How much better is an external amp (1 Viewer)

[Andrew W]

So I've currently got a Sony STRV444ES that claims to give me 120W x 5 channels at 8 Ohms. When I use it to run my new Rocket 850's/RSC/250's I get enough volume to be "too loud" before the 444 is cranked all the way up. In fact, it usually shows the volume to be -20dB through -40dB depending on the input source listening at "good loud" levels. (volume on this unit runs from -99dB up to 0)

But, I know more power is better and I'm considering a 5x200W external amp like a Rotel 1095 or Outlaw 7500.

So my question is what can I expect as far as sound quality if I go to a more powerful external amplifier? I think 200W would be great, but could I also get along with something only slightly more powerful like 125W per channel and would it sound any better than what I have in the 444ES?

Thanks,
Andy

 

[Steve^S]

In your post you refer to power and that, in my opinion, is not the determining factor.
All I can give is my very limited experience. Had a Denon receiver with 110wpc x 5. Bought a Bryston 110 wpc 2 channel amp to drive my front mains for music. The amp was delivered at work. When I got home wife was in the kitchen and had a cd playing. Stopped the cd and hooked up the amp through the preouts, turned it back on. Wife yelled from the kitchen "what did you do to the stereo, it sounds great". Point of the story is it's not the power but the quality of that power.
You can expect cleaner, more detailed, fuller sound than you have through your receiver. This was my experience, your mileage may vary.
Steve

 

[JohnRice]

Plus, a better amp has nothing to do with where the volume control is. That is gain, which doesn't usually mean much. Of course, the volume level you usually use could be an indication that you have pretty sensitive speakers or don't really run them that hard. In the end, you may gain more with a good or better sub. I seriously doubt you really need a 5 channel amp. 3 channels should do fine, just to run the front. Let the receiver run the surrounds.

 

[Andrew W]

OK, so a 125W per channel may be fine if that's enough wattage to sound loud enough already?

If I don't already have the receiver at full gain, do I need to worry about clipping?

 

[JohnRice]

Andrew, you just need to get beyond the idea that power has anything to do with where the volume knob is turned. A good way to look at it is that "too loud" usually comes from one or both of two things. Too little power or overdriving the speakers. If the amp is being overdriven, you will get distortion and it will be unpleasant. More power will let you play the same volume (I'm not talking the same point on the volume dial, but the same sound pressure level) without distortion and becoming unpleasant. Now, if the distortion is due to the speakers reaching their max, there is nothing to do other than get better speakers.

Also, power ratings are almost meaningless. It is a lot more difficult to determine who much raw power an amp has.

 

[Brent_S]

Output power is a result of both the input signal level and your gain setting. Think of it like the volume difference between commercials and the actual show you're watching on TV. You didn't touch the volume (gain) but the commercial was recorded at a higher level than the show's soundtrack, creating a higher input signal to the amp and thereby producing more SPL at the same gain setting.

You could clip your amp at 25% gain with the right input signal or you could turn the gain to 100% and never clip. The relative position of the volume knob is virtually meaningless with regard to output power.

I think you missed John's point. If you're not hearing any negative qualities with your receiver now, you're not likely to notice a difference with a separate amp, more power or not...unless you convince yourself there will be a difference. A separate amp will likely have a measurably lower noise floor, better channel separation, and more dynamic range, but unless you're pushing the receiver amps beyond their specified limits, the real world audibility of this difference is swamped by the difference between speakers/subs or room treatments. Without attempting a level matched blind test, any differences you hear could just as easily be expected perception instead of real differences. IMHO.

With that said, I've read that most receivers use up a majority of their gain within the first 25%-50% of volume adjustment. Marketing 101 says the consumer will perceive the unit that gets loud faster (with less knob twisting) as being more powerful and better sounding. If this is true for your Sony, you may be on the ragged edge of your amps as your using 60-80% of your available adjustment.

Only way to know for sure it to try. If we tell you what to expect, you'll probably hear the difference in proportion to how much money you spend.

-Brent

 

[Andrew W]

Well, I know there is a difference in sound quality even between equally rated receivers. When my 444ES was in the shop we borrowed a different 5x120W receiver and it sounded like mud. At first, my wife didn't know it was a borrowed receiver and thought they had "broken" ours. (roughly same volume levels because I had already done its self calibration at 75dB.)

 

[Brent_S]

There's no defined standard for rating multi-channel receiver output so two different 5x120 "rated" receivers could have vastly different real world output levels. Was the difference present at low volume or only high volume?

Notice, I never said that amps can't sound different. Only that if you're happy with the Sony now, you're not likely to notice a difference with an external amp in an objective comparison. Once you spend the money and know which unit you're listening to, most objectivity is thrown out the window.

-Brent

 

[Andrew W]

The sound difference was very apparent at mid to med-high comfortable listening levels. Just muddy and ughh sounding.

That's why I like to test stuff on my wife. She's got a good ear, but has no idea what I'm tinkering with, so I can A/B test on her and get honest feedback.

 

[JohnRice]

It is unlikely the amps in two different receivers made that much difference. Other factors were mose likely responsible. Self calibration is a likely suspect. That feature is known to do all sorts of strange things.

 

[Brent_S]

Good point, John. When you swap receivers, you're comparing the whole receiver...decoder chips, preamp section, BM, DACs, etc...not just the amps.

-Brent