[Sonic Defender]

  1) There are some amps that begin to distort excessively near their upper power limits. If that power limit is too low for me, then I wouldn't buy that amp, however, most good amps do an excellent job as not to create any issues.
2) Our senses adapt. You ever walk into the house from outdoors and notice that incandesant lamps have a yellowish color balance that after a few minutes changes to normal? That's your vision adapting. Your vision adapts to brightness/darkness.And so does your perception of volume. Of course listening at excessively loud sounds can lower your perception of loudness by damaging your hearing so turning up the volume further is not a wise choice under such conditions. As far as headroom goes, if you increase the volume at one point getting past compression you would need additional headroom, however, I'm afraid that at one point that would be bad for the health of your hearing and well past comfortable listening.
3) As long as you don't exceed the maximum power rating of your speakers/headphones no damage can occur. So if you're underpowered by specs, nothing should happen. What situations did you read of that suggest such damage? Clipping can lead to more power by adding distortion to the ouput, however,the amp should not be able to produce more power than it is rated for, hence no problem.

I'll try to find the article I read about underpowered amps. Thanks for sharing your thoughts.

 

[money4me247]

  I'll reiterate for balance. IMO the need for power and scalling is overstated. 1W will drive the 560's to 120 dbSPL continuous loudness, ear spliting. That is more than most if not anyone will need for peaks. If your amp can do that for peaks, which any decent amp can do if rated for that power level, any more power above that will not be used and has nothing to contribute. If one wants to buy more power, it's available and they can.

I think you are right, but to be fair, people talking about scaling are also referring to the quality of the amplifier implementation and design, which may affect the sound quality.

 

[Koolpep]

I think you are right, but to be fair, people talking about scaling are also referring to the quality of the amplifier implementation and design, which may affect the sound quality.

Oh sure. That could be. Whenever I tried a more powerful amp it was most of the time as well a better quality one - so it could be coincidence that for me :more power - better sound quality. Maybe it was just: better amp - better sound quality. But then there are so many factors noise, voltage swing, output impedance, shielding, channel balance, etc etc. volume is most of the time the least of my worries to enjoy music. I tend to listen at very moderate levels most of the time.

Cheers,
K

 

[Koolpep]

1) There are some amps that begin to distort excessively near their upper power limits. If that power limit is too low for me, then I wouldn't buy that amp, however, most good amps do an excellent job as not to create any issues.
2) Our senses adapt. You ever walk into the house from outdoors and notice that incandesant lamps have a yellowish color balance that after a few minutes changes to normal? That's your vision adapting. Your vision adapts to brightness/darkness.And so does your perception of volume. Of course listening at excessively loud sounds can lower your perception of loudness by damaging your hearing so turning up the volume further is not a wise choice under such conditions. As far as headroom goes, if you increase the volume at one point getting past compression you would need additional headroom, however, I'm afraid that at one point that would be bad for the health of your hearing and well past comfortable listening.
3) As long as you don't exceed the maximum power rating of your speakers/headphones no damage can occur. So if you're underpowered by specs, nothing should happen. What situations did you read of that suggest such damage? Clipping can lead to more power by adding distortion to the ouput, however,the amp should not be able to produce more power than it is rated for, hence no problem.

Ad 2) I would specify that our senses don't adapt but how the data is interpreted by the brain. The eyes are sending the same information to the brain but the brain then compensates for the correct "white balance" for example so white things stay white even under different conditions when technically they are not white anymore. The eyes always see red as red but ask any eye witness and you get lots of varying answers as the brain (and memory) are playing their own music. Same with scents. We smell something and after a few minutes or so we can't smell it anymore. The scent is still there, our nose's receptors still receive it, but our brain decided we don't need to consciously smell it anymore as it considers it now "normal".

Same with hearing. I have headphone where depending on the amp the soundstage is rather large and defined so I can place instruments properly or smaller and blurred. What creates these spatial accuracy or not is not yet fully understood but a lot of companies are getting close to it. http://www.innerfidelity.com/content/dysonics-rappr-headphone-audio-virtualizer-and-rondomotion-head-tracker

Just yesterday I got my new K7XX and compared it to the HE-560 and I really liked how the HE-560 wraps the sound around me while the K7XX has a very large soundstage but further away and not as enveloping - for the lack of better words.....

 

[StanD]

  I've read your opinion on amps for a while now—just to be clear, are you saying that it's impossible to discern the difference in SQ from two properly designed amps at the same SPL? Or are you just saying that excess power isn't what accounts for the difference?

