Help with Pro Tools Clipping!

[JonCraig]

check somewhere in your preferences for metering options. if memory serves, on HD systems there are multiple ways to define just where your meters turn what colors. perhaps this is set to something wacky?

--jon

[tho_dk]

hi there...
Make sure that you have selected a stereo output if the files are stereo.
I think (also just from memory) that if you select a mono output for a stereo file it can clip because youre adding the sound of two files and so the sum of them might cause clipping even though each one one their own wouldn't...

best of luck!

Thomas

[OKden]

Our friends at the Answerbase offer this explanation.

[JonCraig]

i'm sure you've checked it, but sometimes the simple things are the ones that bite us in the ass... if your meters are post-fader, and you have that track's fader bumped up, you'll see clipping that way. just trying to make sure all the bases have been covered.

--jon

[Riccardo]

Thanks guys but it it a bit more "serious" (figuratively of course!) than that.
First because it is not only a matter of translation between LE and HD.

As an example if I pick a stereo CD track which is not clipped (a rarity I know ) and import into a session with no plugs at all it will play with overs in TDM (non only showing on the meters but also showing overs on the AES output with an external digital meter).
It plays fine il LE both Mbox and 002.

We also tried to import same tracks from different drives (i.e. internal, external Teac, Plextor ans so on...)

[Harley-OIART]

Is your meter calibration been altered somewhere in HD Software? Granted it has been about a year since I was in the studio with an HD rig, but I know my LE 002R rig inside and out, I'm sure you cannot alter any of the calibrations, meters, or number of consecutive clipped samples required to issue an Over ; in LE.

Sorry wish I could be more help, but it sounds like solution is a minor tweak setting somewhere in the HD Software.

Of course there is always the possibility that LE Meters are just plain innacurate.

Id love to know what you discover the solution is for my future reference.

Happy Hunting,
Scott

[Riccardo]

Well, I believe LE is fine.

Even - and I doubt - it was a meter calibration anomaly it still shouldn't output an "over" signal out of the AES/EBU (checked with external meter). The files we used do not go over 0 dBFs for sure. It is not only showing red on the meters but outputting it!

I have also dicovered some other "tasty things in the meantime" as in other things which behave dodgily....maybe that's what you get if you use PT

[blackcatdigi]

Originally Posted by Riccardo

The files we used do not go over 0 dBFs for sure. It is not only showing red on the meters but outputting it!

Out of curiosity, what happens if you pull the fader down .01dB?

Have you tried any of the premastering/analysis plugs that are capable of showing finer resolution of peaks?

[JonCraig]

Originally Posted by Riccardo

maybe that's what you get if you use PT

does the same thing happen when importing into another daw?

--jon

[drew]

what about recontruction overs? maybe no one sample clipped but the material will when going through the D/A and the meter is showing that? just a guess.

[obostic]

Originally Posted by Riccardo

I have been called to friends studio to help but I have to admit I am a bit puzzled.

System is an HD running on a Dual 1.8 G5 with a Digi96.
When inporting some "loud files" mostly stereo files the playback shows clipping (meter goes into the red. Meter on 96 also shows red).

Files are not clipped at all, loud and some close to -1dBfs yes but that's all.

Imported same files plus random others as a test into a Powerbook running LE 6.9 with Mbox2 and Dual G5 running 6.4 on a 002r files plays fine no clipping.

Wiped the whole machine clean, reinstalled both 6.7 and also tried 6.9.1 HD files clip.
also (measured the output with a digital meter to confirm)

Anybody experienced similar problems?

Thanks for your help!

I've experienced this exporting from Sequoia/Samplitude into Protools. Protools apparently has less headroom than Sequoia/Samplitude.; I had to re-track all the drums at a lower level in order to import the tracks in Protools without clipping. Your problem may be similar because Protool LE is floating point and HD fix point; the difference in headroom may be your issue. For a test, try and normalize one track to -6 dBFS then export it to Protools HD and see if this resolves the clipping. Well, if does there is your answer.

[JonCraig]

Originally Posted by drew

what about recontruction overs? maybe no one sample clipped but the material will when going through the D/A and the meter is showing that? just a guess.

that's not the case if it's blazing the light in PT. PT's internal meters are not triggered by interface's output, but rather the files being read from the disk. (incidentally... this is the reason that it's so important to calibrate your converters accurately!)

plus, the original poster has said that he still shows overs when going out digitally to external meters. no d/a there.

