Metering Classic vs Sample Peak

[Darryl Ramm]

Originally Posted by bryced87

but distortion doesn't exist in the yellow. Also when I record below the yellow In pre and then move the fader up to raise the volume I hear noise. The only way to get rid of this when I turn up the fader is to record in the yellow.

"Noise" is not necesarilly related to digital clipping/distortion.

But you have been using a trim plugin, which is a completely useless way to try to do anything. So what does all this "record in the yellow" actusally mean? What happens when you get rid of the trim plugin and track properly with the preamp gain correctly used to set a correct converter input level? And what exact preamp and any other analog front-end gear into what exact interface? Recording what exactly? With what mic, DI etc? You are monitoring this dry or through what plugins while tracking?

If you are really using an Mbox 2 you don't have a high-end preamp or converter to start with, what exactly are you recording? Input levels I to the Preamp are important to understand, and where is the preamp gain knob set? And what are you monitoring through?

Maybe there is pre-amp distortion/analog noise that sweeten the sound or masks issues, or other electronics problem, or you are confusibg pre-amp analog/stage compression effects for reduced "noise". Work on some critical listening tests, systematically recording things at different levels (adjusting the preamp gain), then tweeking playback levels to match, multiple tracks in one session that you can switch between to compare. A common cause of claims like this are poor output level matching, especislly when combined with less than great monitors/room setup. Or it's imagination, get somebody to help you do a blind test with those tracks, or give them a blind test.

[bryced87]

Originally Posted by Darryl Ramm

"Noise" is not necesarilly related to digital clipping/distortion.

But you have been using a trim plugin, which is a completely useless way to try to do anything. So what does all this "record in the yellow" actusally mean? What happens when you get rid of the trim plugin and track properly with the preamp gain correctly used to set a correct converter input level? And what exact preamp and any other analog front-end gear into what exact interface? Recording what exactly? With what mic, DI etc? You are monitoring this dry or through what plugins while tracking?

If you are really using an Mbox 2 you don't have a high-end preamp or converter to start with, what exactly are you recording? Input levels I to the Preamp are important to understand, and where is the preamp gain knob set? And what are you monitoring through?

Maybe there is pre-amp distortion/analog noise that sweeten the sound or masks issues, or other electronics problem, or you are confusibg pre-amp analog/stage compression effects for reduced "noise". Work on some critical listening tests, systematically recording things at different levels (adjusting the preamp gain), then tweeking playback levels to match, multiple tracks in one session that you can switch between to compare. A common cause of claims like this are poor output level matching, especislly when combined with less than great monitors/room setup. Or it's imagination, get somebody to help you do a blind test with those tracks, or give them a blind test.

So what is the difference between the gain clip feature on the waveform vs the trim? I never use the trim till after I record. I have no plugins when I record anyway.

I have an Audio Technica AT2020 Large Diaphragm Condenser Mic. XLR plugged into my Mbox 2. Even with the input level on the Mbox2 set halfway I hardly see any level. It reaches -60 to -50 on the Pro Tools input. I don't even get the level at -10 until the Input on the Mbox2 is up all the way. Something seems wrong here. I have Phantom Power on as well. I've tried different XLR cables. I have even tried someone else's microphone which is a SE X1 Cardioid Condenser Mic. The input levels remain the same regardless of what XLR cables I have or Mic.

If I plug in an electric Guitar via the TRS inputs on the Mbox2 the level reaches above -10 with the input volume knob half way.

[Darryl Ramm]

Originally Posted by bryced87

So what is the difference between the gain clip feature on the waveform vs the trim? I never use the trim till after I record. I have no plugins when I record anyway.

For this discussion there is no difference, the question is not relevant, I am not going to follow you down whatever rat hole you are going. We have covered this earlier, but whatever you are doing with mix levels in the ultra-high-dynamic range mixer in Pro Tools is *irrelevant* to clipping (or input noise) related converter issues. Get your head out of digital toy-land and into analog land.

I have an Audio Technica AT2020 Large Diaphragm Condenser Mic. XLR plugged into my Mbox 2. Even with the input level on the Mbox2 set halfway I hardly see any level. It reaches -60 to -50 on the Pro Tools input. I don't even get the level at -10 until the Input on the Mbox2 is up all the way. Something seems wrong here. I have Phantom Power on as well. I've tried different XLR cables. I have even tried someone else's microphone which is a SE X1 Cardioid Condenser Mic. The input levels remain the same regardless of what XLR cables I have or Mic.

Well there is likely a large part of your problem. Check the input pad is not engaged, check the phantom power voltage with a multimeter, check your mic on a different preamp etc. Be careful that proper mic technique is being used.

If I plug in an electric Guitar via the TRS inputs on the Mbox2 the level reaches above -10 with the input volume knob half way.

