clipping irregularity

hi=)

it seems that there is some irregularity between the channel, the master bus, the analysis and the metering…

here is a pic…

it is a normalized audio to -1db
channel doesnt clip
master clips
analysis shows this, metering shows that…

can anybody explain please?

thx =)

p.s. bigger and downloadable attachment pic for better quality for your consideration


Hi,

What numbers you don’t like exactly?

Are you avare about the fact, there is a Peak meassurement on the channels, and a Loudness meassurement in the Control Room/Meter?

Hi martin:)

The thing that worries me, which lead to this post, was that my master channel is triggering the red clip light.

Upon investigating further, it worried me that the loudness meter showed a true peak value of 0.1 db while the audio was normalized to -1db (like how the analysis correctly shows)
-is true peak in analysis and loudness meter different?

The audio channel playing does not clip red, but the master channel does.
The audio track is the only track active. (The channel to the left and not in the picture is a muted input)

Greetings and thanks for any insight:)

The True Peak is a calculated value which is intended to emulate the actual swing of the audio in the analogue domain (after D/A conversion). In the analogue domain the signal obviously follows the sample heights but only at the sample positions. Between the samples it can go elsewhere, it can swing above or below both adjacent sample heights. And when it extends beyond the highest/lowest sample then it represents the True Peak, which is obviously greater than the digital peak (which is calculated in the statistics window). Here’s a discussion:

Of course, then next question is what we’re supposed to do with this knowledge! I personally have taken to reducing my final mastering Waves L2 plugin to -1dB and then glancing occasionally at (i.e. largely ignoring!) the true peak meter…

I have heard it said that the true peaks will distort on cheap dodgy D/A converters which don’t have enough headroom. Also some mention of effecting MP3s, but I’ve not really followed up on this to see concrete evidence so I may be spreading urban myths :slight_smile:

Mike.

(Urban mythology questions): One tends to ask if we can somehow influence the swings between the samples… And- do these swings influence us somehow? If the music is between the sounds n all!? :stuck_out_tongue:

Thx for your input, dear mike:) - im off to read that tope blog right quick…

→ still, who can answer the red light clipping question dilemma?:stuck_out_tongue:

Take care, buds:)

Edit Ooh, interesting read, mike n tope! Havent gotten through the whole thing yet, but i suspect that the red clipping could have been caused because (maybe) cubase meters are reading analog ripples? Hmm…
(Cubase channels read sample peak and the masterbus reads true peak)?!?
Im off to read more:p

Hi ggc,

did you ever find answers to your questions??? I am about to discover weard stuff to that topic in cubase 10 pro. The meters don’t show what the audio statistics show. Until now I was fine with this, so I took it for granted, but now I am finishing a mix which is showing in the output metering a peak level -0.5dBFS and also -0.5dBTP, but the ‘printed’ audio is peaking @ 0.0dBFS and the true peak +0.04dBTP (checking the audio via ‘statistics’)… :question:

If that wasn’t enough, if I listen to the actual ‘mix’ with all channels playing out, print it (I mean downmix) , put it back into a channel in the same session, the downmixed audio in the channel is ±0.4dB lower in level than the actual ‘mix’ coming out of the masterbus or stereooutput.

I’m really confused now…

Hi defuuss, it’s best to raise this in the Cb10 forum then it’ll attract loads of new interest. Put a reference to this thread in too if you like.

I looked at it on Cb10.5 and it does seem strange. For a short sample these are my findings:

Statistics function said -0.25 True Peak, -14.7 Integrated LUFS
Master Meter said 0dB True Peak
Loudness Meter said 0dB True Peak, -11.3 Integrated LUFS
YouLean plugin said 0.1dB True Peak, -11.4 Integrated LUFS
Waves WLM said 0dB True Peak, -11.6 Integrated LUFS
MLoudness Analyser said 0dB True Peak, -11.4 Integrated LUFS

I don’t know why the statistics is off but all the others agree pretty much.

Mike.