How do underpowered speakers sound?

JamesP1701

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Hi all,

Before I bought my new anthem 310 had a lot of conversations with people as to whether it would power my B & W 683 fronts, him 62 centre and ds3 rears. Now that I have it, it sounds wonderful but I can't help being curious as to how I would even know if they weren't receiving enough power.
 
If the amp lacks the power to drive speakers to a desired volume level then you tend to overdrive the amp while trying to attain those levels which more often than not results in clipping.

You'd hear distortion and in some instances, parts of the audio cut off and entirely replaced by nothing but distortion.

It isn't a matter of speakers not getting enough power, it is a matter of an amp having to work harder to supply them with power. Any amp will struggle with any speakers depending upon the desired volume level in relation to the primary listening location.
 
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When you play louder it won't sound compressed and harsh. In my experience 4 ohm speakers and AV amps don't play together well, sounds all mushy and lumpy on the bass.

I've long gone moved away from AV amps for the main system.

logyc has anthem and ati 6005 so probably ideal to hear from hin
 
The bass sounds fabulous! All really grand to me.

What does clilping sound like?
 
Distortion and anomalies with the harmonics.









 
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If the amp lacks the power to drive speakers to a desired volume level then you tend to overdrive the amp while trying to attain those levels which more often than not results in clipping.

You'd hear distortion and in some instances, parts of the audio cut off and entirely replaced by nothing but distortion.

It isn't a matter of speakers not getting enough power, it is a matter of an amp having to work harder to supply them with power. Any amp will struggle with any speakers depending upon the desired volume level in relation to the primary listening location.
Actually, there will also be an audible effect prior to the onset of clipping, clipping representing total breakdown. Distortion increases with power output, so as the amp stretches towards its maximum power (prior to clipping), the quality of the sound will deteriorate as the distortion increases. Past a certain level, this will be clearly audible as a clear falsification of the original sound.

But to answer the OP's question: if you have to ask if you can hear it and what it sounds like, then you don't have it and you can stop worrying. If you are clipping or distorting heavily, you'll know it from your cringing. Also in the case of your Anthem 310 + B&W, if you're clipping you are well past what your ears were designed to be able to absorb without suffering serious damage, and you should turn the volume down to below the deafeningly loud level you have dialed up.
 
Actually, there will also be an audible effect prior to the onset of clipping, clipping representing total breakdown. Distortion increases with power output, so as the amp stretches towards its maximum power (prior to clipping), the quality of the sound will deteriorate as the distortion increases. Past a certain level, this will be clearly audible as a clear falsification of the original sound.

But to answer the OP's question: if you have to ask if you can hear it and what it sounds like, then you don't have it and you can stop worrying. If you are clipping or distorting heavily, you'll know it from your cringing. Also in the case of your Anthem 310 + B&W, if you're clipping you are well past what your ears were designed to be able to absorb without suffering serious damage, and you should turn the volume down to below the deafeningly loud level you have dialed up.

That's good to know. Thank you. I've been wondering whether the 310 can power my b&ws sufficiently. I listen at -25 occasionally going to -20.
 
That's good to know. Thank you. I've been wondering whether the 310 can power my b&ws sufficiently. I listen at -25 occasionally going to -20.
You should google the THX power specifications, just for some perspective. They test numerous movies realistically and determine some sort of a standard for power requirements. The real world power requirements for playing a movie with speakers down to 3 ohms is not large. I forget the actual figures but it is something like 50 watts into 8ohm. Obviously higher for 4ohm speakers. That is for playing movies at reference with headroom for peaks. The Anthem 710 puts out around 75 watts all channels driven into 8 ohms with low distortion and much more with higher distortion.

In the real world playing at that level too often you'll be deaf before Needing to worry about your amp cutting out or not being able to cope.
 
You should google the THX power specifications, just for some perspective. They test numerous movies realistically and determine some sort of a standard for power requirements. The real world power requirements for playing a movie with speakers down to 3 ohms is not large. I forget the actual figures but it is something like 50 watts into 8ohm. Obviously higher for 4ohm speakers. That is for playing movies at reference with headroom for peaks. The Anthem 710 puts out around 75 watts all channels driven into 8 ohms with low distortion and much more with higher distortion.

In the real world playing at that level too often you'll be deaf before Needing to worry about your amp cutting out or not being able to cope.
Is the upshot then that the worries about whether the 310 will power them is completely unnecessary?
 