Edit: (again, sorry I misread TRS as XLR) Where you need to set the input gain (again the analog knob on the MBox not in Pro Tools) depends on the guitar output level -- what exact pickups does it use?

[JFreak]

You need to understand both sides of the story, analog and digital.

Digital side is easy. As I already said, take a look at your AD converter spec and do the math. Having a 124dB dynamics means you don't gain anything if your peaks are higher than -20dBFS. Record higher than that and you are amplifying noise and sacrificing transient headroom. This is pure math, nobody can disagree.

Analog side, though, is more tricky. You need to know how to output a perfect analog signal to the AD converter. But that is not the discussion here. Just that whatever you feed to the converter determines the signal-to-noise ratio and therefore the amount of noise you're converting.

[JFreak]

(there is no such thing as perfect analog signal. meaning as good as it gets)

[Park Seward]

I worked with a Pro Tools engineer who would always record "hot". But that is a relative term. If he gave me a track for a video, it was too high since Digital Betacam's "0" level is -18dBs. He was recording in Pro Tools at around -3 so I would always have to lower his levels in order to match the operating level of a video recorder.

He would never clip, however. Reduce your levels so you don't "tickle the dragon"!

If you record a signal at -3 or -18, there is no difference in the sound. The only difference will be the noise floor. However at 24 bit, you'll never hear that noise floor.

"but distortion doesn't exist in the yellow. Also when I record below the yellow In pre and then move the fader up to raise the volume I hear noise. The only way to get rid of this when I turn up the fader is to record in the yellow."

I don't buy it. There is no added noise caused by recording at -18dBm. If you have a s/n ratio of 124db and reduce the level by -18 dBm, you have a s/n ratio of 106 db. You can't hear that. Perhaps your input source is noisy but recording hotter will not lessen a noisy input.

You can change the operating level in Preferences.

"The 0 dBFS setting determines the unity reference level for the meter scale in decibels compared to digital 0 dB. Exceeding this level should result in clipping at the digital to analog converters or to the specified clipping level for broadcast. "

You can adjust the color break point of your meters.

"Color Break Low
The Color Break Low setting determines the low point in dB where the color changes for metering. Typically, this will be the minimum level for the current Meter Type. Use this setting to provide a visual indication in the meters for the lowest level of the dynamic range of the program material for the intended delivery format (such as film, DVD, CD, MP3, or broadcast)."

[Chief Technician]

Originally Posted by Park Seward

I worked with a Pro Tools engineer who would always record "hot". But that is a relative term. If he gave me a track for a video, it was too high since Digital Betacam's "0" level is -18dBs.

Maybe in Europe. In the U.S., the typical analog calibration level of a Digital Betacam is -20dBFS.

Originally Posted by Park Seward

You can change the operating level in Preferences.

That's for interface I/O calibration purposes. The user has to have their interface calibrated to that level. Simply changing that level in preferences does not change the calibration level of an interface.

Originally Posted by Park Seward

"The 0 dBFS setting determines the unity reference level for the meter scale in decibels compared to digital 0 dB. Exceeding this level should result in clipping at the digital to analog converters or to the specified clipping level for broadcast. "

I am uncertain what point you are trying to make here. 0dBFS on a meter is full scale digital. Anything above that is clipped. Even if the audio in question does not reach 0dBFS, it is possible that the output is clipped. This is what oversampling meters such as the TLMasterMeter are for.

[Bob Olhsson]

Originally Posted by bryced87

Then why do tons of video tutorials say your recording levels should be in the yellow? Also Paul Draper from in the box series explains how you use the trim plugin in prefader to lower the input if you've recorded to hot.

They are parroting ignorant nonsense from the daze of 12 bit sampling keyboards when there weren't any tech writers who knew anything about digital audio.

My experience has been that the two most common causes of brittle "digital sound" are inadequately powered transistor analog stages even in expensive gear and the truncation distortion caused by failure to dither each and every bit reduction.

[Park Seward]

Originally Posted by Chief Technician

Maybe in Europe. In the U.S., the typical analog calibration level of a Digital Betacam is -20dBFS.

You are right, Jonathan. Doesn't pay to rush. Sony reports it as 20db headroom.

Originally Posted by Chief Technician

That's for interface I/O calibration purposes. The user has to have their interface calibrated to that level. Simply changing that level in preferences does not change the calibration level of an interface.

Yes. Moving the yellow does nothing. Moving the peak level down does.

Originally Posted by Chief Technician

I am uncertain what point you are trying to make here. 0dBFS on a meter is full scale digital. Anything above that is clipped. Even if the audio in question does not reach 0dBFS, it is possible that the output is clipped. This is what oversampling meters such as the TLMasterMeter are for.

Simply saying that you will clip if you exceed 0 dBFS. Sorry if I wasn't clear.

[bryced87]

Wait. So I can record in the yellow or I can't?