Both. If an amp doesn't deliver what it's supposed to and it's within the limits of human perception then I would expect one to hear the difference. If an amp is designed to color the sound where one can hear the difference, then again I would expect one to hear it. Quality transparent amps are just that, transparent. As I always say, power never used in a good quality amp has nothing to contribute. That's my opinion as both an EE and and avid listener.

 

[wmedrz]

If there's a tone at 1khz, and at the same time another tone at say 40khz, will the 1khz tone sound differently than if it was played by itself? 

 

[money4me247]

  Both. If an amp doesn't deliver what it's supposed to and it's within the limits of human perception then I would expect one to hear the difference. If an amp is designed to color the sound where one can hear the difference, then again I would expect one to hear it. Quality transparent amps are just that, transparent. As I always say, power never used in a good quality amp has nothing to contribute. That's my opinion as both an EE and and avid listener.

I am curious about what are some good sonic attributes to listen for when trying to determine if you have enough power (in you opinion).

 

[tretneo]

  I am curious about what are some good sonic attributes to listen for when trying to determine if you have enough power (in you opinion).

 
+1

 

[StanD]

  If there's a tone at 1khz, and at the same time another tone at say 40khz, will the 1khz tone sound differently than if it was played by itself? 

Firstly 40 kHz shouldn't be in your musical content as it is outside of the human auditory range. If the amp can process 40 kHz and it's level is high enough it is possible to overload the amp and get audible distortion.

 

[StanD]

  I am curious about what are some good sonic attributes to listen for when trying to determine if you have enough power (in you opinion).

Two things:

• Distortion at average listening levels. I'd be surprised if a quality amp has any of this.
• Transient distortion at peaks. This is something that you may have to listen carefully to hear, unless the amp is terrible. You will have to find music that has some measure of DR and turn up the volume some. There might be clipping or increased THD on peaks. Then there is TIMD (Transient Intermodulation Distortion).

 

[wmedrz]

  Firstly 40 kHz shouldn't be in your musical content as it is outside of the human auditory range. If the amp can process 40 kHz and it's level is high enough it is possible to overload the amp and get audible distortion.

Why not? Instruments don't produce any energy above the human auditory range?

 

[StanD]

  Why not? Instruments don't produce any energy above the human auditory range?

Can you hear it, No. Then why waste the power on it.

 

[Sonic Defender]

  Can you hear it, No. Then why waste the power on it.

Stan, here is something that as ignorant as it makes me sound I will ask. While we may not hear the 40hz signal, I'm wondering if there is any field relation to other frequencies. In my clumsy way I wonder if the complete signal for instance had 40hz waves, even if we can't hear them, would the waves being retained in their proper amplitude etc have any effect on other frequencies we can hear. Do they somehow effect each other so that one being missing, or poorly replicated will influence how adjacent frequencies are replicated? I haven't the faintest idea if this question is akin to asking if Unicorns prefer grapes over apples, but I thought I would ask.

 

[StanD]

 
Stan, here is something that as ignorant as it makes me sound I will ask. While we may not hear the 40hz signal, I'm wondering if there is any field relation to other frequencies. In my clumsy way I wonder if the complete signal for instance had 40hz waves, even if we can't hear them, would the waves being retained in their proper amplitude etc have any effect on other frequencies we can hear. Do they somehow effect each other so that one being missing, or poorly replicated will influence how adjacent frequencies are replicated? I haven't the faintest idea if this question is akin to asking if Unicorns prefer grapes over apples, but I thought I would ask.

First that was 40 kHz not 40 Hz. 40 kHz has nothing to do with us humans. In fact according it cannot be recorded on a CD due to the sample rate and Nyquist theory. So I wouldn't be concerned with the ultrasonic stuff.

 

[wmedrz]

I guess I'm being combative with you, but I think it all has to do with how our brain perceives the entirety of what we hear. We may not hear a single tone at a specific frequency, but IMO those frequencies have to do with how we interpret things like stage, imaging, dynamics, timing, detail, tonal balance etc...
 
And no I don't have any studies to back this up (maybe there are some?) but I also don't think experiments on how one "hears" a certain sound are indicative of any real world experience. They are however indicative of that particular test environment, which in turn is a bias onto itself. 
 
A true "double blind" study to me would be sitting at home on my recliner without any knowledge that I'm being guinea pigged. And there are those times where I say, "hey wait a minute, is this the CD verison?" lo and behold...
 
Edit: I'm being a little too harsh in saying "any" real world experience. Sure we can draw correlations etc. But it ain't the boiling point of water (then again, where am I going to find a perfectly straight line in the natural world?). Theory needs application. 
 
Edit 2: Maybe not CD, but there is plenty of data above the human auditory range on highly sampled material....