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-   -   Need urgent solution to fix sound (https://www.dvinfo.net/forum/all-things-audio/111045-need-urgent-solution-fix-sound.html)

Jose Milan December 27th, 2007 03:41 PM

Hello,

It got better, but we need to get rid of the background noise to be able to sell the proyect.

Other thing is that I really dont know much about audio postproduction, I only now how to volume things up or down, noise reduction (getting a clean sample) and not much more.

All the little filters, parameters and other methods I do not know how to aply, thats why I asked a step by step solution better with Cool Edit Pro if possible or in the software mention before, but with a step by step procedure because this is a total new world for me.

But I can wait for this a little...I would like to hear a cleaner sample so hear from myself to see if is possible to eliminate the remaining background noise (is it???)...of course only if you are willing to do so, I don't have any more hope.

I'm trying to send a longer clip at this moment.

Thanks

Steve House December 27th, 2007 04:00 PM

Quote:

Originally Posted by Jose Milan (Post 798909)
Hello,

It got better, but we need to get rid of the background noise to be able to sell the proyect.

Other thing is that I really dont know much about audio postproduction, I only now how to volume things up or down, noise reduction (getting a clean sample) and not much more.

All the little filters, parameters and other methods I do not know how to aply, thats why I asked a step by step solution better with Cool Edit Pro if possible or in the software mention before, but with a step by step procedure because this is a total new world for me.

But I can wait for this a little...I would like to hear a cleaner sample so hear from myself to see if is possible to eliminate the remaining background noise (is it???)...of course only if you are willing to do so, I don't have any more hope.

I'm trying to send a longer clip at this moment.

Thanks

Jose, it may be possible to make it 'better' but it might not be possible to eliminate it altogether. Only you can judge how good it has to be to be acceptable. Have you considered looping the presenter's lines - re-recording them in lip sync in studio? If perfect sound is required that may be your only option. As far as step-by-step directions, it might not be that simple. Because of the variable nature of the noise you're going to have to go through the entire clip bit by bit and different parts of the material might require different settings of the equalization, noise reduction, etc. Folks here may be able to offer suggestions on things you can try but other than cleaning up the entire track for you (and an offer of compensation to them would be appropriate if they did) it's going to be very hard for anyone to give you a step-by-step cookbook solution for you to follow from beginning to end.

Dave Blackhurst December 27th, 2007 04:34 PM

OK, is it me or do I hear a delay of the audio track?? It almost sounds like the speaker is speaking, and then there is a delayed "echo"... or is someone else speaking over him?

If it's an "echo", perhaps using phase cancellation of the original track with an offset? Not sure how much damage this woudl do to the primary track, but thought this observation might help suss out the problem... it's not just noise, but almost like a second delayed track to my ear.

Jose Milan December 27th, 2007 05:32 PM

Hello again,

Steve: For us usable sound is one without the background noise, the sssh sound.

We can not take the spokeperson to dub over in studio, this was a course with many people and he is not a professional dubber, no way his going to do 10 hours of dubbing. Thats way our only chance is to make the sound as good as possible and see if we can sell the product.

Dave: I cant hear the echo you talking about, but once again I'm no expert at this. Can you give steps to use the filter (phase cancellation of the original track with an offset???) in Cool Edit?

Thanks.

Jose Milan December 27th, 2007 06:13 PM

To make things clear,

I dont expect anyone to fix the clips (its about 10 hours!!!), I just want it to know if is possible to fix, hear a clip that has been cleaned and know is possible and hopefully get some guidence on the steps or things to look for on how to fix it, Francois is doing some samples and that is helping alot, hope he keeps doing it if he feels like it. Once I know this I'll do it myself of course, my intentions is not to rip people off by no means, I'm talking with desperation view! If it was video I have more tools and a little bit more of knowlegde but with sound problem and as big as this, I dont know what to do since all the tools available in Cool Edit seems very complicated and intimidating.

If I know it can be fixed, and hear it myself we can say we would sell the proyect, but if theres no way tomorrow we'll have to say we cant sell anything leaving 10 hours of wasted material.

We are going to say (at least from this poing) that we wont sell anything because sound is not good.

If in the following hours I get more help and maybe a sample that is possible we could change our response and spend the hours needed to fix it ourselves and learn what it has to be learn, but like I say all the time we need to know is possible and at least some guide on how to do it in Cool Edit or on some other software.

Thanks

Giroud Francois December 28th, 2007 06:41 AM

ok i do my quick very best by applying filters to the file.
I do not try to fix local problem since you got 10 hours of recording and only global filter applied to all the files can be used in a realistic way.
the original
http://www.giroud.com/divers/Corrupted_Sound_long.wav
the corrected version
http://www.giroud.com/divers/Corrected_Sound_long.wav

basically i first remove some noise around 1000Hz, then removed cliks and pops, then setting a filter (around 8Khz) to remove the wireless fadings, then increased volume, then removed again clicks and pops.
it is far from perfect but not too disturbing.

Dot not play from the link because it cause sound to break with pops and click that are not in the file.
save it to your disk and play from there.

Jimmy Tuffrey December 28th, 2007 10:45 AM

My thoughts...

It's the compander circuit in the radio mic.

You probably were not getting enough level and that has made the companding problem worse than normal. Sony have a reputation for this as does Trantec.

Compander circuit is a compressor on the TX and a expander on the RX to give double the dynamic range due to FM 's limited dynamic range.

Sometimes this sounds alot more useable when broadcast due to the average TV set having poor speakers. Your clip has it bad so do your best with eq/noise reduction and then listen on a tv set. Burn it to DVD and judge the results there. God luck and try recording with a higher level at the TX next time.

