Metering - Sine wave vs. square wave

Waltz Mastering

Waltz Mastering

New member
I've never been a big metering kind of guy, but I am trying to get a understanding of the popularity of two specific kinds of meters used to measure rms as an idea of who uses which and on what daw or platform.

Some meters use the AES17-1998 standard - where a sine wave is used for calibration.

Some daws incorporate standard meters that use a square wave used for the calibration instead, where the the reading will be 3dB lower than the AES 17 calibrated counterpart.

Do you know which one you use when reading rms levels? Which one is it?
Name of meter and daw?
 
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I had gleaned it was the other way around, that a 0dBFS peak sine wave would read 0dBFS RMS under AES-17.

Bob Katz talks about it here:

http://www.gearslutz.com/board/mastering-forum/358907-s-aes17-not.html

I don't like it though, because a square wave DOES have a higher RMS than a sine wave, no point pretending otherwise. I mean a 0dBFS peak square wave will read +3dBFS RMS under AES-17. How is that supposed to make sense :confused:

Simple math, square all samples, average them, take the square root. Anything else is engineers trying to fool themselves . . .
 
You could be right. I was told that the TT Dynamic Range Meter uses the AES Standard AES17-1998 - where a 0dBFS sine wave is calibrated to read -3dBFS

I could have received bad intel. Hopefully someone can clear this up.
 
Waltz Mastering said:
I never been a big metering kind of guy, but I am trying to get a understanding of the popularity of two specific kinds of meters used to measure rms as an idea of who uses which and on what daw or platform.

Some meters use the AES17-1998 standard - where a sine wave is used for calibration.

Some daws incorporate standard meters that use a square wave used for the calibration instead, where the the reading will be 3dB lower than the AES 17 calibrated counterpart.

Do you know which one you use when reading rms levels? Which one is it?
Name of meter and daw?
Click to expand...

Good Question. Which Type of DAW are You using?
 
Waltz Mastering said:
You could be right. I was told that the TT Dynamic Range Meter uses the AES Standard AES17-1998 - where a 0dBFS sine wave is calibrated to read -3dBFS

I could have received bad intel. Hopefully someone can clear this up.
Click to expand...

AES Standard AES17-1998 - where a 0dBFS sine wave is calibrated to read -3dBFS
Sounds Like a more feasible measuring point. I would not want to calibrate my levels to 0 dBFs and get a false indication that I am really using +3dBFs. Although the squarewave itself sounds promising in the way of collecting an average of samples to coincide with the levels. I do not see why there cannot be a squarewave utilization within the AES Standard AES17 spec at -3dBFS.

I thing the Squarewave spec at +3 came from the fact that back in the early 90's every how to digital recording book said to set recording levels at -6dB.
that would mean if you set to -6dBFs you would be close to -3dBFs without the thought of potential clipping at 0DBFS and above(going in the red). Thats were I have found the most clicks, and pops to occur on analyzed recordings.
 
Waltz Mastering said:
You could be right. I was told that the TT Dynamic Range Meter uses the AES Standard AES17-1998 - where a 0dBFS sine wave is calibrated to read -3dBFS

I could have received bad intel. Hopefully someone can clear this up.
Click to expand...

Hey Tom,

I tried that plug in SoundBlade. Looks cool, but who trusts meters ...

I thought that it was AU only (apparently not), which DAW are you using?

If Mac you may want to check out:

http://www.channld.com/dwnldpgap22.html

If PC:
http://www.orban.com/meter/

Both support ITU BS.1770
 
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Thanks.

I wasn't looking for a meter per say, but just trying to understand the difference between the aes -17 and standard digital meter and trying to get an idea what most people are using.

The main reason I ask is, There was a thread concerning the "Dynamic Range Day" thing where the op said conservative masters should have an rms at -10 dBFS...and I new that that was just wrong, so I asked what kind of meter he was using. He said the TT, and that was aes-17 which corresponds differently to conventional daw meters (difference of 3 dB).

This lead me to think that not that many people at all use the aes -17 measurement and was a bit confusing.

The programs that I primarily use are PreMaster cd, Pro Tools HD 3 and Wave Editor.
 
; )

I use set of Dorrough meters and also have a set of VU's in storage...

My thought was.. these guys that are promoting dynamic range are sort of doing a dis-service to themselves by also promoting the use of a meter and scale that confuses people who are familiar with another scale that reads differently..so when they are saying -8 dB, to a majority of other people, it's really -11 dB, but they don't know that.
 
Yes, for several years this has been un-intentionally the most funny thing with all those threads about level and the loudness wars and such...

'Ohh, it's -9dB RMS' :eek::eek::eek:

Depending on how this was measured, it could be one's own software could interpret this as either -12 dB RMS, -9 dB RMS, or -6dB RMS.
That's alot of difference...

Still, it looks like most people use the square-wave measured method, and those who aim for being 'political correct' use the AES-17.
:D


There is one easy way to find out, though, what your own software is using, and that is to use a wave-generator and see for yourself.
 
Njal Frode Lie said:
Depending on how this was measured, it could be one's own software could interpret this as either -12 dB RMS, -9 dB RMS, or -6dB RMS.
That's alot of difference...
Click to expand...

AES should have proposed a different label, so instead of "dBFS RMS AES-17", it could simply have been "dBAES". Then there would be no confusion, because dBFS has a specific meaning, and RMS is a specific mathematical calculation.
 
Njal Frode Lie said:
Yes, for several years this has been un-intentionally the most funny thing with all those threads about level and the loudness wars and such...

'Ohh, it's -9dB RMS' :eek::eek::eek:

Depending on how this was measured, it could be one's own software could interpret this as either -12 dB RMS, -9 dB RMS, or -6dB RMS.
That's alot of difference...

Still, it looks like most people use the square-wave measured method, and those who aim for being 'political correct' use the AES-17.
:D


There is one easy way to find out, though, what your own software is using, and that is to use a wave-generator and see for yourself.
Click to expand...

mshilarious said:
AES should have proposed a different label, so instead of "dBFS RMS AES-17", it could simply have been "dBAES". Then there would be no confusion, because dBFS has a specific meaning, and RMS is a specific mathematical calculation.
Click to expand...

This is what I was thinking. It seems they are trying to hold on to a measurement standard that came about before digital audio was commonplace and are shooting them selves in the foot and creating more confusion in the meantime.
 
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Waltz Mastering said:
This what I was thinking. It seems they are trying to hold on to a measurement standard that came about before digital audio was commonplace and are shooting them selves in the foot and creating more confusion in the meantime.
Click to expand...

AES seems to be a giant foot-shooting organization to me :D

I think they were trying to create a VU meter calibration for dBFS, but they missed. If 0VU = -3dBFS RMS, then a 'good' mix would be around -10VU. That's too low to be useful on a VU meter.
 
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