So, You Can't Hear...

[ermghoti]

Just took one of those online tone-generator tests on the lappy through my Senn HD280's. About what I'd feared, things start getting quieter at 13k, I have total silence (other than the constant peel of tinnitus) from 17k up.

I guess since, if what I've read is accurate, the great old tape formats couldn't catch anything higher than 16k or so, I can still hear enough to record and mix.

My question: if I can't hear a frequency, should I leave it flat, or should I low-pass, to eliminate any nastiness, which I would be totally helpless to address? Does a recording ever really need adjustment above 16k?

 

[miroslav]

Does a recording ever really need adjustment above 16k?

Rather than doing hearing tests with single tones....play some nice broadband music through a decent stereo EQ. Play something with plenty of HF content...
...then cut the HF hard...
...does the music sound different or the same to you?

I have an EQ that has an "air band" that goes out to 40kHz.
I sure can't hear even at 20kHz...but I can hear the effect of that "air" band when it's cut in/out.

 

[mattr]

I sure can't hear even at 20kHz...but I can hear the effect of that "air" band when it's cut in/out.

What kind of slope does that filter have on it? It could be affecting frequencies right down into your audible range, which would explain why you can perceive its effect.

Just a thought

 

[miroslav]

I would have to look at the specs....though I don't thnk it dips down too far when it's set to 40kHz. If I set it to 20kHz for the air band...then yeah...

But my point was that even though you might not hear a single 16k test tone...removing all the HF content from a full mix will be noticable.

 

[Lt. Bob]

What kind of slope does that filter have on it? It could be affecting frequencies right down into your audible range, which would explain why you can perceive its effect.

Just a thought

there's been quite a bit of research that seems to indicate that the presence of energy above the audible range seems to have an effect on how we hear things that are in the audible range for some reason. Many high end speakers will have super tweeters that are just for covering the range above 20k on up to 40k or so. And that wouldn't really have any effect on lower freq's. But turn the things off and there's a difference in how they sound.

 

[Bristol Posse]

Just took one of those online tone-generator tests on the lappy through my Senn HD280's. About what I'd feared, things start getting quieter at 13k, I have total silence (other than the constant peel of tinnitus) from 17k up.

I guess since, if what I've read is accurate, the great old tape formats couldn't catch anything higher than 16k or so, I can still hear enough to record and mix.

My question: if I can't hear a frequency, should I leave it flat, or should I low-pass, to eliminate any nastiness, which I would be totally helpless to address? Does a recording ever really need adjustment above 16k?

I'd be surplrised if the speakers on your laptop went much above 16k anyway which could explain why there is nothing there , typlically a laptop built in speakers response curve runs from about 80hz to maybe 16-17k but most of the action they will even begin to represent is much narrower maybe 180hz to 10-12khz. Even plugging in decent speakers that can fo 20hz-20khz may be no good, a lot of built in sound cards do not have a flat frequency response but drop off in the high and low ranges with all kinds of crazy peaks and troughs before you get to the drop off
Definitely not a good option to test the upper limits of your hearing range on

 

[SouthSIDE Glen]

My question: if I can't hear a frequency, should I leave it flat, or should I low-pass, to eliminate any nastiness, which I would be totally helpless to address? Does a recording ever really need adjustment above 16k?

While it's rare that anything above 16k needs adjustment, there are some specific real world cases (all that mumbo jumbo about 20k+ stuff aside) where there may be some problems up there - examples would include converter aliasing, second-order sibilants, poor quality MP3 conversion, etc. Note that these are almost always in the form of too much HF, not of not enough.

That said, I'd say, if you can't hear it, don't mess with it.

EXCEPT....

Many/most of the kinds of problems mentioned above are fairly readily identifiable through a frequency analysis of some type. Certainly all three I mentioned do leave identifiable fingerprints in either an FFT or waterfall-style spectral analysis. If you learn to read those visual fingerprints pretty well, you can sometimes ID and correct HF issues that you might have trouble otherwise hearing.

G.

 

[miroslav]

there's been quite a bit of research that seems to indicate that the presence of energy above the audible range ….

Though even if we stay within the human hearing range...stuff between 16k and 22k would fall in that *official* audible range...

I just couldn't see cutting everything above 16k just because I wasn't able to hear test tones at or above 16k. I still say there will be an effect on the stuff you do hear below 16k...at least I know that notice it.
My hearing drops off sharply too up in that range when I'm running test tones, but if I just cut things hard above that point when listening to broadband music tracks...the music all of a sudden goes dead/flat sounding.

I just don't know at what increments you would need to test to have a very accurate hearing test.
Like....if you can't hear a pure 16k tone and a pure 18k tone...does that mean 100% that you will not hear anything in-between them…at any level?
I don't think our ears only focus on the typical test tones we often use....and without getting into another drawn out debate on psychoacoustics…IMO…our ears are always picking up all those sound waves and processing them...maybe not so we perceive them as *heard* tones...but they do get in there.

 

[Lt. Bob]

I'd be surplrised if the speakers on your laptop went much above 16k anyway which could explain why there is nothing there

he said he was using Sennheiser HD280 headphones. Those definitely go to 20k but your point about the soundcard seems plausible.

 

[ermghoti]

I do consider my soundcard suspect, but I don't doubt I have hearing loss.

Thanks for the other responses. I considered using a SA, and treating anything that looked horrific. I don't mix with my eyes, but how much trouble could I really cause my self at 18750Hz?