Need advice; using Audition to remove hiss (and noise?)...

[takearushfan]

Hi again,
First off, I'll mention that even though I'm proficient with Audition 3.0, or so I thought, I do have some other apps for A/V work. However, I've never really experimented with them. I have Sound Forge Pro 10.0, Vegas Pro 9.0 and a Noise Reduction Plug-In 2.0. Would any of those be more efficient at removing hiss than Audition? Obviously, I'm tempted to try the noise reduction plug-in, but I don't believe it's noise I'm trying to remove. This leads me to a question I've been wondering for a while: What's the different between hiss and noise? How do you tell the difference? How do you know what it is that you're trying to remove? If you're not turned off already, should I provide a (lossless) sample?
Anyway, on to my main question(s)...
I thought I did a fair job of removing hiss in various parts of an audio clip. Then, I cranked up my volume and was horrified at how obvious the hiss was. It's not pleasant to work your butt off, only to find out that at a loud volume, the flaws stick out like a sore thumb.
What are the most efficient ways of removing hiss (and noise?)? ... and, how do you properly balance how aggressive or "laid-back" you should be when tinkering with the settings? For example, I've noticed that if I'm too lax, then naturally there's more hiss than desired. However, if I'm too overzealous, it creates a sort of "underwater sound"; not sure how to describe it, but I hope someone knows what I mean.
Sorry for the long-winded post, but I feel it's probably a better idea to provide as much information as possible, at the risk of annoying some, than to provide too little information and have you all wondering of the specific details.
Thanks in advance,
Justin

[zoobie]

Yes...the underwater gurgling sound...I know it well...too much effect
Is this a song you're working on? if so, perhaps you can get a better version of it
you must realize that there's only so much you're going to be able to do with audio
these don't work miracles
I use the free Audacity which also has noise reducing filters
but again...there's only so much you can do

[takearushfan]

Hi,
Thanks for replying.
It's not a song, it's from a film, and not a VHS transfer or anything like that. It's from a DVD.
Can you explain what causes that annoying underwater sound? I mean, how do I know how much or how little effect to apply... trial and error?
I posted in another thread, that nobody replied to, how I'm amazed by the number of DVDs that have an incredible amount of hiss. Some DVDs have obviously been cleaned, using what I don't know, but the results are mind-blowing. However, the majority have either an "acceptable" amount of hiss, then some that are unbelievably poor. I mean you truly cannot believe that they released something with such an outrageous amount of hiss! What's scarier is that I'm not referring to these film's original Mono mixes, but rather the remastered 5.1 mixes. I just don't get it.
I'm posting a lossless sample (around 30 seconds) of the track I'm working on. This clip is obviously before I've done any work. Note that I need the ticking clock to be quite audible.
Thanks,
Justin

[zoobie]

you could simply put a ticking clock on another track in your audio editor

[zoobie]

I listened to your wav...it sounds like it was put to DVD from cassette tape...pretty bad
I ran it thru Audicity and it cleaned it up somewhat...give it a try...Audacity>Effects>Noise Removal

[takearushfan]

I listened to your wav...it sounds like it was put to DVD from cassette tape...pretty bad
I ran it thru Audicity and it cleaned it up somewhat...give it a try...Audacity>Effects>Noise Removal

Oh, no... see, I boosted/adjusted the sections that I felt needed/deserved it and that's why the extreme hiss now exists. It wasn't that bad originally. It's that bad now, after I made what I feel are the deserved boosts in volume. However, even though the hiss is horrendous, I believe it's appropriate for the volume to be as loud as I made it.

[netmask56]

How did you transfer the DVD to your computer?

Listening to the track you provided I can hear audio compression that is raising the level during periods of audio inactivity. It sounds like there is an automatic record function going on somewhere in the chain.

re the amount of any effect or filtering to use, there is one answer "use your ears to listen critically on a very good set of speakers with a flat frequency response and make an aural judgment" If filtering makes a gurgling sound then it's way way over done.

The other area to investigate is your monitoring amplifier - what type is it ? what power? Sometimes I have seen set ups where there is a DVD player that has it's own volume control on the output (bad practice) that is turned way down and the input amp volume control is consequently turned right up. The result hiss on everything.

The other area is poor loudspeakers that have a peaky response that accentuates the high mid range - result hiss. But this is not on the original only in the playback chain.

In other words there are many many variables in your problem and you need to post as many details of the whole system to be of any help...


