Pink Noise VS White Noise for setting playback level (not EQ)

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miroslav

miroslav

Cosmic Cowboy
I know the basic differences between the two -- PN is equal energy per octave, WN is equal energy per frequency, and that PN is more comparable to how we hear frequencies....but I was curious if either was better just for setting the dB SPL at my mix position (and not about EQing a live sound system, which PN is better for)....?

I've now used both in in system level calibration, and it seems that when I set for 80dB SPL on my trusty Radio Shack SPL meter (C-weighted)...with PN at 80dB SPL, playback of *music* sounds louder than when setting the with WN at 80 dB SPL....if that makes any sense.

Maybe it's my imagination...but I had the system set with PN awhile ago, and marked my TC Electronics Level Pilot knob where the 80 dB SPL was...then the other day I had to pull the knob off the Level Pilot to clean something out, but the pot shaft is not one with a flat spot,...so the knob relative to the pot can spin anyway you want...and before I realized, I pulled off the knob without making note of where it was, and I lost my calibrated position.
When I went to recalibrate for 80 dB SPL....I just happened to have a WN sound file in the DAW, and didn't bother looking for my test tones CD with PN....and after setting the system, I could swear that music sounded lower in volume than before when I had it set it for 80 dB SPL using PN.

So is it just some imagination weirdness....or would it make sense for PN to have the "louder" sound with music, due to the per-octave energy tailored for how our ears work....?
 
I used PN once and used a db meter to set the knob on my interface but since then I judge it by ear.
Could be a number of things. I swear my stuff sounds different if it rains. Or I am tired.
Do you have any pictures? You could turn the shaft FCCW replace the knob and return it to the position in the picture.
 
When measuring noise of any "colour" the characteristics of the meter will determine the value. It is usual to use a "true rms " meter* for noise and other non-sinusoidal waveforms but most meters are simply average reading but calibrated rms for sine. Since pink noise has a different frequency distribution from white the meter will give a differnt value so I am not suprised that your percieved levels have changed!

*N.B. Many DVMs are called "true rms" but upon investigation I have found that most have a falling frequency response, some being as much as 6dB down at just 2kHz ref 100Hz. Such meters are "rms" for distorted mains frequencies (a bit!) but cannot be relied upon to measure widband noise accurately.

Dave.
 
Use A weighting - better approximation of our perception of sound up to 90dB

Pink noise is used for audio measures.

Cheers,
John
 
I always understood that A-weighted was mainly used in industrial noise measurements, and that C-weighted takes better account of the low-end when music is involved
IOW...with A-weighted...if the music monitor system is pushing low-end, it won't register as much on the SPL meter.

With A-weighted, the monitors end up being louder at the same dB SPL setting compared to C-weighted.
 
Yeah...even the "slutz" seem to all lean toward C-weighted.

85db a or c weight - Gearslutz.com

AFA the type of "noise" to use....I use to always use Pink, but was just wondering if purely for *level* calibration, was White equally useable since it was equal energy at all frequencies.
I guess my logic AFA setting monitoring *level*...is looking not at HOW we hear frequencies...but how the SPL is actually hitting our hearing (regardless if we are hearing all the frequencies accurately).

But that's just my logic... :)
 
if you have the master handbook of acoustics, there is a good explanation of the difference between pink and white and why pink is better for music calibration. and if i wasn't so tired i'd go get the book and list the page. :)
 
Manslick said:
if you have the master handbook of acoustics, there is a good explanation of the difference between pink and white and why pink is better for music calibration. and if i wasn't so tired i'd go get the book and list the page. :)
Click to expand...

I've read quite a bit on both...and every explanation talks about Pink Noise/White Noise from a frequency response perspective...and why PN is better for setting up a sound system/room from that frequency perspective.
I was/am curious how/if WN would differ... purely for measuring loudness....and not in a frequency response scenario.
I found nothing anywhere specifically talking about loudness measurement and PN vs WN in that scenario.

I mean, it ain't no big deal...I got Pink Noise, I got White Noise, I got all kinds of sine/square test files....etc.....etc.... :D ....so I was just curious about where/if WN would be more useable....and the whole "loudness" thing got me thinking about it.

It's like the A-weighted vs. C-weighted.....lots of opposing views, depending on who you talk to, and at the end of it all, they are all "frequency filter" curves of various degrees, though C is the least, and it seems the choice is all about perspective and reference points.
Seems like the A-weighted guys go for higher dB SPL values than the C-weighted guys....which is not unusual, since A-weighted lets you "cheat" a lot more, since it removes most of the low-end from the equation.
So PN is in some ways the same, where WN is equal amplitude at every frequency...so that's why I wondered about using WN for loudness-only calibration (I'm measuring amplitude, not frequency response of the sound system).

But again....it's just my logic, and too much thought on a somewhat minor thing (PN vs WN)... :) ...though I do want to get my monitors calibrated as accurately as possible.
 
its all egghead stuff. the specs for the boilers we engineer all call for spl in Dba. 85 is the limit, which i understand to be suited for low frequency as perceived. this makes sense to me in an organic type of scenario as opposed to measuring pure sound intensity in watts which is not subjective. i hope that makes a modicum of sense.
how it's measured i do not know. if you want some fun, read the osha manual.
 
According to Ashley Shepherd's book on mixing for video, film, and multimedia, when calibrating montiors for playback level, you should use pink noise with a C-weighting. I'm not 100% sure why (it's been awhile since reading the book), but that's what it says. Not sure if that helps at all, but... xD
 
Yeah...that's what I always used in the past Pink Noise, C-weighted.
 
C-Weighted.. Sorry. You are correct.

(My head was in STL testing...) :facepalm: and it's up to about 80dB.. boy! I was having a day.. haha.
Cheers,
John
 
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