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Discussion Starter · #1 ·
This may be the wrong forum as I haven't even run REW yet having only just discovered it. However:

I only run a two channel stereo setup but have struggled for some time with a harshness in what I think are upper mids that gets worse with volume increases. This problem has continued through amp & speaker changes so today I played around with some fixed frequency test tone WAV files. This has shown that at 2KHz something odd is going on as 2KHz sounds much louder than 1KHz or 4KHz & I'm guessing this is my problem. I will start to gather the hardware required to run REW to get some proper measurements but wondered if I could get some pointers as to possible causes & solutions in the mean time?

The room is 18' x 12' with carpet over a concrete floor.
Walls are bare painted but the problem also existed when they were papered.
The problem also exists regardless of speaker position.
The only glass is a double width sliding patio door with small windows either side. This occupies some 12' of one of the 18' walls. There are fairly thin curtains that run the full width & it doesn't seem to make any difference whether they're open or closed.

I'd be extremely grateful for any pointers even if it's just other threads/sites to read up on.
 

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Discussion Starter · #3 · (Edited)
Thanks but as I said, speakers (& amp) have been changed several times because I too thought that was the cause. Mission M34i > Acoustic Energy Neo 3 > Monitor Audio RS6 > Spendor A6. All have displayed this tendency to a greater or lesser effect with the Missions being the worst & the Spendors being the best.

Amp is currently a Leema Pulse III & I've previously had Arcam A85 & Rotel RA-1062.

Edit
I played with a signal generator app this morning. Manually sweeping between 1KHz & 5KHz, there seems to be audible ringing (for want of a better description) between 2.5KHz & 3KHz that peaks/intensifies at 2.7KHz. This is just by ear & very small movements of my head increased/decreased the effect significantly.

On with the search for a decent mic as there doesn't seem to be much available for a reasonable price in the UK, other than the real cheapo Radio Shack.
 

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Thanks but as I said, speakers (& amp) have been changed several times because I too thought that was the cause.
Then it could likely be an acoustics issue (although I can’t rightly say I’ve heard of one of this nature). REW can help you trace that down, with help from some of the folks here who are well-versed in that area.

Alternately, it could simply be that your ears are particularly sensitive to that frequency range. Again, a frequency response measurement with REW could tell us if there is actually a measurable spike in the 2 kHz range or not.

An easy fix would be outboard parametric equalization, but that would require you moving up to full separates.

Edit
I played with a signal generator app this morning. Manually sweeping between 1KHz & 5KHz, there seems to be audible ringing (for want of a better description) between 2.5KHz & 3KHz that peaks/intensifies at 2.7KHz. This is just by ear & very small movements of my head increased/decreased the effect significantly.
Yeah, such is the nature of sine waves in that frequency range. They really aren’t the best test signal for determining a problem like this – at least, not by ear.


On with the search for a decent mic as there doesn't seem to be much available for a reasonable price in the UK, other than the real cheapo Radio Shack.
You might check with Cross Spectrum (see the sticky thread in Mics/Meters Forum) - I think they’ll ship internationally.

Regards,
Wayne
 

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Discussion Starter · #5 ·
Thanks Wayne.

The ringing doesn't occur on headphones or if I move very close to the speakers so it does seem like a room issue rather than my ears. Can you give an example of what you mean by external equalization? I'm guessing a DSP based equivalent of ye olde graphic equalizer sitting between a pre-amp & power?
 

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I just finished the Get Better Sound book and video by Jim Smith and he discussed rooms with carpet over concrete. He says that concrete sub-flooring it is generally a bad idea acoustically but he gives treatment options. I don't know if this will help your specific problem but having just finished the book and DVD I consider it a essential resource regardless. Hope this helps.
 
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