Causes of long term listening fatigue?

I like to listen to music continuously for hours mostly at low volume levels. For me therefore, it is important to have a setup that will not cause any listening fatigue (lf).

Now I am looking for a new speaker setup and I wonder whether people could comment on the following aspects:
1. is 5-ch more susceptible to lf than 2-ch?
2. are there quick tests so that one can determine whether a given speaker will tend to give lf? I ask this because in a shop it will be difficult to assess this due to lack of time and differences in acoustic environment.
3. Which speakers do you know in the price class $3k that do have lf problems and which ones can be recommended in this respect? (difficult question, I know).

Thanks for input.
The biggest cause of listener fatigue is worrying too damned much about your gear.
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IF there is the slightest degree of "brightness", I know something isn't going to work for me.
Consider Vandersteens or similarly smooth speaker if in fact your speaker is lean or bright. If any component sounds very exciting upon first listen, it might be a problem over time. I also agree about electronics and will add cable problems as well. Watch out for ultra detailed sounding might lead to fatigue over time.
I pretty much agree with Elizabeth, especially since you stated that your preferences are for listening at low volume levels.

However, I will give you my opinion on speakers for low level listening, since you appear to be shopping for them at the moment. (This advice is worth every penny you are paying for it!)

I recommend planer type speakers for listening at low sound levels. These speakers seem to work better than standard dynamic speakers at lower sound levels. They seem to image and soundstage better, IMHO.

That being said I actually listen at loud sound levels and now use dynamic speakers. I used to have planer type speakers and they did seem to work better at lower sound levels. (Consequently, dynamic speakers seem to work better at loud sound levels.)

My opinions of course. You might want to do a search here and on audio asylum for speakers that excel at low volume levels.

Good Luck!
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First off, let's assume you've narrowed down your shortlist to exclude loudspeakers that are obviously harsh or edgy, and now you're trying to choose from among a few very good-sounding speakers which is most likely to remain non-fatiguing over the long haul.

Listen to a wide variety of music, at normal volume levels, lower than normal, and higher than normal. What you're trying to do is ferret out sublte colorations that will become distracting over time, and also make sure the speaker's characteristics don't change drastically with volume level. I've made the mistake of taking on a loudspeaker line that sounded great at medium and high volume levels, but sounded dead and lifeless at low volume levels. Similarly, you want to find out if a speaker is going to get too bright or forward on loud peaks.

Here are two tests you can do that are in my experience reliable predictors of whether or not a speaker will become fatiguing long-term:

First, turn the volume down much lower than normal, down to near the threshold of audibility. The bass will pretty much disappear, which will tend to unmask midrange problems. Also, this will tell you if the speaker has good resolution of detail and nuance. Does it still sound richly detailed, lively, and tonally smooth (even though the bass will be missing)? If so, that's a very good sign.

Next, turn the volume up a bit louder than normal, and walk out of the room, leaving the door open. Listening from outside the room, all you can hear is the reverberant field. Is there a convincing illusion of live music happening back in there, or is it obvious that you're hearing a pair of speakers? Note that live instruments still sound convincing from the next room. Unfortunately relatively few loudspeakers get the reverberant field right, and in my opinion this is a critical factor when it comes to listening fatigue. Let me explain:

The ears localize sound sources in a reverberant environment by suppressing the directional cues from repetitions of the original signal (reflections) arriving after a very short time interval - .68 milliseconds, or the time it takes for a sound wave to travel the roughly 8 inch distance around your head from one ear to another. This suppression of directional cues from reflected sound is called the Haas effect or precedence effect. Now, how does your ear/brain system determine if a given sound is a reflection, or a brand new signal? It compares the sound with other recently heard sounds (dating back about 40 milliseconds) to see if it's a reflection. This is why I can speak to you from across a room and even though 90% of the sound power from my voice that reaches you ears is reflected sound, you can close your eyes and unerringly tell exactly where my mouth is.

