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| Axiom M60s pictured in custom finish Cherry Chestnut Semi-Gloss |
 "The Axiom M60 v2 performs so far above its price that it might be the best speaker bargain today for under $1000/pair. The M60 v2 will draw you into your most-loved music, electrify your listening room with its seemingly boundless dynamic range, and re-create music in so tangible and lifelike a way that you’ll probably find yourself spending more time listening to music than you did before. The Axiom M60 v2 delivers not just good sound, but great sound. It’s one of the best speaker values on the market today."
-- Philip Beaudette, GoodSound.com
GamePro Editor's Choice Winner:
"How does it perform? In a word: amazing."
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| Axiom Audiobyte computer speakers in custom metallic green finish. Amp is included; subwoofer optional. |
"The Audiobyte set delivers performance that you'd expect out of a truly high-end system; no surprise considering Axiom's been in the high-end audio market for a long time. The audio is crystal clear and we didn't have to turn up the volume much to get it to the point where people on the other side of the office were complaining about the racket. The subwoofer also provides a nice, deep bass response. All in all, the Audiobyte pumps out some amazing audio that really brought out the best in our music, games and movies."
Editor's Choice - Tae Kim, GamePro.com
How to Choose an AV Surround Receiver
by Alan Lofft
Present day surround sound AV receivers have a come a long way from the stereo era; in fact, in the ongoing proliferation of ever-higher quality multi-channel surround formats, simple stereo receivers have become fairly rare birds. For many of us who still recall the days when 2 channels was the most you could hope for, the move to 7.1-channel AV receivers is something of a mixed blessing. Multi-channel surround can sound wonderful, of course, but choosing and operating a 5.1 or 7.1-channel AV receiver is inherently more intricate than 2-channel operation.
Don’t get me wrong; I don’t advocate a return to stereo for the sake of simplicity. I’m a surround-sound enthusiast, whether for movie soundtracks, musical concerts, jazz, rock, or classical recordings. However, for consumers who don’t want to get involved with five to seven speakers plus a subwoofer, a simple stereo receiver is all they need. Two companies that make excellent stereo receivers with robust amplifiers that will drive even 4-ohm speakers like Axiom Audio's M80 floorstanding speakers without protest are Sherwood Newcastle and Harman/Kardon.
Command Central
That said, a “receiver” serves as a command center for either a basic audio system (a stereo receiver) or as an elaborate audio-video routing, switching, surround decoding and amplification center for a multi-source audio-video system (a 7.1 channel surround AV receiver). In both cases, the receiver will contain an AM-FM radio tuner (whether you want it or not) and either two internal amplifiers (stereo) or, most commonly, seven amplifiers, for 7.1-channel surround sound. Now that Dolby Digital 5.1 surround sound has become the standard for HDTV broadcasts and the vast majority of DVD and Blu-ray movie soundtracks, it makes sense to get an AV surround sound receiver, even if you just use it in stereo for a time. The increased realism of surround sound is very seductive, not just for movie watching but for all genres of music listening. It is, after all, the way we hear in real life, with sounds coming at us from every direction, and it makes acoustical sense to reproduce it that way. Moreover, a basic AV receiver costs little more than a stereo receiver and gets you a lot more versatility and listening options.
Although some new AV receivers have connections for internet radio surfing and many are XM/Sirius satellite radio ready, a canny shopper must still consider basic output power for a given room and listening taste before going on to the more exotic features. Herewith is my guide to some of the most important questions you need to address in finding an AV receiver that will meet your needs and budget.
Power Output
It’s a receiver’s first duty to amplify the weak incoming audio signals to a level where they’ll drive loudspeakers to clean, reasonably high volume levels in most typical living rooms or home theaters without audible distortion (the latter produces harsh, edgy sound). The first thing to look for is the receiver’s rated per-channel output power into an 8-ohm load. (Most domestic speakers are either 8 ohms or 6 ohms impedance, which are essentially identical for purposes of power output).
The biggest problem with the per-channel rating is that it is frequently only one channel driven, so that every added channel will reduce the per-channel output power e.g., “100 watts per channel” is actually 50 watts per channel with 2 channels driven and 14 watts per channel with 7 channels driven. This recent habit of taking the 100 watts per channel and multiplying it by 7 (“100 watts x 7”) to get the so-called “total power” is complete nonsense.