EDIT: Just read your reply above - basically you can't expect to raise the level in quiet passages of a commercial disc without incurring deficits - you don't know the nature of the original - was it location sound? if so it will have some low level hiss and even wind if out doors. The level it has been mixed has be decided by the producer and dubbing mixer. If the original sound was recorded by you then a better microphone technique could have been employed - boosting low level sounds will always have problems unless they were digitally created in the first place like in electronic or midi music etc..

[takearushfan]

I just used DVDFab to transfer to my hard drive.
I'm using two things to monitor the amount of hiss; my 5.1 setup, with the Windows volume up to 100%, and (also with the Windows volume up to 100%) a nice set of cup headphones.
I haven't yet tried that audio on my DVD software, as I need to fix the audio first, hence my posting here. I also need to set the proper variables in my Surround encoder.
Regarding how it was mixed, dubbed, etc... I'm relying on two things to verify that the parts I'm boosting should be enhanced: My own recollection of the film, from VHS; and people I've asked that saw the original either on VHS or even in the theater, when originally released. The verdict is that these quiet parts are way too low, compared to how they were initially. I don't know why, but I can only guess it's from years of deterioration. The audio on this DVD sounds like it's taken from a 10K-generation transfer
Thanks,
Justin

[takearushfan]

Here's a sample of the same clip as above, but with hiss reduction applied. Like you've said, there's only so much I can do. That is, without reducing the audio elements that I'd like to have apparent. Any suggestions?

[netmask56]

I didn't realise it was from a VHS original. The signal to noise ratio of VHS is not very good unless it came from the "HiFi" track assuming it had one and then you can be plagued with tracking errors and drop outs. Otherwise the linear audio tracks were really dreadful with their frequency response falling off above 8Khz and in some machines I've tested not much above 5KHz. PAL machines were generally better than NTSC but not much. I would isolate the low level areas and pass them through a lo pass filter set to around 3Khz or even lower - trial and error approach and then use a harmonic exciter plugin to add back harmonics and a bit of sparkle. Boosting the highs using conventional graphic or other types of boost will only bring up noise and hiss. That's where harmonic excitation comes in it adds subjective highs without raising the level or causing distortion. I have restored many early talkie 1930"s movie sound tracks as well as Edison cylinders and HE's are one of the most useful tools I've used. There are plugins available for Audition. http://www.izotope.com/support/help/ozone/pages/mod_harmonic_exciter.htm as an example.

[takearushfan]

I didn't realise it was from a VHS original. The signal to noise ratio of VHS is not very good unless it came from the "HiFi" track assuming it had one and then you can be plagued with tracking errors and drop outs. Otherwise the linear audio tracks were really dreadful with their frequency response falling off above 8Khz and in some machines I've tested not much above 5KHz. PAL machines were generally better than NTSC but not much. I would isolate the low level areas and pass them through a lo pass filter set to around 3Khz or even lower - trial and error approach and then use a harmonic exciter plugin to add back harmonics and a bit of sparkle. Boosting the highs using conventional graphic or other types of boost will only bring up noise and hiss. That's where harmonic excitation comes in it adds subjective highs without raising the level or causing distortion. I have restored many early talkie 1930"s movie sound tracks as well as Edison cylinders and HE's are one of the most useful tools I've used. There are plugins available for Audition. http://www.izotope.com/support/help/ozone/pages/mod_harmonic_exciter.htm as an example.

I must've worded my last post poorly, unless I'm just not understanding you (very possible) It's not from a VHS; it's from my DVD. I used Smartripper to extract the audio track.

[netmask56]

I just used DVDFab to transfer to my hard drive.
I'm using two things to monitor t My own recollection of the film, from VHS; and people I've asked that saw the original either on VHS or even in the theater, when originally released. The verdict is that these quiet parts are way too low, compared to how they were initially. I don't know why, but I can only guess it's from years of deterioration. The audio on this DVD sounds like it's taken from a 10K-generation transfer
Thanks,
Justin

I took it was a DVD made from a VHS as per your quote - anyway the same issue arises if you try to boost low level material that was deliberately mixed low level you are going to have hiss and possibly system noise from the original recording. You go on to say

The audio on this DVD sounds like it's taken from a 10K-generation transfer

So what you are trying to do is near impossible without a lot of work and effort and the availability of the right tools . If your source material sounds like 10th generation then there really isn't much you can do with it without spoiling the whole overall sound design.

