Q: Should I use an AVR or separate components? Here’s my current setup:
Anthem MRX 520 AVR (100 W/ch)
Vandersteen 2Ce Signature speakers
SVS SB12-Plus subwoofer
The AVR replaced a McCormack DNA-0.5 amp (100 W/ch) that was paired with a Promitheus Audio TVC preamp. I purchased the AVR mostly for the purpose of flexibility (I’m planning on adding at least a center channel) and convenience (running everything through the AVR).
Here are my questions:
1. It might be just my imagination, but the Anthem MRX 520 doesn’t seem as powerful as the McCormack, even though they’re rated at the same power. I can’t get it as loud without distortion (not that I play things loud), and the sound itself doesn’t seem to have as much depth. If an AVR and a separate amp are rated at the same output, is it usually the case that the amp will sound more powerful?
2. Would I gain much by using an external amp, such as the Outlaw Model 5000 (120 W/ch), with the AVR? Also, the Vandersteens’ recommended amplification is 40 to 160 watts per channel into 8 ohms. Can I go above 160 W/ch with an external amp and not damage the speakers? Again, I don’t play music or TV extremely loud; I’m just looking for more punch.
3. I have run ARC (Anthem Room Correction) in the MRX 520. It did help me place the speakers properly, but now that they’re where they supposedly should be, I’m not hearing much difference with ARC on or off. So I’m also wondering if I might be better off buying a less-expensive AVR with pre-outs and spending the money on an external amp.
– Dave Rosenbaum (davetroy)
A: I have not heard that a separate power amp generally sounds more powerful than an AVR rated for the same output. I suspect you’re hearing the difference in sound quality between these two particular amplifiers, with a possible influence from the Promitheus preamp. Not that the preamp provides extra power; it doesn’t. But it could be affecting the sound in some way that is different than what the Anthem AVR is doing in its preamp stage.
UPDATE: According to AVS Forum member akadoublej, the MRX 520’s power-output rating of 100 watts into 8 ohms is specified at 1% THD (total harmonic distortion) with only two channels driven, while the DNA-0.5’s power-output rating is spec’d at 0.05% THD. The Anthem website does not specify THD, while the DNA-0.5 manual specifies a THD of “less than 1%.” In any event, if the McCormack has significantly lower distortion at peak output than the Anthem, that could be why the McCormack sounds cleaner.
In my opinion, you wouldn’t gain much by using a separate power amp, other than a bit more power in the case of the Outlaw 5000. On the other hand, the Outlaw (or some other amp) could sound different than the McCormack or Anthem, and you might like it better than the other two—or not. That’s a matter of personal preference that can only be determined by actual listening.
Speaking of power, you bring up an interesting question about how much is too much. It’s actually a good idea to use a power amp with more than a speaker’s rated power handling—providing you don’t blast the speaker at full power. At normal listening levels, the vast majority of music and soundtrack playback uses a tiny fraction of that. Also, operating farther from the amp’s maximum power can result in cleaner sound with less distortion while providing more headroom for momentary peaks—that punch you’re looking for.
UPDATE: AVS Forum member akadoublej makes a good point about this in the comments. If you drive speakers with an amp that has too little power, it’s possible to push the amp into clipping, which can damage the speakers as you try to make the sound louder. If the speaker’s power handling and the amp’s power output are close to being equal, this shouldn’t be a problem. But if the amp is very underpowered with respect to the speaker’s power-handling capabilities, it could mean trouble.
I’m not sure how ARC helped you place your speakers properly. As far as I know, ARC compensates for acoustic anomalies in the room with the speakers in a given location. (Admittedly, I’ve never used ARC, so maybe it has a “speaker-placement optimization” function I’m not aware of.) I suppose it’s possible to move the speakers around to find the spot where ARC does as little processing as possible, but that’s a huge project. The goal would be exactly what you seem to have achieved—speaker locations that require little or no room correction.
If there’s little difference between ARC on and off, you don’t really need it, so you could get a less-expensive AVR and more expensive amp. But as you’ve seen with the two setups you’ve tried so far, the sound could well be different, and you might like it better—or not. Also, I hate spending money on an AVR only to use its pre-outs; the cost of the AVR’s power amps is wasted. That’s why I usually recommend getting a dedicated preamp/processor if you’re going to use external amps. On the other hand, a pre/pro is quite a bit more expensive than many AVRs, but I bet the sound quality will be better.
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