true reference monitoring in Pro Tools 12.7

[Isadore]

hi folks, I hope my question isn't too cryptic. I'm running PT 12.7 with an Apollo 8 Duet interface (plus an external Millenia preamp). I'm working remotely with an engineer who is mixing some sessions and returning them via dropbox. When I import the mixed WAV file into my session, it distorts. (BTW the mixed wav file volume is set to -db). He said it is an issue on my end, and asked if my system is set to -14db or +4 db? How does one go about diagnosing that and re-setting it if need be? He referred to it as "true reference monitoring." Thanks for your time.
Also I also running an older Mac mini.

[BScout]

Most likely your guy asked "reference level" which is a term in audio. not "true reference monitoring" which is not an established thing.

Reference level is usually either -10dBV or +4dBu. (not 14 anything)
The Apollo 8 has selectable settings for input between the two options.

Output to speakers is not based on that because output level is variable (why we have volume knobs). But your speakers will have a setting for what reference level they are expecting.
(The Apollo seems to be calibrated to +4dBu output variable to +20.2dBu; which is standard for professional equipment)

The basic thing is: do these files clip on the meters in Pro Tools? If they do, then none of this other stuff matters. The files are clipped. If they do not, then just turn down your volume knob and make sure your speakers are set correctly.

None of this has to do with Pro Tools but the analogue domain hardware (speakers, volume, audio interface). Digital is digital -- those 0/1 bits are the same at your engineer's place as in your Pro Tools session.

[Darryl Ramm]

^^^ all good stuff.

You don't mention what monitors you are using, in addition to some monitors having settings for +4 dBu or -10 dbV line level inputs some may have variable input levels that you just have turned up too far. And folks can run into problems if trying to drive say a consumer amplifier and speakers that are expecting -10 dbV line level.

You might want to calibrate your monitoring setup, that delivers a nominal SPL loudness for a certain digital signal level. There are multiple advantages in doing that, and doing that setup carefully can be a good learning experience. Even might help find errors like +4dBu professional level outputs driving inputs expecting (or set to) expect consumer level -10dBV line input, or might help demonstrate if monitors are under powered etc.

You can find lots of writeup online on what +4 dBu and -10 dBV reference levels etc. are all about. And good instructions for calibrating your monitors are here https://www.soundonsound.com/techniq...itoring-levels,

[Isadore]

The PT session doesn't clip. I kept the master volume around -5db, but when I get them back from the engineer, the volume level is correctly set to 0db but they will then clip. My monitors are older Maudio and I don't see what db they are set on, maybe I should research that.The engineer brought that up also. Thanks for the link to re-calibrate, I think that might be the problem.
I apologize for mistakenly posted on the version 11 thread.

[Darryl Ramm]

Originally Posted by Isadore

The PT session doesn't clip. I kept the master volume around -5db, but when I get them back from the engineer, the volume level is correctly set to 0db but they will then clip. My monitors are older Maudio and I don't see what db they are set on, maybe I should research that.The engineer brought that up also. Thanks for the link to re-calibrate, I think that might be the problem.
I apologize for mistakenly posted on the version 11 thread.

You are talking about digital clipping? i.e. just import the wave files into Pro Tools and play them back... watch the track meter that file is on. if the clip meter does not go off at 0dbFS it is not clipping. Set Pro Tools in classic meter mode and track is in pre-fader metering or the fader is at 0dB. Make sure 0dB on the meter is set to 0dBFS in the Setup>Preferences. if that shows it's clipping you talk to the mixing engineer, it's not a debate. If it does not show clipping then the problem is on your side.

Being pedantic... but extreme clarity here helps when you are talking to others. Master volume? You mean Master fader? -5dB is a level not a volume. Personally I would not use the master fader to avoid output clipping (including because I don't want to use final stage plugins on the master fader. I'd want to control the level earlier in the mix. "volume level set to 0db"? you mean the Master Fader is set to 0dB?

[Isadore]

I'm sorry to not be clearer with my question. Is there a fairly simple answer as to how to see if your Pro Tools is sending a +4db or a -10 db to the monitors?

[JFreak]

Originally Posted by Isadore

I'm sorry to not be clearer with my question. Is there a fairly simple answer as to how to see if your Pro Tools is sending a +4db or a -10 db to the monitors?

Stick voltmeter to the outputs. 100% reliable method.

[its2loud]

Originally Posted by Isadore

I'm sorry to not be clearer with my question. Is there a fairly simple answer as to how to see if your Pro Tools is sending a +4db or a -10 db to the monitors?

Without using a meter, if you're connecting to your speakers with a consumer phono or rca cable then chances are good that the output of your interface or computer is -10. If you are using balanced 1/4 or xls cables to your monitors then chances are good you're at +4. This is not fool proof but it's a good place to start. Either way, there's no substitute for proper calibration.

There are plenty of SPL meter apps for your phone. Not 100% accurate but will get you in the ball park of where your monitors should be set.

[Darryl Ramm]

Originally Posted by Isadore

I'm sorry to not be clearer with my question. Is there a fairly simple answer as to how to see if your Pro Tools is sending a +4db or a -10 db to the monitors?

+4dBu or -10dBV.

Pro Tools does not know or care about this. Its the behavior of the interface hardware. BScout already described what the Apollo 8 has/does. It's variable monitor control output lets you drive up to 20.2 dBu. Its unclear what MAudio monitors you have, but they are not the most capable monitors, if you are driving your monitors hot it will not be surprising if they distort/sound awful. So just turn the output level on the Apollo monitor control down, and/or turn any sensitivity knob on the monitors down as well (and/or if it has a line level switch set it to -4dBu. You play with that gain staging to get the best result (using your ears). You have no metering in Pro Tools or the Apollo hardware that shows you the actual analog levels going out to the monitors, even the Apollo 8 LED meters are pre-final monitor level control. An external multimeter can be handy but you gain stage the interface and monitors by listening. If you go through monitor level calibration with low-end monitors you are likely to find they cannot meet typical target SPL levels without distortion.

I assume you are asking about this because the file from the mix engineer shows no digital clipping?

[BScout]

What Darryl said.

Originally Posted by Isadore

how to see if your Pro Tools is sending a +4db or a -10 db to the monitors?

To be clear, Pro Tools doesn't send any of this. The audio hardware is the one that sends a level (it takes that digital signal from Pro Tools and converts it to analogue volts that go to your speaker.)
The hardware is responsible not the software.