[takearushfan]

Oh. I see how there could've been a misunderstanding. What I meant was that if you compare the DVD's audio track with the one from a VHS or the one originally released in the theater, the DVD's track is "screwed" (for lack of a better term).
I'm up to the work and effort, but yes, I'm definitely lacking the right tools. The only thing I can think of that would be significantly better was if I had ProTools; actually, even then it might not have the restoration "power" that I'm looking for. I don't know all of what ProTools can do. Though, I can't imagine that it doesn't have some sort of restoration features.

[netmask56]

For what you want to do Pro Tools is overkill compared to Audition - I'm not sure what your experience in the audio world is but it is not an area that one sale into without some training and experience. It's a bit like the kids I sometime interview who wake up one morning and say "I want to be a Hollywood Cinematography - like next week!" and yes I have had that actual experience. It is easy enough if you are computer literate to teach yourself most audio and video editing programs but value judgements only comes with experience and time. The fat that you want to raise or alter the balance of a commercial soundtrack on a DVD where professional have made artistic judgement is a bit questionable in my mind. So I wish you luck!

[takearushfan]

Well, I was just tossing ProTools out there. I didn't actually consider it a possibility. That'd be far too much. It's not as if I'm a professional sound engineer for Sony or such, heh. Honestly, I haven't even been to school for this hobby that I obsess over. However, I've been experimenting for years and you're right... I've found that it's really my best judgement that yields the best results. I could've gone on without starting this thread, but I figure knowledge is power (as cliche as that is), so I thought I'd get some other opinions.
As a final note, I'd like to state that what I'm experimenting with is taking a Mono source and creating 5.1 out of it. Not anywhere near easy, but I'm finding that with excruciating work, it's far more possible than I originally thought...
I am doing this solely as an educational learning experience; nothing being sold, no illegal activity, etc. < probably unnecessary, but sometimes people wonder.

[lordsmurf]

Pro Tools is for other tasks -- not restoring audio.

[takearushfan]

My nephew owned a recording studio, just for musicians, not film. I had the benefit of seeing what Pro Tools can do and you're right. I even asked him and he said there's nothing on there meant for heavy-duty restoration. In fact, he named some plug-ins that I'm used to dealing with in Audition, so... nothing special, as far as he could tell.

[netmask56]

Oh. I see how there could've been a misunderstanding. What I meant was that if you compare the DVD's audio track with the one from a VHS or the one originally released in the theater, the DVD's track is "screwed" (for lack of a better term).
I'm up to the work and effort, but yes, I'm definitely lacking the right tools. The only thing I can think of that would be significantly better was if I had ProTools; actually, even then it might not have the restoration "power" that I'm looking for. I don't know all of what ProTools can do. Though, I can't imagine that it doesn't have some sort of restoration features.

http://www.berkleemusic.com/welcome/free-protools-lesson?pid=2302&keyword=free-pt-less...FQtKgwodF1cv_A

[2Bdecided]

Noise Reduction Plug-In 2.0

Use that. Learn how to use it properly. Mode 2 usually works best for me. YMMV.

Cheers,
David.

[lordsmurf]

A lot of those plugins are just so-so quality, too. You're best off with dedicated apps.

[takearushfan]

A lot of those plugins are just so-so quality, too. You're best off with dedicated apps.

You mean there are apps specifically meant for the kind of restoration I'm looking for? I never thought of looking for that. What are some ideal apps to use?

[pandy]

Hi,
Can you explain what causes that annoying underwater sound? I mean, how do I know how much or how little effect to apply... trial and error?

My 2 cents

This effect is directly from idea behind noise reduction - profile that you take (spectrum of noise) can have tones (it is not pure noise but combined noise and frequencies), can be non-constant (noise spectrum is dynamic during time line) also what is really important - spectrum subtraction is not universal cure for all noise issues - "spectral leakage" - lowering some noises in one place also new artifacts can be introduced.

http://en.wikipedia.org/wiki/Spectral_leakage

So only after some experiments optimal (less artifacts as possible) solution can be find and always ears are best judge in the terms of quality.

[2Bdecided]

A lot of those plugins are just so-so quality, too. You're best off with dedicated apps.

?!

All decent NR algorithms I know of* are available as plug-ins for something. Several aren't available in stand-alone form.

* = except maybe the full CEDAR range - but I think that's probably beyond the OP's budget!

If you have something in mind, please share.

The NR-2 bundle (previously branded Sonic Foundry, now branded Sony) is great - in some respects, it easily matches products costing 10x as much.

Cheers,
David.