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speaker efficiency, more than volume level?

invaderzim

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If I have a low powered amp (10 watt or so) and speakers that are only 88dB for the efficiency am I losing anything in sound quality at lower listening levels?

I read and hear over and over that if you have a lower power amp you need high efficiency speakers but if I never get anywhere near the volume level for distortion out of the amp and am plenty happy with the sound level am I missing anything?
 

restorer-john

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If the levels are sufficient for you, and the type of music you play doesn't have dynamics that push your amplifier into overload, then be happy with it.

Not everyone needs, or wants, realistic concert hall levels in their house. Anyone can do loud, it takes special speakers to do low levels well.
 

March Audio

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If I have a low powered amp (10 watt or so) and speakers that are only 88dB for the efficiency am I losing anything in sound quality at lower listening levels?

I read and hear over and over that if you have a lower power amp you need high efficiency speakers but if I never get anywhere near the volume level for distortion out of the amp and am plenty happy with the sound level am I missing anything?

So a speaker pair with that sensetivity and power will hit about 100dB. If that's loud enough for you then no problem. Power doesn't equal audio quality per se, but can be useful if your speakers are a very difficult load
 

PierreV

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Nothing if you are happy.

If you are listening at 1 meter from your speakers, you need 1 watt to produce 88dB which should be enough to match the level of a typical jazz concert. Roughly speaking if you move away from the speaker or want to increase the volume by 3dB, you'll need to double the power to 2 watts and so on. Rule of thumb - the feeling may vary depending on the room size.

That's why you'll see, even in the high end, people be just as happy with 25 watts amplifiers than they are with 250 watts.

What's probably more important is the stability of the amplifier combined with the speakers they are driving, the ability to deliver current when the impedance falls.

Take a look at that one for example, from a well known amplifier designer

https://www.stereophile.com/content/pass-laboratories-xa25-power-amplifier-specifications

Based on 8 Ohms spec, it looks like a very bad deal compared to a cheap 2x50 watts per channel standard amplifier. When you did a bit deeper, you notice it will sustain a comparatively huge current draw at low impedance. Whether that matters depends on your speakers, probably not that much in most standard cases.

The nominal impedance of your speakers is only marginally useful information btw. See this for example for how low a 8 Ohms rated speaker can go

https://www.stereophile.com/content/focal-kanta-no2-loudspeaker-measurements
 

bigx5murf

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I used to have a collection of bookshelf speakers, with a big range in sensitivity. I was powering them with an old 20wpc kenwood. They all got loud enough for me with the Kenwood powering them. But the less efficient ones (sealed design). When I finally gave them more power (125wpc technics new class A), I noticed they had significantly more bass at the same volume I was playing them
 
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Sal1950

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If I have a low powered amp (10 watt or so) and speakers that are only 88dB for the efficiency am I losing anything in sound quality at lower listening levels?

I read and hear over and over that if you have a lower power amp you need high efficiency speakers but if I never get anywhere near the volume level for distortion out of the amp and am plenty happy with the sound level am I missing anything?
Everything the guys have already said here is true but there may be a bit more to the story.
It does all really depend on a number of factors we don't know here.
How loud are your "lower listening levels"?
What type of amplifier (SS, Tube SE, Push/Pull. Triode, UL?) are you using and what are it's distortion characteristics?
What is the input impedance of your speakers, output of the amp, when does the amp's distortion become critical when these details are factored in?
I'm not expecting you to answer these questions, just pointing out that the answer to your question is a bit more complicated.
My honest opinion, unless all your listening is done at VERY low levels, your really walking on the ragged edge, if not crossing it, of this amplifier-speaker capabilities and I would be much more comfortable with at least 50-60 wpc.
But without measurements it's really hard for anyone to predict.
 

Wombat

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Transients/impulses may not be reproduced properly without enough power. This may not be apparent if you are not used to hearing them.
 
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invaderzim

invaderzim

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The dB meter app on my phone shows a peak level of about 70 for the top range of my daily listening. I have cranked it to clearly audible distortion levels in the past but that isn't a frequent thing; especially with the little guy in the picture at the left not liking super loud things (along with my wife).
It is a Single Ende Tube Amp with 8 ohm output into B&W CM5 speakers rated at 8 ohm and 88 dB.

I've been playing with a 40 watt chip amp and definitely get more bass out of it but with the tube amp hooked into a subwoofer that seems to fill in pretty well there.
 

Sal1950

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I've been playing with a 40 watt chip amp and definitely get more bass out of it but with the tube amp hooked into a subwoofer that seems to fill in pretty well there.
You never mentioned anything about a subwoofer or how it is integrated into your system. ???
You've lost me ???
 

Ron Texas

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In small rooms high spl's can be reached without a lot of power.
 

tomelex

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In general, speakers that require least power and have the smoothest impedance are your best bet. There is low level information in the first watt of power that is lost in less efficient speakers. Never the less, if you are not hearing peak clipping with your tube amp then for now its not important. However, if you put a scope on the output of your amp, and you see clipping or for your tube amp evidence of rounding of peaks then you need more power or speakers, the caveat is if you cant hear it, it does not matter anyway.
 
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invaderzim

invaderzim

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You never mentioned anything about a subwoofer or how it is integrated into your system. ???
You've lost me ???

Sorry, it is easy to forget things. I hadn't thought about it until I had to shut it off with the chip amp this morning because there was too much bass then.

I should also mention the 70 dB was at 10 feet from the speakers, centered between them.

The sub is an 8" with speaker level inputs from this amp
 
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