The laws regarding AV receiver power output specifications are ridiculously lenient, so much so that if the aforementioned rating standards were applied to Axiom’s A1400-8 multi-channel power amplifier, we could state its power output as “1400 watts x 8” or as having a “total power output” of 11,200 watts! How did we arrive at this? The A1400-8 will produce 1,400 watts into one channel at 2 ohms, with one channel driven, so 1400 x 8 channels gets you the absurd 11,200-watt “output.”
Keeping it Real
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| Axiom M80 Floorstanding Speakers in Maple Natural Wood Finish, powered by Sherwood 4-ohm compatible receiver. |
The only method to determine how much power an AV receiver truly generates is to separately measure the total watts produced by each channel, or to drive 5 channels simultaneously and measure the output of each. Some brands don’t weather that sort of stress and immediately shut down. Others manage it quite well, which points to a good, robust power supply section in the receiver. Bench tests of AV receivers by Sound&Vision magazine routinely do a 5-channels-driven test and, if you read the fine print in the test results or online, it will state how much power the receiver produces and whether or not the receiver shut down because of overheating or current limiting. In a perfect world, every manufacturer would state the power output of AV receivers with “all channels driven,” either five or seven, into 8-ohm loads, over the full musical range. The power output will often be significantly less than with one or two channels driven, but if you find all channels driven spec or measurement, take it as a positive sign of robust amplifier design. If you’re thinking about getting a pair of 4-ohm rated speakers like Axiom’s M80 v2s for your front main channels, check the same Sound&Vision test reports for the AV receiver’s output results into 4-ohm loads. Some brands will not drive 4-ohm speakers without overheating or shutting down. Others, such as Sherwood Newcastle, Denon, NAD, Harman/Kardon and Rotel, have no trouble with 4-ohm impedances.
Look for the continuous power output with two channels driven into an 8-ohm load, over the full audio range of 20 Hz to 20 kHz (more often you’ll see the power output rated at a single frequency, 1 kHz) with total harmonic distortion (THD) of less than 1%, ideally 0.7% or lower. Distortion at that level is generally conceded to be inaudible with musical programming or soundtracks. Keep a close eye on the THD (distortion) ratings. Some manufacturers play fast and loose with power ratings, even specifying some packaged home theater in a box (HTIB) electronics at distortion levels as high as 10%, which will not only be audible but downright nasty sounding.
How Much Power Is Enough?
To cover all but very large rooms and extremely high-volume playback, most people will be quite happy with AV receivers rated at between 70 and 130 watts per channel, with two channels driven. Although many AV receivers will deliver far less than that when all channels are driven simultaneously, it’s not a severe drawback. Even with the most raucous movie soundtracks, it would be extremely rare to ever find an AV receiver having to produce simultaneous output of 70 watts or 100 watts into each of its 5 or 7 channels. Typically, the surround channels demand far less power output (a few watts) than do the main left, center, and right channels, which carry the bulk of the acoustical output demands.
Read the rest of the Receiver Buying Guide here.
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Q. I am going to purchase a pair of M22's, VP100, and EP350. I was planning to
use some cheap Logitech single full-range driver speakers for rears but I am
starting to be concerned as to how much this will degrade sound quality. I
know rear speakers add a great deal to the experience, but how important are
high-quality rear speakers? Do they need to present as much detail as the
front? I'm concerned with the single driver design of the Logitech's and
fear that they will not disperse higher frequencies well enough to create a
transparent rear fill. Would M2's make decent rear speakers or
should I look for something more omnidirectional? -- Andrew
A. The M2s would make excellent surround speakers if you and other listeners
are seated in the central listening area of the room, and the tonal match to
the M22s and VP100 would be excellent. I think you'd be thrilled with their
detail, whereas I think you'd be disappointed in the single driver Logitech
speakers as surrounds.
With some soundtrack surround and ambient effects, the detail can be
uncanny-- subtle sounds of rain, wind, storms, birds or, with music, the
reverberant nature of the hall or live recording location. The QS4 or QS8 quadpolar surrounds do deliver a greater sense of envelopment particularly
for listeners anywhere in the room than would the M2s, but if you are
sitting in the sweet spot area, the M2s will be excellent. In my judgement, there are no quadpolar surrounds of the same quality as the
QS4s or QS8s for less money. These are comparable to M&K bipole/dipole
models that sell for $1500 a pair. The M&Ks are excellent as well but are
costly. |
