DiyMobileAudio.com Car Stereo Forum banner

1 - 12 of 12 Posts

·
Registered
Joined
·
393 Posts
Discussion Starter #1 (Edited)
The best Volume to test

I plan on tuning a system With a db meter and test tones from 5hz to 20khz,

Should I

A: Test at Three different volumes and adjust as necessary.

B: Test at High and low volumes.

C: Test at a normal listing level.

I know at increased volume that the sound will of course be louder But it should not matter and tone to tone from high to low level should be equal right ? Unless the amp/speaker is clipping

Right correct me if I’m wrong
 

·
Registered
Joined
·
115 Posts
This cannot be done using sinusoidal tones. This thread, http://www.diymobileaudio.com/forum/diy-mobile-audio/47742-eqing-pink-noise.html has some info on doing this. You even posted in it I believe. They only way this could conceivably work is if you used bandpass filtered pink noise in 1/3 octave bands, as that would create a scenario where a flat response across the frequency spectrum would read the same level on a SPL meter. I don' t really suggest doing this as more than an exercise because its pretty inefficient and has a lot of room for error, but its a neat idea. Just be sure you filter the pink noise correctly into 1/3 octave bands, use C or no weighting and a slow response on your meter.

As for what level, that depends. The human ear does not hear frequencies on a linear basis with respect to volume. See the Fletcher-Munson curve for more info on this. I would tune it at what you think your normal listening level will be.
 

·
Registered
Joined
·
393 Posts
Discussion Starter #7 (Edited)
This cannot be done using sinusoidal tones. This thread, http://www.diymobileaudio.com/forum/diy-mobile-audio/47742-eqing-pink-noise.html has some info on doing this. You even posted in it I believe. They only way this could conceivably work is if you used bandpass filtered pink noise in 1/3 octave bands, as that would create a scenario where a flat response across the frequency spectrum would read the same level on a SPL meter. I don' t really suggest doing this as more than an exercise because its pretty inefficient and has a lot of room for error, but its a neat idea. Just be sure you filter the pink noise correctly into 1/3 octave bands, use C or no weighting and a slow response on your meter.

As for what level, that depends. The human ear does not hear frequencies on a linear basis with respect to volume. See the Fletcher-Munson curve for more info on this. I would tune it at what you think your normal listening level will be.
Thank you for a real answer !

it just sounds like it should work, I mean theoreticaly anyway If you play 80hz, and 5khz it should play at the same volume right ? That's what eq'ing is to make all bands equall or so i thought.

I can't tone by ear beacuse I'm slighty death in my right ear, Lets just say it invloved a Q-tip and leave it at that.

It would be better to use an rta, But i don't have a laptop, I have allways been desktop person, and laptops in battery mode run to damn slow/or burn your leg so......
 

·
Registered
Joined
·
115 Posts
Please Please Please don't buy that for this purpose!!! It is only A weighted and you will get horrible results. Do you really understand what I mean by filtered 1/3 octave band pink noise? Do you have a program that will allow you to generate this? Be sure to get an SPL meter that allows you to measure a C weighted or flat response.
 

·
Registered
Joined
·
393 Posts
Discussion Starter #10 (Edited)
Please Please Please don't buy that for this purpose!!! It is only A weighted and you will get horrible results. Do you really understand what I mean by filtered 1/3 octave band pink noise? Do you have a program that will allow you to generate this? Be sure to get an SPL meter that allows you to measure a C weighted or flat response.
I got Pink in 1/3 octave from relam of excursion

LOL I know I just happen to recieve an e-mail from P.E. when I read your first comment.

Still a litlle confused How does pink noise help you level Of your EQ ? Pink noise Is just a constant steady sound. I want back an read the first thread and I think smelly meant the you want the tones in 1/3 octave (smooth and balanced response at 1/3 octave resolution)

You can't compare anything with just static noise.
 

·
Registered
Joined
·
115 Posts
Yes. You are right. You can't compare anything with pink noise.:rolleyes::rolleyes::mean::mean:
Ummm...no. Broadband pink noise has equal energy per octave or any division of octave (1/3, 1/12, 1/24) over the entire audible spectrum. Therefore since it has equal energy per octave band, your goal is make the RTA (which basically measures the SPL in each octave band) appear flat by adjusting your EQ, Xover...etc. This is the method that you are simulating with the SPL meter and narrowband pink noise.

BTW: I didn't see any narrowband pink noise on that website realm of excursion, I only saw broadband. Broadband is great for RTA measurement, but you need narrowband filtered into each 1/3 octave, or even octave bands.

Good luck!
 
1 - 12 of 12 Posts
Top