Well, maybe nearly all audio equipment is broken to some degree. And some people are more sensitive to the "defects" than others, they do notice the effects ...
Of course that's the case, but if most manufacturers don't take them into account then it's up to the tweakers to do something about it ...
The headache is that the ears are capable of intelligently handling a big dynamic range; if they were only capable of the resolution of the eyes, say, then we probably wouldn't be having these arguments.
In other words, we hit the speakers with 10's of volts. And, next second with a millivolt or 2 of fine detail -- the ears can pick up that something is wrong there ...
Frank
No, I would only expect a moderator to participate within the rules, no personal attacks, etc.
That's pretty far from the truth. As one simple example the ability to "hear" one voice in a crowd is probably as computationally complex as seeing your kid almost immediately in a huge crowd.
At the end this is a forum about loudspeakers, so... I found a differentiator between a good and a bad woofer: if you exercise the woofer with a high-amplitude low-frequency signal (say 1 Hz to 5 Hz) just below Xmax, it produces a kind of nasty sound. A good woofer has no sound, its cone just moves in and out. I suppose this is a kind of distortion. Anyone has more information on this parameter, and how can it be measured?
I don't think that it is independent from the distortion in the operating range. If the woofer has bad non linearity / high harmonic distortion / high intermodulation distortion below the audible bandwidth it is likely to be high at audible frequencies.
Also if there are any 1 Hz to 5 Hz signals in the music signal then this will intermodulate with the wanted audible signals causing unwanted audible signals.
Also if there are any 1 Hz to 5 Hz signals in the music signal then this will intermodulate with the wanted audible signals causing unwanted audible signals.
Are you sure it's not broadband mechanical noise from "crunching" in the surround? Foam ones used to do this especially as they got a little dryed out. Also rushing air from any leakage path makes a noisy sound.
This will add modulated noise sidebands to lows. In really bad cases (I suppose) the restoring force could exhibit a noisy non-uniformity with displacement.
I am referring to the general accepted view that the eye can only resolve to an accuracy of 1 part in a 1,000, compared to the ear's ability to handle 1 part in 1,000,000. On reflection I should have used the term, "dynamic range" ...
Frank
That's encouraged me to do a little looking around, 
Some time ago I was fooling around with computer graphics, and there was plenty of material talking of such things. The video world largely tells one what is good enough, and that has relied on 8 bit encoding, per primary colour, for yonks - meaning on a grey scale where the eye is typically most sensitive there are only 256 gradations of intensity. Put grey127 next to grey128 and you have to really look to see the variation. Now up to 32 bit is talked of, but this is actually to allow free range in editing operations.
Now, the eye is capable of better, up to 90dB, but a very significant time has to be allowed for the visual system to adjust -- think of being in a room full of powerful spotlights, then immediately walking outside and looking at night sky and trying to register faint stars. What they call the instantaneous dynamic range of the eye is rated in f-stops, I see a mention of 10-14, where 10 corresponds to 1 in 1000; interestingly, very similar to digital cameras, 8-11 ...
Frank
Some time ago I was fooling around with computer graphics, and there was plenty of material talking of such things. The video world largely tells one what is good enough, and that has relied on 8 bit encoding, per primary colour, for yonks - meaning on a grey scale where the eye is typically most sensitive there are only 256 gradations of intensity. Put grey127 next to grey128 and you have to really look to see the variation. Now up to 32 bit is talked of, but this is actually to allow free range in editing operations.
Now, the eye is capable of better, up to 90dB, but a very significant time has to be allowed for the visual system to adjust -- think of being in a room full of powerful spotlights, then immediately walking outside and looking at night sky and trying to register faint stars. What they call the instantaneous dynamic range of the eye is rated in f-stops, I see a mention of 10-14, where 10 corresponds to 1 in 1000; interestingly, very similar to digital cameras, 8-11 ...
Frank
Again, the key thing is how the human physiology reacts to real situations. Music has been written for hundreds of years based on the "instinctive" knowledge that the hearing system can handle dramatic variations in intensity in a short time frame. Yet no visual, "entertaining" experiences are created which deliberately push the boundaries of what the eye can do -- we humans just don't like that type of thing ...
Frank
Frank
This has become so speculative that it is meaningless, reel it it in to some real reasearch or maybe we should just move on.
Sure it has. A number of us lighting designers were doing that back in the 1980s. Pushing the limits of visual perception. I was quite entertaining - to us, at least.
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