--jon

[Riccardo]

Originally Posted by JonCraig

that's not the case if it's blazing the light in PT. PT's internal meters are not triggered by interface's output, but rather the files being read from the disk. (incidentally... this is the reason that it's so important to calibrate your converters accurately!)

plus, the original poster has said that he still shows overs when going out digitally to external meters. no d/a there.

--jon

Exactly! That's the weird thing. It does not happen with the same files on LE both on a Mbox2 or a 002r we used check what was happening. If we import the same files into any of the 2 (LE rigs) the are fine. Reopen the session on HD...clipping... Import same files directly ino HD (tried different readers..internal...teac...plextor premium..etc) it clips!

Yes if I take the fader down 1 to 4 (not 0.2 - 0.4!) dB (no depending on file it obviously goes away.
The files are fine.

The G5' drive has been reformatted, PT re-installed, no cure (tried 6.7 and 6.9)

This is something I (even more than my friend the owner of the rig) want to understand

[JonCraig]

Originally Posted by Riccardo

This is something I (even more than my friend the owner of the rig) want to understand

i think you should re-read the link that okden posted.

--jon

[Harley-OIART]

Sorry I don't have time to type (but just wanted to say)

Call Digidesign. They probably won't charge for assistance in your situation. (at least they shouldn't if they have any thread of customer assistance left.)

Regards,

-Scott

[Riccardo]

Originally Posted by Harley-OIART

Sorry I don't have time to type (but just wanted to say)

Call Digidesign. They probably won't charge for assistance in your situation. (at least they shouldn't if they have any thread of customer assistance left.)

Regards,

-Scott

Thanks we will

[Riccardo]

Originally Posted by JonCraig

i think you should re-read the link that okden posted.

--jon

Thanks Jon but I think you misread my posts. Or more likely , english not being my first language I didn't make myself clear.

It isn't a problem of swapping sessions between LE and HD, that's just a test we did out of curiosity. It is like: get a cd from your collection, import audio to track, no plugs nothing, in LE is fine in HD it isn't. There is no need to move sessions around it was just some tests we made to try and understand ...

[JonCraig]

Originally Posted by Riccardo

It isn't a problem of swapping sessions between LE and HD, that's just a test we did out of curiosity. It is like: get a cd from your collection, import audio to track, no plugs nothing, in LE is fine in HD it isn't. There is no need to move sessions around it was just some tests we made to try and understand ...

ah... my fault. i misread.

--jon

[Harley-OIART]

So Riccardo, Whats the Verdict?

-Scott

[quickkeylee]

Riccardo,
The problem is that HD systems (or should I say TDM) meters will clip the moment one full scale sample is reached. LE is designed differently. LE will clip if a number of fullscale samples are reached in a row. Hope this helps solve your mystery.

[Harley-OIART]

Originally Posted by quickkeylee

Riccardo,
The problem is that HD systems (or should I say TDM) meters will clip the moment one full scale sample is reached. LE is designed differently. LE will clip if a number of fullscale samples are reached in a row. Hope this helps solve your mystery.

Thank you for post =) Any Idea off hand how many consecutive samples to register an over in LE? (Not that I really should want to know, Its not like I can't find a masterimg grade meter for protools )

Just curious for a useless reference if happens to know. My guess would be 3? 5? samples F.S. for an over in LE?

Randomly,
Scott =)

[Riccardo]

Originally Posted by quickkeylee

Riccardo,
The problem is that HD systems (or should I say TDM) meters will clip the moment one full scale sample is reached. LE is designed differently. LE will clip if a number of fullscale samples are reached in a row. Hope this helps solve your mystery.

First of all thanks to all of you guys for the input, suggestions and so on.
Yes Quickkeylee that would be the most logical explanation.
Still I am not entirely happy that if I were to load a file that I know being below 0 dBfs it would show red on an HD system whereas on LE or on another DAW wouldn't.
My friends are having the cards/hardware checked and as soon as session scheduling permit we'll swap G5's just in case.

Still investigating.......

Did I tell you that on the same HD if you SRC down a file close - but absolutely NOT reaching - 0dBfs the resulting file is always clipped?
Moreover if you SRC and dither in one go (bounce to disk) the same file it doesn't clip!


Tell you what for music production PT is fine but for myself I am happy to stay on Sonic....

Still investigating.....