and 7.1 surround sound. Nevertheless, there is a certain appeal in the simplicity of stereo audio, especially for music, which often doesn't benefit a lot from surround sound setups. The A9 amplifier is an analogue, two-channel unit, made to high specifications and focused on high-quality audio performance above all else. It's an expensive product, probably out of the reach of non-enthusiasts, but its performance and technical specifications are at a level that justifies the high asking price.

This amplifier is designed with one task in mind - to produce high quality, lossless audio. It does it well. Everything about the amp is geared towards the best audio quality possible. Its connections, the power supply and the front panel display are all minimal, helping to keep the focus on the audio and prevent unnecessary degradation. While using the amplifier in conjunction with Pioneer's PD-D6 CD player, another in the range of two-channel audio products, we did notice exceptional audio quality, with an incredibly clear and realistic sound, especially throughout the treble range. It should be noted, however, that the difference between a unit like this and a mid-range receiver is still minimal; something that many potential users won't be able to pick up on.

In terms of design, Pioneer has kept things simple. The largish, silver box sports a small LED screen on the front panel, along with a power switch, indicator lights, a headphone jack, and volume and input knobs. The back panel is a simple array of two-channel analogue RCA audio ports: six inputs and one output, a "control" connection that allows the A9 to be controlled by other Pioneer remotes, a USB port for connecting MP3 players, and connections for left and right speakers. This simplicity helps to remove unnecessary components and lets the amplifier focus on audio performance.

The A9 continues this trend of simplicity in its features, the most prominent of which is Direct listening. It switches off the front panel screen, balance and tone controls, and the Sound Retriever feature, to let the amplifier focus on producing the clearest audio signal possible. When using this feature, we did notice a distinct improvement in the sound, which became sharper and better defined. The Sound Retriever feature (which is disabled when Direct listening mode is set) works to restore the effects of audio compression on compressed files, adding in extra information that was removed during compression and helping to eliminate minor distortion and to create a more natural sound. While both of these features do improve sound quality, again the extent to which they do so is not likely to be noticeable by non-discerning ears.

The unit's controls, again, are quite simple. Bass and treble can each be adjusted to either plus or minus ten decibels, in increments of two, and tone balance can be adjusted to favour either the left or right speaker.

Overall, Pioneer's A9 amplifier is a very advanced audio device, geared specifically towards a small audience of analogue audio lovers. Its feature-set and highly specific focus, combined with its relatively high price, make it a product best suited to enthusiasts, however its quality is such that anyone looking for a high-end, analogue, two-channel amplifier will be more than satisfied.