clipping after applying effect?

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dobro

dobro

Well-known member
I'm using compression less often in the mix nowadays, which means that dealing with peaks is more of an issue. What I typically do is use a volume envelope on the peaks in multitrack to get levels where I like them. I often like the sound of the track better without compression.

Okay, but here's my question coming. If I get track levels where I like them and then take a track into Edit View and apply EQ or reverb or something, occasionally that shoots the levels up past the clip point. So, first of all, I'm right in thinking that those volume envelopes in multitrack have no effect whatsoever to the tracks in Edit View, right? And secondly and more importantly, it means the track's now got some distortion, right? The volume envelopes don't protect against that, do they?
 
Most likely it's playback distortion. I had a song where two of the vocal tracks had some EQ applied and it sounded great played back in CEP. When I burned a CD, however, there were a couple of places where the vocals distorted due to lower headroom in the playback system. I removed the EQ, burned a new CD, and the distortion was gone. CEP will tolerate pretty high signal levels before you actually have distortion on the track itself.

You probably already know this, but try subtractive EQ (taking away the frequencies you don't want emphasized) rather than additive EQ (boosting the desired frequencies).
 
"You probably already know this, but try subtractive EQ (taking away the frequencies you don't want emphasized) rather than additive EQ (boosting the desired frequencies)."

Yeah, I know about that. But sometimes you just have to boost LOL.

And then, I use a pretty bright reverb, and when I apply it to certain tracks, it really changes the shape of the waveform, and sometimes that change involves the peaks going too high like I described.

But I'm really interested in the thing you described - the thing where Cool doesn't playback a track distorted, but when you burn it to CD, you hear distortion.

First question: where's the clip line in Edit View exactly? Is it the horizontal line, or is it the limit of the screen?

Next question: if you've got a track that clips and you apply compression or hard limiting to it, will that lop off the distorted portion of the track? In other words, does the distortion only arise out of the portion of the peak that goes beyond the clip line?
 
Dobro, the blue lines are at a nominal -3dB. I say nominal, because I have had mixdowns go into the red over that (where the extreme top & bottom were not visible), and then have used amplitude to lower the overall level, and found no distortion or clipping. [Adobe Audition allows you to change the format of the vertical axis but I don't know if CEP will do that. I couldn't find anything on it.]

So, nominal 0dB is apparently not clipping. Whether this depends on your particular setup I don't know. In the situation I was speaking of, the EQ'd vocals were NOT clipping, and NOT audibly distorting on playback through my 350WRMS/Channel playback system. But once I burned a CD, and loaded it into the little stereo playback setup I keep in the studio, there were 2 places in the song where there was noticeable distortion. It took me a week to track down the culprit, since there was no meter indication of overload. When at last I removed the EQ boosts, and burned a CD, the distortion disappeared. This made me a believer in subtractive EQ!

Compression (or hard limiting) will only compress what's there. If you are compressing distortion it will remain...but the sound may improve as a result. About the only time I record with distortion is when I am trying out a new hot mic. I use a digital mixer to control levels and generally manage to avoid any clipping.
 
I didn't read past your question, so I may repeat.

You can clip something in edit view with EQ that's not clipping in the multitrack with the same EQ on it, DEPENDING ON WHAT YOU'VE DONE WITH THE MASTER FADER.

See,you can EQ the snot out of a track in a particular frequency in the multitrack, and if you have the master fader at 0, and you see the red lights come on when you're playing it back in multitrack, it's clipping. If you're like me, you turn the master fader down b/c you have several tracks going and you're really not sure which one is clipping, or if all of them are.
 
If you want to work out which control affects what, see http://www.morphet.org.uk/audio/cep.html for details.

Personally I'd only apply effects in edit view that I can't apply in multitrack view (eg noise reduction). Use 32 bits to give the 1500dB dynamic range, normalise the file after mixdown, and hey presto, no distortion.
 
Chris, it's not really clipping that I don't understand - I asked my question badly. What I'm wondering about is clipping that distorts - clipping when recording. I think Ozpeter answered my question in another thread, where he said that if the meter lights up in edit view, then it's clipping. I'm assuming that means it's distorting as well. See, if the distortion's mild, I have a hard time telling whether it's distortion or just loudness. So I'd like a visual cue. That's why what lpdeluxe mentioned is important to me - he talks about Cool Edit not indicating clipping (therefore, no distortion), but a burn of the session distorted. But I think he's talking about the same sort of clipping that you're talking about - overall session level which is too loud.

So, my understanding is this: the track that's playing in Edit View is in its original state in terms of level. And if the red meter lights up, that means that not only is it clipping, but it's distorting as well. Plus, there's nothing I can do to get rid of the distortion. I can't 'undistort' distortion once it's there. Yes?
 
Hey Oz -

"Personally I'd only apply effects in edit view that I can't apply in multitrack view (eg noise reduction)."

How come?

My thinking's been along the lines of: permanent editing coupled with backups is a more reliable situation than relying on the .ini file in Cool Edit - I may or may not have remembered to back up the .ini file.
 
dobro said:
So, my understanding is this: the track that's playing in Edit View is in its original state in terms of level. And if the red meter lights up, that means that not only is it clipping, but it's distorting as well. Plus, there's nothing I can do to get rid of the distortion. I can't 'undistort' distortion once it's there. Yes?
Click to expand...
Not necessarily, lol.

