Neutral electronics are a farce...

Al, my understanding is that perceived brightness has to do with the fact that our ears do not have flat frequency response and are more sensitive to some frequencies than others, and that some forms of harmonic distortion tend to attenuate those frequencies that we hear best and are more sensitive to. So the lack of "neutrality" of our ears are as much a factor as that which comes out of the transducer.

Here is a link to the chart I’ve referenced many times (and I have framed and hanging in my listening room, a nice audiophile work of art and science) that shows at what frequency music things occur and the corresponding sensitivity of the human ear:

http://www.independentrecording.net/irn/resources/freqchart/main_display.htm

So for example if the system is perfectly flat or "neutral" what we hear is not. We will hear more of the frequencies that our ears are more sensitive to than the others which might be considered a natural colorization that we all share to some extent. How each individual reacts to that in terms of musical enjoyment, fatigue, etc. may in fact vary widely, which would account for why there is little agreement on what sounds "best".

The studies Ralph cites on how humans hear may be consistent with the idea that the frequencies that our ears are most sensitive to are the most important ones in regards to listening pleasure and minimizing "fatigue" in general.  But it does not mean that what is most "neutral" or flat" coming out the speaker will necessarily sound the best to many.

The human ear is tuned to be the most sensitive at bird-song frequencies. It also uses higher ordered harmonics to calculate how loud a sound is- its not doing that from the fundamental frequencies as such are quite rare in a pure form in nature. So if the system generates these harmonics (5th and above) even in trace amounts our ears are so sensitive to them that they will be heard, even though the distortion of the amp might be 0.005% THD.

The converts distortion into tonality. So the presence of these distortions is heard as both brightness and harshness (the 7th in particular having been known since the 1930s as a source of a metallic coloration), even though on the bench or in the room the system might measure perfectly flat.

In fact the ear has tipping points wherein tonalities created by distortion can be favored over actual frequency response errors. So in some cases its better to have none of these distortions rather than perfectly flat frequency response. 

Hi Mapman,

Yes, consistent with Ralph’s response it’s certainly true that our hearing mechanisms do not respond equally to all frequencies. And as shown in the chart you referenced their deviation from flatness is different at different volume levels.

And so distortion components, noise components, and deviations from flat frequency response will be objectionable to a degree that varies widely depending on where in the spectrum they occur.

But an obvious point that nevertheless seems worth stating is that our hearing mechanisms have the same characteristics, including lack of flatness, when we listen to live music as when we listen to our audio systems, at least if volume levels are similar. So while an understanding of the hearing characteristics you (and Ralph) cited can be important in prioritizing the kinds of distortions and colorations that are most important to minimize, we also don’t want to have the system introduce colorations (i.e., deviations from neutrality) that "correct" our hearing. Assuming, of course, that our hearing is functioning normally.

As you said earlier in the thread, "if neutral = accurate then sign me up."

Best regards,
-- Al

Al I agree with all your points.

I want my recorded music to convince me it's live, warts and all.   So I want it to be neutral and accurate. 

If it sounds any way all the time, even smooth and relaxing, that is not a good thing to me.  Its not good either if the sound is continuously irritating and  chases me out of the room.  Its OK if some recordings are and come out that way.

I know all is well when I hear a lot of variety and want to just keep on listening rather than wanting to turn it off.   Only in recent years have I achieved that.

If it sounds any way all the time, even smooth and relaxing, that is not a good thing to me. Its not good either if the sound is continuously irritating and chases me out of the room. Its OK if some recordings are and come out that way.

I agree fully!