Now when the reflections begin to sound less and less like the first-arrival sound, the ear/brain system has to work harder to properly classify them as reflections or new signals. And this situation arises when a loudspeaker's varying radiation pattern results in a significant discrepancy between the tonal balance of the first-arrival sound and that of the reverberant sound. The result is often a headache after about 20 or 30 minutes, even if the sound is initially very exciting.

Note that during the .68 to 40 millisecond interval when the precedence effect is suppressing directional cues, the timbre (tonal balance and texture) and subjective loudness of the sound is still being influenced by the reverberant energy. So assuming the first-arrival sound is tonally correct, it would be nice if the reverberant sound reinforced that correct tonality. The ideal is you want the reverberant field to sound like the direct sound with the room's acoustics superimposed on top, as this is what a live instrument would sound like in that room. Listening from outside the room lets you zero in on this reverberant field sound.

A loudspeaker that is exceptionally non-fatiguing is the Gradient Revolution. The Revolution is unusually free from distracting colorations and maintains an exceptionally uniform radiation pattern up and down the spectrum. Designer Jorma Salmi went to great lengths to get the reverberant field right. The top end can be a wee bit on the laid-back side, so a lively amplifier is often a good synergy. The Revolution retails for five grand, but used ones often go for less than three grand. Disclaimer - in case you haven't guessed, yup I'm a Gradient dealer.

Maggies tend to do a good job with the reverberant field, as do most full-range planars. You could pick up a refurbished pair of original Quad ESL's, the "57's", for well under three grand. And then there are conventional-appearing speakers that are designed to give a good power response - I surprised with how good the little Avalon Symbols sounded from outside the room. A conversation with designer Niel Patel revealed that he gives high priority to creating a tonally correct sound field, not just a certain desired on-axis response. Nope, I'm not an Avalon dealer, but may become one in the future.


If you never change speakers, how did you eliminate all speakers as a source of listening fatigue?
listener fatigue is a function of the money you've spent on your the monetary investment increases, the anxiety and worry we experience over neutrality, detail, bass slam, etc, etc increases (at least exponentially)
relax and don't buy into the idea that throwing silly amounts of money at your hifi is going to solve fatigue problems. if your financial stake in your hi-fi isn;t the cause of listener fatigue the you either need to admit da Nile isn't just a river in Egypt, take this hobby less seriously, scrap your system and start over again or sell your gear and buy a Tivoli radio.
. it really sucks to suspect the $$$ (read "most or all of your discretionary cash) you just spent on an amp, pre, cdp, etc has not just failed to improve the listening experience but has actually wrecked a system we were able to live with and listen to without "serious" complaint.
i'm not saying we should abandon our quest for the grail as audiophiles, nor am i saying that there is no relationship between gear and unpleasant ear/headaches some of us suffer as time passes during a listening session.
we should all laugh at ourselves once in a while, we are nuts right?
i'm not trying to fan flames here, but if listener fatigue is your biggest problem in life you've got a sweet thing going.
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I'm a bit more simple minded than the other respondants.

The only way I ever know if I'll have listening fatigue with a pair of speakers is to buy them and live with them in my system.

If I can read a good book for hours while sitting in front of them, they're keepers!
I had a very mellow sounding system (read uninvolving) and finally decided to upgrade the speakers. I have tried to tame the highs for the past 2 years because these speakers brought a lot of new things to the listening experience. One of these new things turned out to be listener fatigue. Not to question a POPE or anybody of that level, but a speaker can definitely cause fatigue when hitched up to a less than synergistic setup. This hobby is all about synergy and as a DIY'er, I can tell you that changing a tweeter resistor value by as little as 1 ohm can make a system go from just right to bright. Just my 2 cents
I'm with Gunbei. If I feel compelled to sit in front of the stereo and read then all is right in my little world. However, if I've changed something and thrown the system out of wack, then the only time I feel compelled to go into the listening room is to vacuum and dust.