2 things. First, hitting the red just means "0db", it doesn't NECESSARILY mean that it clipped. It may have gone over, it may not have. Only your ears can tell you whether it did or not. If you don't hear digital pops or distortion, it probably didn't really clip. Secondly, CEP's meters are set a little hotter than real life. Last time I checked, they're about -.3db hotter than reality. In other words, stuff that REALLY is at -.2db may show up as a "clip" in CEP even though it didn't really hit 0db in "real life," lol. It's like an idiot meter. I usually try to never let anything go hotter than -.3 in CEP, which in reality is closer to -.6db.

Now, you're right about the fact that once you've clipped it going in (i.e., recording), you can't UN-clip it. I mean, there are tools in CEP that claim to restore clipped material, but the only time I'd ever even try something like that is if the person that recorded the clipped material is dead...otherwise, re-do it, ferfuxache :D
 
Clipping and distortion don't necessarily go hand in hand, as far as the ear hears anyway - a couple of clipped samples could flash by unnoticed. A handful you'd hear. If you are in a position to use vst effects, there's the "inspector" freeware vst which incorporates alarms and clipped sample counters.

I guess working practices vary with context, but working non-destructively seems safest to me, even though one ends up with an original file and an edited file. Storage is cheap, time isn't - and what sounds great at 11pm can sound pretty naff at 9am the next day.
 
"I guess working practices vary with context, but working non-destructively seems safest to me, even though one ends up with an original file and an edited file. Storage is cheap, time isn't - and what sounds great at 11pm can sound pretty naff at 9am the next day."

Yes, fair enough - it would save me loads of time. It just means making the backing up of the .ini file part of every save. BTW, if anybody else is reading this and using it, it also means backing up the .ini files for my plugins, which is located in a different place. I once thought I was backing up all my settings by backing up the cool.ini file, and then had my plugin settins wiped out in a reinstall. Pooh.

BTW, what's the coolacm.ini file? Mine's empty, so it's no biggie, but I asked this before I think, but I don't remember seeing an answer - I missed it if there was one.
 
me too i dont like how my vocals usually sound after compression if i have a track with alot of variation in its dynamic range i dont see any problem with it.. ill just usually add the hard limiter to my vocals to soften the high frequencies
 
The hard limiter doesn't affect frequencies - it knocks the tops off the loudest peaks.
 
Indeed - I had cause yesterday to test its operation and demonstrated that the hard limiter has no effect on your sound apart from reducing the level of peaks that would otherwise clip. Whether some might percieve that as softening the sound is a more subjective matter, however.
 
Okay, I think I've figured this out. If anybody sees anything wrong with my approach, please let me know.

I record a track without clipping. Nice. I apply an effect, but now it clips. Okay, so what do I do? Undo the effect and go back to the original track. Apply volume envelopes to the peaks. And now... wait for it... make a mono mixdown of the track with the volume envelopes. Insert the new track into Multitrack. And with the new track which now has much lower peaks, apply the effect and see how it doesn't clip anymore.

Have I got this right?
 
I find myself saying "You what??" :)

It's difficult to comment on your approach because you have your own reasons for following it, which I don't fully understand - as far as I am aware, a session file contains everything needed for the session, I just don't see where you concern about .ini files comes in to it - but compared with the conventional way of working, what you've outlined is awfully like hard work, and really wastes at least 50% of the utility of the program.

It's hard to say that without sounding rather rude, but I trust you will take the comment in the spirit of one genuinely seeking to point you in what I personally feel is a much better direction!

Also, without checking in detail, but off the top of my head, most effects that would inadvertantly have an effect on levels in fact have level controls built in, so you should be able to nail the problem at source in any event.
 
I'll chime in here just to say, recording at 24 bits, I try to get my recorded signals peaking around -12/-8 db, there is so much dynamic range at 24 bits there's really no need to be removing all of the headroom right at the beginning of the recording process.

Just my 2 cents.. :)
 
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No, no, you're not being rude. I just don't get it.

"as far as I am aware, a session file contains everything needed for the session, I just don't see where you concern about .ini files comes in to it"

The .ini files contain all the information about the settings I use for EQ and reverb on a particular session. I don't write that stuff down in books - I save it in Cool Edit. If the program crashes, I lose all that information. So I have to back up the .ini file for every session I mix.


"...compared with the conventional way of working, what you've outlined is awfully like hard work, and really wastes at least 50% of the utility of the program."

Well, that's what I was asking - is there an easier way?

"Also, without checking in detail, but off the top of my head, most effects that would inadvertantly have an effect on levels in fact have level controls built in, so you should be able to nail the problem at source in any event."

If that's the case, then why, after I apply some EQ and reverb to a track in Edit View, does the waveform sometimes expand and shoot up so that the peaks go off the screen, and the clip light comes on when I play the track in Edit View?
 
Ah, okay, I've answered the last question myself - I adjust the output gain of the effect so that the peaks don't clip.

Okay, now how about question 2? :)
 
Okay, I've answered that one too. I refer to my answer for question 3. lol

I'm just gonna do everything in multitrack from now on. I've been using 2.1 mostly as if it were 1.2 just out of habit.

I'm still gonna hafta back up the .ini file though. No?
 
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