Hearing and Aging

[ChopsMX5]

Here's mine, just for poohs and giggles.

• No ambient noise in the room/house
• Two 120mm fans slowly runnig in my PC, making virtually no noise
• AMD Athlon 3400+ 64 bit processor
• Microsoft XP Pro x64 Ed
• SoundBlaster Audigy2 Platinum
• Little Dot Micro+ Headphone Amp
• Grado SR-325 Headphones

I'm a 32 year old male and have been a little harder on my ears thant I probably should have over the years, constantly going to concerts, night clubs, having loud car stereos and home systems for the past 14 years.

As a side note, I ran the test with and without the Little Dot head-amp and the results were the same. I also ran the test through a pair of Sony MDR-7506 headphones (with/without amp) and through my bedroom stereo with DIY 3-way tower speakers I built 11 years ago, and all gave similar results. I also tested each ear separately with both headphones, with matching results.

[Fred Sanford]

Fred

Run the test in the night time when all the ambient background noise levels drop down. And with the washing machine off! By the way do you hear any computer noise on the headphones before playing any sound program material?

Not sure what you mean by computer noise. I wouldn't hear the fan or the drive spinning, and didn't hear any data chatter.

Ambient noise levels? I've currently got about 4 bozos firing off shotguns in the field in front of my house. Don't think that calms down after dark, either. Who'd have thought I'd hear more gunshots here than in NYC...

I could hook the laptop up to the 4333As tomorrow...

je

[JSF13]

Ran a graph for myself. Don't know how to copy it here but I could sure see why I have to crank my mids down.

[JBL 4645]

Ran a graph for myself. Don't know how to copy it here but I could sure see why I have to crank my mids down.

JSF13

Look at the keyboard and look for (Print Screen) its above delete Insert buttons.

Press it and then look for (Paint) in the start button section once you’ve found it right hand click and paste.

[JBL 4645]

You’ll see Image select decrease the size by inputting even numbers in the horizontal and vertical save the image under Jpeg, then look though you’re pictures folder select the picture by using the Lansing heritage sites own picture upload. Press open it should take a few seconds upload.

[JSF13]

Must be doing something wrong because I get an error message that "paint can't read this file"

Anyway here are the numbers,low to high.No numbers for 12 or 16 as I can't hear them.

-12,-21,-24,-27,-30,-36,-39,-42,-42,-42,-36,-33,-24,-24,-21,-3,-6 -,-.

[cvengr]

This topic has caught my attention recently for a number of reasons.

Firstly, there are a number of manufacturers of speaker/transducer systems which now use ultrasonic systems to project sound over large distances, then the air or medium transmitting the sound attenuates and produces apparently three subharmonics, of which at least one is in the audible range at further distances.

This was recently used in a commercial billboard advertisement in or near SOHO with an advertisement for Paranormal State, and A&E series on the paranormal. http://www.holosonics.com/PR_AE.htm

I also understand that many recent developments in hearing aids don't so much amplify the sound patterns entering the ear, as much as redirect the sound with ultrasonics so that audible frequencies are heard further down the ear canal. In effect, much of the attenuation of the sound is due to hair growth within the ear which filters out audible frequencies, so the solution has been to refocus the sound waves to constructively interfere and become audible simply further down the ear canal past internal blockages.

I've noticed something similarly with recent specifications on transducers. Many tweeters today are being produced which range in output far beyond 20,000 Hz (generally regarded as the upper limit of audible sound).

I was wondering if anybody in this forum had been involved in the design and production of these higher ranging devices. Were they designed to operate at the higher frequencies or was that simply a collateral benefit in deigning the devices to meet lower frequency parameters?

I must say, I was stunned when I read your post. I think you're right in everything you've posted. Hard to believe, but I do believe we can hear much higher than 20KHz. The brain and sensory organs (still the most powerful "computer" in existence IMHO) can certainly compensate for frequency response abberations from hearing loss/damage over time, with the inherent limitations of "hearing sytem self-noise" as you put it.