Elizabeth, excercising the sarcasm muscles again? LOL

Wouldn't it be nice if we had some idea what Karman's electronics, including sources, were? Might also be nice to know what, if anything he has done about set up and taming reflections. Ditto room size. With that info we might be able to give his some useful advise. At this juncture his listening fatigue could be caused by anything in the chain.

Karman, care to enlighten us?
What kind(s) of music are you listening to? If you are listening to music for hours on end at low volumes I suggest that you will not make great gains in overcoming your fatigue by simply making changes to your system, however great or small. I listen to various genres of music; rock, jazz, and classical to name the basics. And yet there are various subgroups in each genre, some quite busy and forward, others simple and laid back. Mix it up. Sometimes you need a little decaf in the midst of the double shot expressos.
When you use wall treatments that suck info away from the original signal....or if your room has only echo....your info is now bounced around....Ever read a page in a book and gone to the bottom and then realized you don't remember what you read...You went through a misunderstood word and you failed to clarify it...keep reading and you will give up on the subject....well suck lots of the info out of your music and give up....Life is an applicable philosophy,HI-FI is part of life..Not the center of the universe. So enough with 2d answers to a 3d world
Quad Electrostatics have low listener fatigue and excel at giving lots of details at low levels. The 988 is out of your price range and the 57 may be too difficult to accomodate.

But there seems to be a decent selection of 63s in the 1500-2000 range and that should be an ideal speaker for you. A decent tube amp or something like a Pass Aleph should get you what you want.
wall treatments do not suck info away as has been stated above. They make imaging and soundstage sharper and less distorted. the speakers will sound more accurate. Reflections that come straight off the wall, ceiling or floor and collide with the frequnecy radiating directly from the speakers at the listening position can cancel or exaggerate frequencies along the whole tonal spectrum. Proper room treament will help realize your sytems potential!your room is a 'component'.

keep it fun!
I suppose most Audiogoner's listen to music more than most others. That might just be the problem. I sometimes wonder if I'm the only one here that gets listener fatigue listening to live unamplified music. Sure I can listen for hours and hours, but, there comes a point when enough is enough. My simple little brain needs a rest. On to something else, or nothing else for that matter. I sometimes wonder if some people sacrafice fidelity for longevity. FWIW, if you have the room, I too would endorse used Quad '63's "in that respect".
LF is caused by odd-ordered harmonic content in the signal, usually harmonics of the 9th order and beyond. These harmonics are emphasized by the use of negative feedback in amplifiers and by non-linearities in transistors (and to a lesser degree by non-linearities in pentodes).

IOW, LF is usually not caused by speakers alone. To reduce odd-ordered harmonics, one will have to use a tube amplifier with little or no feedback. Such an amplifier will need a linear impedance curve from the speaker, so if low LF is your main priority, then you now know what you have to look for!
Brightness caused by speaker and/or room is numero uno. Also hardness and grain I cannot deal with anymore. So I feel any component or possibly a combination of components can cause LF.
You are correct- the reason is that our ear/brain systems are tuned to accept odd-ordered harmonic content as *the* loudness cue (read: Listener fatigue) in anything we hear. Anything that causes an emphasis to those harmonics results in listener fatigue.

Bright sounding electronics get that reputation through the negative feedback they use. Speakers may get that reputation for a variety of reasons, not the least of which is that improper relationships between the amp and speaker (transistor amp on a high efficiency speaker, for example) can cuase the speaker to become shrill when it is not normally.
I agree with the electronics as the starting point to address LF. Two months ago, I replaced my modified Music Hall CD25 cdp with an EAD CD1000 series III cdp. I changed nothing else to include my listening environment. The sound was much easier on the ears. In my system, the CD25 sounded very detailed, almost too detailed. The CD1000 is much, much smoother sounding, with a warmer feel.

Just my opinion from a very recent experience.