It has been a while since Pioneer last made serious two-channel audio components, and it's perhaps a reflection of how crowded things have got in the AV market that it has decided to have another stab at it now.

Unlike some of its rivals, Pioneer does have some pedigree in the two-channel arena; it made some decent CD players and integrated amps in the nineties and a very fine turntable in the seventies. Among the amps was a giant-slayer, the legendary A400, and it's this model that's said to have inspired the new the A-A9.

The A400 was particularly popular with reviewers, because despite being an entry-level amplifier, it worked rather well in higher-end systems.

It delivered in more down-to-earth systems too, and the the rave reviews produced big sales figures for Pioneer. For the A-A9 and its more affordable sibling, the A-A6, the company got hold of an A400 to use as a point of reference at the tuning stage.

This was done at AIR Studios, George Martin's recording facility in Hampstead. Pioneer used this facility for its VSA-AX10 AV behemoth a few years back, and must have a sponsorship arrangement with the place, given how often its engineers seem to visit.

The A-A9 differs quite considerably from the A-A6. The output power is higher for starters - albeit only by 10 watts - and, more importantly, it has toroidal rather than standard mains transformers, aluminium side and front panels, a motorised volume control, MC as well as MM phono input and a USB input (on a B-type socket) for PCs and MP3 players.

There's also a Sound Retriever function designed to improve the sound of such compressed audio sources, and "professional, big, gold-plated, screw-type" speaker terminals (this is perhaps overselling them, but they are rather better than those on the smaller amp).

Volume control

The volume control is a proper motorised Alps potentiometer rather than the continual-rotation type found on the A6, but it only has a small indent to indicate the level. The display shows this numerically, but the amp's 'direct' setting means that the backlight is normally off. In other words, you can't see how loud it will play at a glance.

The sculpted front fascia is attractive and has the minimum of controls, most facilities being accessible via the remote: a very slim affair with the volume buttons a little too close to the off button.

The display, a backlit LCD type, can be dimmed and stays on in standard mode, but in the 'direct' mode, which bypasses the tone and balance controls, it only illuminates when you change level or input, so you can't tell which input is selected without pressing a button.

The A-A9 partners well with Tannoy's Glenair 10 loudspeaker, a model whose openness and dynamics make the most of the amp's precise and subtle sound.

In some respects the Pioneer is a bit too tonally lean for the Tannoy, but it does a fine job of revealing its speed and definition. That said, we tried it after experiencing the smooth Sugden A21aL Series 2, clearly a more relaxed-sounding amp that doesn't have the bold muscularity the Pioneer can produce due to its higher power.

Further listening reveals that the A-A9 is more than able to extract high levels of detail in a transparent and three-dimensional fashion.

A slightly more appropriate comparison is with Cambridge's popular Azur 840A , which costs £150 more and offers another 30 watts. In the studio this translates to significantly greater bass extension and power; we were quite surprised at how much extra grip the 840A managed to deliver.