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Rethinking Listening Fatigue

Listening fatigue to me has always been a sure sign that something was wrong with an audio system.

It is a useful test of a system, because it is not always immediately apparent - a fact which has undoubtedly helped Dr Bose get rich.

I have always thought fatigue was mainly a product of digital, overly bright tweeters, and/or a sonic signature that puts too much emphasis on "resolution" and not enough emphasis on high quality midrange.

But lately I am wondering if I have been oversimplifying things.

As you can see in my system link, I am using a pair of ATC SCM 7's with a pair of Behringer amps used as monoblocks for my desktop and PC audio.

Recently, I have added a Hagerman Technology USB interface box, which goes into an Audio Research DAC 5.

To my ears, the ATCs have a slightly laid back, non fatiguing sound typical of many English products which suits my tastes just fine, particularly for very nearfield listening.

What is curious, however, is that I am starting to realize that this system sounds really different depending on the volume and/or the time of day.

At times, this little system sounds wonderful. I feel I can listen to it for hours, with the speakers < 3 feet away from my ears and in many ways, I enjoy it more than the big system.

Detail for both music and movies is very clear and I have especially noted that I am better able to discern dialogue with these speakers, without ever feeling like the sound is too "etched' or embossed.

At other times, however, I feel quickly fatigued and suddently overwhelmed with an unpleasant this is way too loud, the music is congested and I must be bothering my wife sensation.

No one I know has ever described ATC monitors as fatiguing, so I am starting to wonder:

1) Despite relatively high power of the Behringer amps in a monoblock configuration, is it possible that they are overdriven and distorting at not terribly loud levels?If so, would this type of distortion, rather than overly hot tweeters, be a more obvious culprit for fatigue?

2) Or could grunge in my AC also contribute to listeners fatigue? Would some of you recommend a line conditioner rather than an upgrade to the amps for this desktop system?

The fatigue I am trying to describe always manifests itself as 'this is uncomfortably loud' sensation.

Thank you for your thoughts and comments on this and the topic of listeners' fatigue.

cwlondon
cwlondon
sns
653 posts
 
Beyond recording quality variability, which should be quite obvious in a high resolution system, I've found a strong correlation between quality of AC and good digital sound. I suffered from listener fatigue from time to time until I resolved all AC issues within my system. I've tried dozens of power conditioners, power cables, even AC receptacles, all make a difference within a high resolution system.

The uncomfortably loud sensation you speak of sounds like it may be an overly forward presentation, this can make things sound louder as the sound is more greatly projected into room and listening position. I've been able to resolve this purely with power devices.

The randomness of the problem also speaks to AC issues, power quality fluctuates quite a bit in many areas.
kijanki's avatar
kijanki
3,575 posts
 
It probably doesn't apply to your case but often amplifiers with very deep negative feedback sound fatiquing even if sound is not overly bright. After each impulse feedback is a little late and output transistors go to saturation and need a moment to return from it(charge trapped at the semiconductor junction). We don't hear it because our brain fills-in short gaps in the sound but it makes us feel fatiqued after a while. It is called TIM (transient intermodulation) and it was very common in early transistor amps since designers used negative feedback to lower harmonic distortions to absurd levels.
cwlondon OP
1,198 posts
 
This is great - thanks for answers so far!

Re recording quality, yes I would agree nothing is more fatiguing than a bad, overly compressed recording.

But no, I would say these observations apply even while listening to old audiophile favorites, albeit after ripping in EAC to the hard drive.

iTunes may be a culprit here, as I have been (I confess!) downloading various .99 old favorites. But pretty sure I have been doing this in "lossless".

Interesting that no one is pointing fingers at the amps yet, as I thought this might provoke another round of Behringer bashing.
cwlondon OP
1,198 posts
 
Kijanki

Rather, not pointing fingers at Behringer...

Thank you for your interesting point on negative feedback.

cwlondon
blindjim
2,837 posts
 
to point the finger at one aspect of your system now probably isn't the most appropriate way, though for now, I'll go along with SMS' note. A decent passive filter shouldn't run much and it can translate into another rig or be sold again if it's not the solution. Even a simple system has several parts to it. Anyone of which can induce a problem.

iTuens too might be a part of the issue. Though I'd not put much money on it. I did notice a bit of a difference after installing an ASIO driver I bought online... and a far greater (mo better) difference when I switched to J River's player. Way better!

My take is from what you said initially... certain hours of the day things get wanky... regardless the music being played. Well that sounds like power gremlins are kicking up their heels now and then.

At the offidce all sorts of things can be routinely energized for a time and induce junk onto the grid. PC back up power supplies are known to be really bad for this Cell phone chargers, fax machines, etc. especially if close by aren't audio friendly items.

Some sort of good filter ought to do it for you. Like a PSA Duet or even a PSA UPC 200 should do the trick, given a decent power cord is used as the supply. you might even get away without having to buy a better one than they come with too.
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