Sine Wave level check for hearing test

[JoachimStrobel]

I like to check the lowest level where I hear a certain frequency to check my hearing versus ISO226 or similar curves. And I want to do that with my speakers, and the Umik hanging above my head.
My room’s background noise is around 45-50 dB from some low frequency rumble. If I want to measure the lowest level of a 1 khz sine wave that I just can hear, then I do not know how to do that in REW. If I bring up the RTA it will report the overall level from 20-20khz. I can see the 1khz peak and read this level off the chart, but this is rather crude - is there not a more elegant way doing that? Or am I missing something?

 

[John Mulcahy]

Not really. You could use the SPL meter on A weighting to reduce or remove the low frequency contribution. I suspect that isn't a reliable way to test your hearing, however. The level of the signal the UMIK picks up will be affected significantly by very small movements in the position of the mic or your head.

 

[AudiocRaver]

Agreeing with John, we normally look at frequency response curves with some amount of smoothing applied, If you look at an "unsmoothed" curve, you will see a huge amount of variation, especially with deep, narrow dips in the response, which are less noticeable to us than peaks in the response, and are generally ignored. So you might be picking a frequency that lines up with one of those dips and get a low output at that frequency. Plus, as John indicated, the response for a sine wave can change drastically with a small change in ear position. An unreliable measurement is pretty much guaranteed.

The headphones used by an audiologist are calibrated for that purpose. If you are going to use a speaker for such a test, you might try to use 1/3 octave bands of pink noise. Most of the above problems would be avoided. REW can not generate bands that narrow, though, so you would have to find a source for such noise files that you could then play through your system and do your "hearing test" that way.

 

[JoachimStrobel]

Thanks for the advice. I did first measurements. And true, above 7khz my perception depends a lot how I turn my head. I am using two front speakers. Headphones omit that problem as they hit my eardrums directly. The Umik seems fine (down 90 deg), it sees a constant response with little changes away from linear ( I Eqed the system before with Dirac and a flat target curve)

 

[JoachimStrobel]

I did complete some measurements that I posted here:

Hearing EQ

(This Post was inspired by https://www.audiosciencereview.com/forum/index.php?threads/hearing-loss-a-hobby-fades-away.7316/) A couple of weeks ago I embarked on a project that I like to share and ask for comments: Ear or Hearing EQ. After having toyed with Room EQ, I thought it would be cool to...

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