Topic: SBD ran HOT (Clipping), how can i try to repair?

[Chimney Top]

Last night i recorded a great show.  The SBD portion ran extremely hot for most of the show, i had my levels set to -45db and it was stlll blasting... finally turned down the output on the sbd.  however. i have several songs that need repair.  will anything work?  I am getting distortion on the bass throughout most of these songs.  since i am making a matrix i have the room mic's to help if i have to do anything drastic.

Thank you!

i use logic 9.

[LikeASong]

I'm sure that other (more experienced) tapers could chime in, but I'll give you the few knowledge I have about this.

Recordings that ended up being distorted/too hot/clipping are NOT fixable. Those spots where the audio clips are fragments of sound that reached the maximum input that your recorded can handle, and therefore they're not correctly readable anymore, or fixable in any way. You can try to do white-noise reduction, volume normalizations, etc but all that stuff ends up being quite useless since the distorted spot is going to remain there no matter what you do. It's sad but we have to deal with the fact.

Doing an analogy which is pretty easy to understand,  let's assume you have a mic/recorder that can handle '10' as it maximum volume.

If the sound source you're providing to it goes like..:  2, 4, 12, 3, 17, 11, 6, 10, 9, 14, 15, 8, 11, 12, 14, 8
The volume you'll be recording will be something like: 2, 4, 10, 3, 10, 10, 6, 10, 9, 10, 10, 8, 10, 10, 10, 8

The spots where there's a 10 are the spots where it's distorting because the input is too loud for your recorder to handle it. The recorder saved them all as 10's and that's why they aren't recoverable (there's no way to know if that 10 actually belongs to a 12, 13 or 17).

I think that's pretty easy to understand.


I'm sorry for the part of your recording that came too hot, maybe you can simply run a bass&noise filter in those songs, and fix the sound by patching a higher % of the other recording? Good luck

[page]

Recordings that ended up being distorted/too hot/clipping are NOT fixable.

maybe you can simply run a bass&noise filter in those songs

basically yeah. I've had some luck with all sorts of pro plugins, but I've never gotten a clip restoration plugin to work on a live recording to any satisfaction.

If it's just the bass that distorts for songs, have you tried EQing the other source so it's bass heavy and then running a HPF on the sbd recording?

[Todd R]

If you have distortion because you've had input or output analog "brickwalling", then you're pretty much screwed.

If the issue is digital clipping by trying to go above 0dbFS (the maximum for digital), I've had pretty good luck using clip restoration plugins or software.  At least that is if you're only talking about 1-3db clipping, which usually is quick snare transients or whatever.  If you've clipped 4-5db or more, then even clip restoration probably won't work too well.

I used to use clip restoration in the old Cooledit, whatever that is called now.  Lately, I try to just avoid any digital clipping, but when mastering old shows from back when I was an idiot and let it happen, I've been using Audacity.  I don't know if it came with Audacity or if I found it separately, but there is a free clipfix.ny plugin that I use.  It seems to do a decent job of repairing digital clips, again if they are only 1-3db in magnitude.

[Chimney Top]

In response to all the posts:

I really haven't learned too much on how to use filters with this software, yet...

it sounds like my only option/hope is to run low frequency filter and then use more AUD source.


HPF = high pass filter?  it sounds like it is just the bass, everything else sounds fine...


Thanks ya'll

[bonghitwillie]

if it only clips occisionally, you can use sound forge or cool edit and blow out/expand the wave form and lower each clipped area manually. i have not done this in years, but it worked for minor clipping where you heard distortion occaisionally. give it a try. plus once you get going i think you can somehow automatically find the problem areas and fix them faster, like find, copy, paste.

[Drgiggles1]

You can try the declipping tool in iZotope if it's severe clipping. I was able to at least get a representative copy of a show with that tool that normally I would have trashed. However you may introduce digital clicks, like I did, therefore, afterwards I used Adobe Audition to zoom in on all the obvious peaks and knock them down. Afterwards I ran the declicking tool using the digital clipping preset setting in iZotope. In the declipping portion you will need to play with the settings till you get your desired levels and result. It will definately take some patience and days of work. But in the end it may be worth it. At least for me it turned out pretty good. Was unnoticeable through head phones.

[One Cylinder]

Todd R pretty much summed it up. If the signal is distorted before it even reaches your recorder, there's nothing you can do.  It blows, but on the bright side, at least the clipping  wasn't your fault!      

If the signal coming into your deck was clean (not clipped,) and the clipping is a result of your levels being set too high, then you can likely repair the clipped portions via digital editing software. I've found Cool Edit Pro to work well for this. I'm sure newer/more current software has clip restoration feature(s) as well.

[capnhook]

Add my vote to clipfix.ny

Works great....

[leehookem]

Izotope RX can help.

[Walstib62]

Try using a high pass filter. That may eliminate the clipping if only the low freq. 's are affected. I wouldn't go load 4 or 5 different software packages to fix clipping, unless you expect to be doing this routinely.

[OldNeumanntapr]

Next time you plug into the board try using inline pads. They will help a lot. My Tascam DA-P1, being a pro deck, will take a high level signal into the XLR inputs without clipping. I use to use a Sony D7 and got clipping when I plugged in.

[Chimney Top]

bump...

tonight I ran 4 channels (aud and sbd)... the left channel sbd was hot, clipping in the mid-range... female vocals and some fiddle most notably.

I use logic and i have audacity installed.

aside from what has already been mentioned (I've looked at some of the programs - not sure if they work with mac), anything you can use to repair the light mid-range clipping?