Understanding RMS Calibration?

[PT user]

Im trying to calibrate my Avid Omni for 5.1.
Most things Im reading say start with pink noise RMS. Using Signal Generator and selecting a 1khz tone or Pink Noise comes up at -20dbfs on the meters as well as the plug in when SG is set to peak (default) . If I select RMS it obviously no longer correlates to - 20 on the meters within PT.

Should i be adjusting the plug in so it is showing -20 on the PT meters in RMS mode before going further?

I need to get this right as I also have external Metering I need to align with PT outs that agree with whats going on in the box....

[joachim]

To my understanding, pink noise is used to calibrate speakers, not interfaces.
Pink noise -20 dbfs peak shows -20 dbfs on a peak meter within PT.
Pink noise -20 dbfs RMS shows -20 dbfs on an RMS meter within PT (Signal Generator on a mono track routed to a 5.1 aux with the Surround Scope (PT10) there set to RMS).

[PT user]

Hi
Thank you for your post and info

This is all about speaker calibration.... Everything I have read still wants -20db out of PT.

[joachim]

No.
Speaker calibration is about getting a certain sound pressure level measured with an RTA or SPL meter (e.g. 85 db spl , Leq C weighted , slow) out of your speakers when playing back a -20 dbfs RMS pink noise within PT, that measures of course -20 dbfs on an RMS meter within PT, at a to be adjusted output of an amplifier.

[TVPostSound]

Originally Posted by PT user

Im trying to calibrate my Avid Omni for 5.1.
Most things Im reading say start with pink noise RMS. Using Signal Generator and selecting a 1khz tone or Pink Noise comes up at -20dbfs on the meters as well as the plug in when SG is set to peak (default) . If I select RMS it obviously no longer correlates to - 20 on the meters within PT.

Should i be adjusting the plug in so it is showing -20 on the PT meters in RMS mode before going further?

I need to get this right as I also have external Metering I need to align with PT outs that agree with whats going on in the box....

Use these, and don't worry about internal meters.

http://abluesky.com/support/blue-sky...on-test-files/

[MIKEROPHONICS]

The Omni Analogue outputs are not calibrateable - unlike the 192 there are no analogue output adjusters

[TVPostSound]

Originally Posted by MIKEROPHONICS

The Omni Analogue outputs are not calibrateable - unlike the 192 there are no analogue output adjusters

Hmmm???

Mine do!! It's in the Omni submenu!!

Read page 51 in the manual!

[MIKEROPHONICS]

Please be so kind as to elaborate.... I sadly think I have a hole in my knowledge here

[reichman]

Also, take a look at ATSC A/85:

http://www.atsc.org/cms/standards/A_85-2013.pdf

Pages 36 and 37 have links to download audio file for calibration. Even if you don't read all of A/85 (I did), the quick reference section for mixers is invaluable.

Good luck.

[tamasdragon]

Originally Posted by MIKEROPHONICS

Please be so kind as to elaborate.... I sadly think I have a hole in my knowledge here

AFAIK the Omni has a SPL Cal mode, where you can trim the outputs. I don't have the unit, but seen something like this.
Oh, just found it in its pdf file:

"Analog Output Trim (OUTRIM)
In SETUP mode, the Analog Output Trim (OUTRIM) control lets you set the Analog Output Trim for each of the eight available analog outputs from –40 dB to +10 dB in 0.1 dB increments."