SONAR clipping at playback - curious problem

K

KarnEvil

New member
Ok.. I record a guitar track into SONAR as hot as I can without clipping (no little red square lighting up by the track meter). I playback the same track with all faders set to 0.0dB, and it clips according to the "light". However, I do not hear the clip and the recorded waveform does not appear to be clipped.

I would like to output EXACTLY what I recorded with no attenuation or gain at all. I figured the faders set to 0.0dB would achieve this for me - but, I don't understand why the clip light happens at playback when no clipping happened during recording.

Anyone experience this? Is this just a built in headroom margin or something?

Thanks
Karn
 
hmmm, well guessing outright... the instrument input levels are controlled by your soundcard, in case you haven't already checked this look at your input levels on your soundcard's mixer first to make sure you're not overdriving the input. Similarly, look at the master outputs for the card to check everything's ok.

cakewalk9 used to have an audio option checkbox to automatically limit and prevent clipping on playback... don't see it in Sonar anymore. Maybe still lives in an .ini file somewhere?

the waveform may appear to sit comfortably inside the range of the window, but is there any clipping data actually present at the peaks? If you put a limiter on the track set to 0db brickwall, does it still sound clipped?

just random thoughts...
 
I have a Darla24 soundcard, and I have learned that the rec/playback meters in Darla and the rec/playback meters in Cakewalk Pro 9 dont match up at all.

Karn9, I have the same problems you have, but I have PA9. My conclusion is that the meters in the program are highly inaccurate. It sucks, but I am learning to use my eyes and my ears, and then forgetting my eyes and just using my ears, because when I record, everything is perfect, then I hear clipping upon playback.

I try to monitor levels with Darla24, but they dont seem accurate either.
 
are you using peak or RMS?

in sonar you can choose view peak, RMS or both. if you use RMS then you aren't getting the absolute peak of a signal so you won't see necessarily see clipping even though there was clipping. conversely on playback the algorithm that determines the RMA level may show a peak.

when i record and playback i display both the peak and RMS levels. This way I visually see the difference between my peak signal and the average level of my signals, which helps me to set my compression and limiting ratios appropriately when mixing. this feature in sonar has really increase the apparent volume of my mix.
 
My little test

Thanks for the responses...

I did some playing around. I switched my test instrument to vocals (uncompressed) to get more sproatic amplitudes. Here's what I did (trying to be clear as possible):

1. I recorded a passage as hot as possible without peaking the track meter (or the inputs - I checked my Delta 1010 control panel). Looking at the waveform, I do not see any clipping.

2. With the trim and volume faders set to 0.0dB and playback meter set to 'post fader' and 'peak', I played the track back. I get clipping on the track meter.

3. Now with trim and volume still at 0.0dB, I switch the playback meter to 'pre fader' and 'peak', I played the track again. NO clipping on the track meter. Interesting, ehh? (I urge you to try to re-create this on your setups - make sure I'm not going insane.)

More info - No plug-in FX are being used - No envelopes - Just a plain, dry vocal recording.

Ok, now I test whether the output is actually clipping (or was the clipping meter just lying to me).

I happen to have another computer with Wavelab and an Audiophile2496 S/PDIF input sitting next to me. I connect a S/PDIF out from my Delta 1010 to this other computer and route the vocal track output to it. Now, I do the following using the same vocal track:

With trim and volume faders set to 0.0dB, I record the track onto Wavelab through the S/PDIF connection (no loss or gain in signal transfer). making sure the 2496 volumes are at 0dB. Result? I clip in Wavelab! Remember, this is the same track that did not clip while recording in Sonar.

Further testing reveals that Sonar gained this track by +3.0dB when faders are set to 0.0dB. I did this by comparing peak levels in Wavelab.

I am not ruling out the possibility of some setting within Sonar being overlooked by me. However, it does seem strange that this occurs in any case. My goal is to playback exactly what I record, down to the sample amplitude. This should be doable in the digital domain. I'm I missing something trivial here?

Thanks
Karn
 
You must log in or register to reply here.
Back
Top