If you want some impressive sound from bookshelf speakers, team up Audioengine's (http://www.audioengineusa.com/) N22 Premium Desktop Audio Amplifier with their Audioengine P4 passives (AP4s).

The N22 is a compact integrated stereo power amplifier and headphone amp that you can connect to your iPod, computer, and speakers or headphones. Two audio inputs are standard so you can plug in your computer, iPod or stereo directly.

For example, you can connect it to your Mac or PC with no software to install or settings to change. You can pair the N22 amp with most speakers, but I did my test drive in tandem with the sweeeet Audioengine P4 passives. The result was impressive. And that was without a dedicated a subwoofer, which you can connect via the variable line output.

The vertical design of the N22 with its integrated stand allows the 22 watt/per channel stereo class A/B amplifiers to run cool through passive convection without a fan or heatsink. The N22 fits easily on your desk and doesn't take up much space.

For headphone enthusiasts the N22 includes a "high-performance, low-noise" discrete Burr- Brown/TI amplifier that works with all types of headphones and earphones.

The AP4 passive speakers are full-sounding bookshelf speakers in a satellite-sized package (they measure 9 x 5.5 x 6.5 inches). The folks at Audioengine say the goal with AP4 was to design a small but powerful bookshelf speaker for people that already have surround receivers or amplifiers and are looking for the same Audioengine sound and quality in a passive loudspeaker. They succeeded.

The N22/AP4 combo pumps out plenty of volume (though if you push it too high the treble gets a bit harsh) and some solid bass. Sound on both music and movies is crisp, clean and vibrant. I mainly used them on my Mac, putting them through their paces by cranking up the new (and excellent) Elton John-Leon Russell album, "The Union," and "Iron Man 2." The Audioengine package was good with both, but it really excelled at music, offering vocal performances that sound warm and distinct.

Also, I gave the N22/AP4 combo a run as satellite surround speakers in my home theater setup. They worked impressively and the audio quality was vibrant and clean when, for instance, watching "Avatar" on a Blu-ray player.

The AP4 passive speakers are designed for use with digital hybrid amplifiers (Class-D, Class-T, etc.) as well as most stereo receivers, integrated amps, and tube amplifiers. The AP4 has a 4 ohm impedance rating but will sound great when connected to almost any receiver or power amp with 4, 6 or 8 ohm speaker output impedance. By the way, the AP4s can be mounted on a wall using the integrated threaded inserts which are compatible with most wall or ceiling mount bracket systems.

The AP4 comes in satin-finished black or gloss white paint for $249 a pair, or in bamboo for $325 a pair. I was using the black model.

The Audioengine N22 Premium Desktop Amplifier retails for US$199 and the companion P4 Passive Speakers start at $249 per pair. Both are available from an authorized Audioengine reseller or online direct from http://www.audioengineusa.com .

If you really want to "high end" your system, get the Audioengine W1, a $99 wireless audio adapter that lets you play your music wirelessly from your Mac, iPod/iPad/iPhone dock or any other audio device to a powered speakers, stereo system or headphones.

The AW1 consists of two parts: the "Sender" and "Receiver." The former transmits audio from, for example, your computer through USB audio or from any product with 3.5mm mini-jack or RCA audio outputs. The other side of AW1, the Receiver, connects audio to any product with mini-jack or RCA audio connectors. Power for the Sender and Receiver is provided from either an USB computer port, from the included USB AC power adapter, or from any other USB AC charger (such as an iPod charger).

Each Sender/Receiver AW1 pair transmits uncompressed stereo audio. They can handle streaming lossless audio file formats such as Apple Lossless. Both wireless adapters transmit any audio file format with no compression or loss.

The AW1 is natively compatible with Mac OS X and Windows Vista/XP/2000. There are no drivers or software to install. And the wireless Audioengine set-up sounds very good. The receiver source sounded perhaps a bit more "tinny" then than the original source when it was "wired," but, overall, there's very little degradation of quality.

Also, you should note that you’ll need powered speakers or a stereo system to use the AW1. You can't take just any pair of speakers and have wireless music.

The Audioengine package comes the closest of any sound system I've tested to making me consider giving up my beloved Bose Companion 5 speakers. On the other hand, if you added a subwoofer to the N22, I'd predict Audioengine solution would edge pass the Bose in overall audio quality. What's more, iPod fans will appreciate the USB port for iPods and iPads.

Rating: 9 out of 10

-- Dennis Sellers