Jose Milan December 31st, 2007 04:39 AM

Hello Jimmy,

Thanks for the reply, but can you explain a little bit more, I don't know what you mean by TX???

I can increase the level in the camera (XL1s), but that increase the background noise a lot. What I always do is do a test, first silence, then I decrease the levels until I dont hear any more background (sssshhh sound) noise, make the person talk and see if the volume is okay, if not increase the level a little. I trully thought that increasing the levels would worse the problem even more (so I though lowering a little bit more was better).

So any insight if this microphones are any good, or how to be able to use them?? We are going to be making more important projects and can't be having these types of problems any more.

We are cleaning the sound clips and getting okay results, if you people are interested I'll post some samples in the future. It's going to be a lot of work to clean them all.

I would like to thanks Francois for his knowledge and the time he took to provide some samples and his thoughts on all these problem and the motivation he gave me to continue and of course the rest of you people for the tips and insights, if you dont mind keep them coming.

Thanks and a happy new year!

Wayne Brissette December 31st, 2007 05:41 AM

Quote:

Originally Posted by Jose Milan (Post 800343)
Thanks for the reply, but can you explain a little bit more, I don't know what you mean by TX???

TX = Transmitter
RX = Receiver

Upon listening to the samples, I think Giroud's version sounds much better and may be very suitable for your needs.

I do have one question though. One channel, and this is probably where Dave hears the 'echo', is an open mic, my guess is this is the boom mic, yes? If that's the case, you may want to spend some more time cutting this thing apart. When you've got the lav mic going, kill the boom mic. Place the audio from the lav into both channels. When the panel is talking on the boom, kill the lav mic and put the boom on both channels. This may take you a while to do in post, but based on how it's recorded now, it may be the only way to get it up to the level you're expecting to hear.

Wayne

Jose Milan December 31st, 2007 07:02 AM

Hello Wayne,

You're right the open mic is the boom mic.

As for you're tips thats what we're trying to do, mainly from the lav mic but we should use the boom channel also to restore even more.

Thanks again.

Paul R Johnson December 31st, 2007 09:19 AM

There are two problems here. You have a poor recording (ignor the reason) and you need to fix it, but you are also lacking the technical audio skills to do it. Why not find someone near you who can make it the best it can be.

Broadband noise like this - and it's signal strength that is the problem, can be filtered, expanded, compressed or combinations of these - but what isn't recorded is lost - you may be able to mask the noise, but the words spoken at the time of the noise might simply never be recovered. So what you will have to do is treat all the problem areas, then find the same words on the boom track, even if they are distant, sync them up and attempt to replace the lost words with the other track. You'll need to alter the eq to match, maybe filtering out noise above or below the speech frequencies and then see if this can 'lift' you out of trouble during the worst bits.

All this is disaster recovery.

It's too late to tell you all the things you should have done at the recording stage, but having somebody on sound who knows good from bad is pretty essential. A poor sound op is worse than no sound op at all. What they should have been doing is hearing this noise and stopping you recording until fixed. The best sound ops spend a lot of time listening for things they don't want to hear, rather than things they do!


If you have a proper audio editor - not the one in the video editor, you will be able to make it better - how much, depends on the person doing the editing as well as source material.

Sorry
P

Jose Milan December 31st, 2007 10:18 AM

Hello Paul,

We are already making progress and we are making the sound useable.

We try to do test before recording and everything. System (mics) work previously and no problems at all, except for this project (very, very strange). All the pre-test for these recordings worked but in recorded time the sound appear (very, very strange. Later test were recorded--video+sound--and everything was fine).

We could not stop the recordings or the event, so that was not an option.

Like I said I'm not expert in sound, but I'm learning a lot in the proccess, so not everything is bad (trying to be optimistic and see the bright side...:-).

Thanks for the thoughts.

Steve House December 31st, 2007 12:23 PM

Quote:

Originally Posted by Jose Milan (Post 800441)
...

We try to do test before recording and everything. System (mics) work previously and no problems at all, except for this project (very, very strange). All the pre-test for these recordings worked but in recorded time the sound appear (very, very strange. Later test were recorded--video+sound--and everything was fine).

We could not stop the recordings or the event, so that was not an option.
....

Glad to hear that you're making progress.

Couple of points. It's not enough to do tests before recording. You must monitor critically DURING recording as well. A burst of RF noise from someone's Blackberry, for example, may not happen during the test but jump up during the shoot and bite you on the backside - when something like that might happen is a roll of the dice.

You may well have not been able to stop during the event but are you sure? I've been at a number of concert tapings for network broadcast production where they did, in fact, stop tape and restart segments a number of times when somone flubbed a cue, or dropped a line or a technical glitch occured or any number of other things happened. If your event was held specifically in order to tape the presentation, it's not any different from any other TV production. The fact an audience is there during the shoot is irrelevant.

Jimmy Tuffrey December 31st, 2007 09:47 PM

Hi
when i was talking about levels I meant that the belt pack transmitter needed it's gain pot setting just as critically as your cameras level pot/knob.

Each stage of the chain has to be set and optimized. If the gain is too high on the belt pack it will distort before being transmitted and if too low it will mean you hear back ground noise and with certain systems, companding, which sounds like breathy noises that come on with the speech.

What wireless were you using??

Giroud Francois January 1st, 2008 01:35 AM

the sony uwp-c1 never let me down.
use uhf frequency, lower vhf is always fading in some way.


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