I'm a big fan of M-Audio's desktop monitor speakers. Their build and sound quality standards, even for their near entry-level models, are exceptional. The new BX5 Carbon retails for $149.99 each.
The vinyl-wrapped, medium-density fiberboard speaker measures 10x7x8 inches. Around back there's a large bass port, so don't plan on placing this guy up against a wall. Each 11-pound speaker has two built-in amplifiers: a 40-watt unit for the 5-inch woven Kevlar woofer and a 30-watt for the 1-inch silk dome tweeter. Rather than use the more common Class D amps, M-audio engineers opted for Class A/B designs, which I prefer. I was surprised to see the BX5 Carbon lacks bass or treble tone controls, which are usually found on desktop speakers.
The rear panel hosts a volume control and XLR and TRS 1/4-inch input jacks, but no RCA jacks, a common omission on pro monitors. The workaround solution is easy enough: I bought a set of 1-meter RCA-to-1/4-inch plug cables on Amazon for $6.
The BX5 Carbon's sound is beautifully balanced and clear, definitely up to audiophile standards. Once I focused on the task at hand, I noted that some overly bright recordings sounded harsh, but the BX5 Carbon was just doing its job, telling it like it is. That is, after all, what monitor speakers are supposed to do. If you want a speaker that makes everything sound nice, don't buy a monitor. Check out Audioengine's A2+ speakers; they take the edge off nasty sounding MP3s.
I watched a few movies, including my old favorite, "House of Flying Daggers," and the BX5 Carbons projected a huge soundstage. The scale of the sound was remarkable, so I felt no need to add a subwoofer or surround speakers. Dialogue sound quality is crucial, and here again the BX5 Carbons didn't let me down. With movies and music you can control the speakers volume directly from your computer. I also listened to the BX5 Carbons as hi-fi speakers in my bedroom, hooked up to an Oppo Blu-ray player, and controlled the volume from the Oppo.
I didn't have the M-Audio BX5 D2 monitors ($299/pair) on hand to do a direct comparison, but I think the BX5 Carbons have more oomph, while the 'D2 was a little clearer. They're different, but I'm happier with the BX5 Carbons' sound.
I did a BX5 Carbon/Emotiva airmotiv 4 ($349/pair) speaker face-off. The 4s are richer sounding, but the main difference is the treble -- the airmotiv 4 is more refined. There's a delicacy to the airmotiv 4's sound I really love, but the BX5 Carbons are more revealing and analytical speakers. You hear more deeply into the mix with the BX5 Carbons. They're both stellar monitors -- there's no clear winner here.