Is the upshot then that the worries about whether the 310 will power them is completely unnecessary?
As long as you use the amp normally you should be fine from a power perspective. The concern is that the Anthem has an aggressive thermal protection policy to guard against damage. But if you follow the various threads on the net it affects very few people. With my 8ohm speakers I've never even heard the fan, let alone had a shutdown.
 
there are a couple of Audiolab x7's going they might not be the best amps around but certainly a step up from those in av amplifiers, and not bad value. Also if you're interested in atmos, a good way to get all the channels, for sensible price. Maybe use 7 for side/rears/ceiling (although that's 8) once you get a decent 3 for front three.

ie I had several two's so plenty of options, now sold two two's going from biamping front three, to just single channel, so went from 6 channels (three amps) down to 3 channels, and one amp. Bit more sensible. Got two two's for side/rears but could change to one four ch.

If you've got the cash to go power I'd recommend it, I wouldn't do it for a budget system but once you start aiming higher up..
 
the distortion we are talking about isn't immediately obvious. Especially with B&Ws where its more a matter if sudden impedence drops.

So for the most part its ok, then during a bass heavy passage or taxing material such as orchestral stuff, as stephen mentioned, bass becomes muddy and less defined. The mids and trebles also end up sounding a bit shrill. Not immediately obvious. Because things are loud, you just associated that jarring sound as due to the loudness. But its actually distortion due to clipping.

Might even make you think "wow that's exciting / super clear".

With B&W 600s, an amp struggling basically gives you the impression the sound is struggling. The speakers seem strained. Much more evident when going loud. Easy to think its a speaker problem.

I noticed many mainstream chains use simple jazz or chamber music to demo. Mainly solo instruments and voices. While that focused detail is useful, its really "busy" material, like movies, or orcehstral stuff that challenge a setup to resolve all these myriad tones and sounds coming through.

The other thing about an amp which just about coping is the sound seems stuck to the speaker. Like its trying to get out.

All this is hard to appreciate until you slap a power amp on and hear the difference for yourself.

For B&Ws especially, suddenly its smooth an mellow. Like James Bond sidling up to the bar; shaken not stirred.

the sound is projected and widened. Like you're in the thick of the action.

Bass is tight. Every note becomes better defined.

Most of all, you can go really loud without feeling uncomfortable.

At the main Anthem MRX thread ppl were talking about listening at -15. I can easily push my system to -9 in a tiny room without feeling getting a headache. I could go further but need to preserve my hearing!

The best way to find out, is to really listen to it yourself.

You're welcome to drop by.
 
That's really helpful and kind. I can't listen anywhere near to that; -25 is normal and at a push -20. To be honest, the speakers sound great. Would nevertheless be interested to hear how a power amp would change things.
 
West London, Acton.
 
Thank you for taking the time to write all this. Sadly that's going to be too fr for me to travel. However, what would be the type of thing I'd be looking for-bearing in mind I'm on a tight budget now!!
 
After hearing a demo of a £2000 av amplifier I decided then once I go to that point, I'd go pre power. That amplifier strained, at higher levels you could tell the amount of distortion. The speakers they were using were quite efficient easy to drive.

All my speakers are 4ohm too, and dip lower than that.
 
Really interesting.

I'm still wondering whether it is worth it for my listening levels: I'm never going to be able to go above -20 so is it just additional expense. I'm slightly overwhelmed by the vast array of (very helpful) views: some people think I need extra power, some say I don't!!

What I need I feel is to be able to try a power amp and see before I commit myself.

J
 
You could just get a 2 channel, one of my SX's isn't an expensive outlay. Also by having offboard for at least one stereo pair, your Anthem has more power for the remaning channels.

So an external 60W may on paper be the same as the Anthem into 8ohm, but you'll get probably 20W per channel extra for others

"Five channels driven continuously into 8-ohm loads:
0.1% distortion at 71.4 watts
1% distortion at 83.4 watts

Seven channels driven continuously into 8-ohm loads:
0.1% distortion at 56.3 watts
1% distortion at 70.9 watts"

Granted yours is 310 so it's not 7 channel but it may be roughly the same. 20W isn't much but when you're only dealing with 60W....not like 20W on a 300W amp.
 
By that argument, you don't really need anything. But given your speaker setup, a power amp is a good investment.

I used to bang on about it and I think I need to go on a rant about it again.

A power amp is not about volume. Just like a car with a bigger engine. Its not necessarily to go faster. But makes the ride smoother, more responsive to changing conditions. Don't have to change gears so often and paradoxically can be even more economical.

the biggest day-to-day benefit I find with a power amp is that it actually allows me to listen at lower volumes!

Because the entire frequency is better amplified. I can hear the whole spectrum at overall lower volumes. Because it is less distorted, I don't have the urge to turn it up.

There are a couple of Audiolab 8200X7s on the classifieds. They're ok as a starting point. You can bridge 2 channels to up the power of the main channels if only driving 5 speakers.

Else some Rotels 1582 or 1552s will do for now. Also check out Emotiva. Shipped direct from the States, you can get the XPA3 (3 channel) for about £1k including shipping and duty, Pop a query at the Emotiva thread.
 

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