Topic: Best way to balance channel levels

[heehaw]

Can anyone suggest what is the serious and well-tried way for balancing levels in audio clip?
For example, I have a 6 channels multitrack live recording (3 x stereo ch) and some of the channels have a various levels from time to time.
And I want to balance those levels, with a not very high impact on the channel dynamics.
For now I'm doing this through channel volume automation and don't use any compressors or limiters.
But of course it's a very time-consuming to do this.
Is there a way to do this more time-friendly?
Is there a software that can do volume automation in a real time manner? So when you raise up some keyframes on some channel it will do this also with the visual impact on this channel?

[page]

Are you mixing down those 6 channels into fewer channels (say, 2) or are you trying to strike an equal balance overall between channels?

If it's the later, read up on RMS values, and then for any given set of tracks you have, calculate the RMS values of sections of content and then add/subtract gain as necessary. Thats one way of handling the second situation.

[heehaw]

Often I'm mixing down to 2 channels some sort of location recordings of folk music that may have in the beginning from 2,3 to 7,9 channels.
Usually it's a camera mic plus a stereo channels from various pocket recorders.
It's a non-amplified authentic folk music mostly from a third world countries, so it's a very special sounding material.
Finding an overall balance between the channels for me it's OK.
What I want is find a good way to smooth out the levels of the audio clips inside some of the channels. The levels between loud and soft parts.
For example, some composition when somebody starts hand clapping at some moment don't let me to raise an overall level of this audio clip for some db.
It's because of short audio peaks that hand clapping may give to audio.
What I'm often do is simply put this region a few decibels down via level automation (Adobe Audition), and rise up when hand clapping is over (for example)



But I'm just think that maybe I can have another way to work with audio like this?
Is there a way to reduce this peaks gently with plugins like hard limiting?
Maybe someone can recommend a book about mixing/mastering basics where I can find an answer for the question like this and more?

[Brian Skalinder]

There are a couple thread pointers in this section's README1st on compression and limiting.  Based on what you've said so far, I think compression or hard limiting would do the trick.

Would love to hear some samples of your recordings, if you're able to share.

[Chuck]

I agree on the advice to use compression and or limiting.

[Church-Audio]

Often I'm mixing down to 2 channels some sort of location recordings of folk music that may have in the beginning from 2,3 to 7,9 channels.
Usually it's a camera mic plus a stereo channels from various pocket recorders.
It's a non-amplified authentic folk music mostly from a third world countries, so it's a very special sounding material.
Finding an overall balance between the channels for me it's OK.
What I want is find a good way to smooth out the levels of the audio clips inside some of the channels. The levels between loud and soft parts.
For example, some composition when somebody starts hand clapping at some moment don't let me to raise an overall level of this audio clip for some db.
It's because of short audio peaks that hand clapping may give to audio.
What I'm often do is simply put this region a few decibels down via level automation (Adobe Audition), and rise up when hand clapping is over (for example)



But I'm just think that maybe I can have another way to work with audio like this?
Is there a way to reduce this peaks gently with plugins like hard limiting?
Maybe someone can recommend a book about mixing/mastering basics where I can find an answer for the question like this and more?

The problem with most guys that are starting out is the are trying to MIX in the box.. There is a reason why consoles have faders. I would suggest getting your hands on a controller or mixer and actually mixing the content instead of just trying to limit it so you dont have to mix it. Often I hear things that are "auto mixed" and guess what they sound like they have been auto mixed. If you are just starting out then you should learn the basics of mixing with a set of faders. But when I have had to do this kind of work I always used an external processor never found anything that was as good as a TC triple C limiter or a Valley People limiter or an aphex stereo limiter. Remember you learn nothing if you just dial in a plugin and let it go. But you do learn how to mix when you have faders in front of you. The best place to start of you are looking for books Mixing Audio: Concepts, Practices and Tools, and the Handbook for sound engineers: the new audio cyclopedia. Both of these books are very good. More information than anyone can absorb in a lifetime of reading. I have been mixing things for well over 20 years now. And I am still learning. Have fun with your project. There are always easy ways to do things.. limiters and compressors, but in the end if you don't learn from them why bother.

Just my two cents.

[cashandkerouac]

It's because of short audio peaks that hand clapping may give to audio.
What I'm often do is simply put this region a few decibels down via level automation (Adobe Audition), and rise up when hand clapping is over (for example)

loud clapping is probably my biggest pet peave and the source of most of my post-production work.  from the pic you posted it looks like you're using Adobe Audition... yes?  that's what i use (version CS 5.5) and i really like it a lot.

1. envelope filter: seems to be the easiest and quickest fix for loud clapping between songs.  it takes a little bit of practive to make a natural sounding transition from the song to the clapping, but the learning curve for this tool is not steep at all. 

2. declicker: this isn't the best tool for eliminating clapping, but it can help slightly.  it is best used for clapping in between songs; not as good for eliminating clapping over the music.

3. auto heal: this is the absolute best tool that i have found for eliminating clapping anywhere on a recording.  however, it is extremely time intensive.  to effectively reduce or eliminate clapping you have to zoom in to highlight each clap and deal with them one by one.  this tool is best used for clapping during the music because you are surgically removing individual claps that only last a fraction of a second.

i also found a link to an article titled "5 Tools for Cleaning Up Audio in Adobe Audition" that may provide some additional assistance.   
 

[nulldogmas]

How would you compare the results of those tools to plain old dynamic compression on sections of loud clapping? It's always served me well, but if there's something I've been missing...

[cashandkerouac]

How would you compare the results of those tools to plain old dynamic compression on sections of loud clapping? It's always served me well, but if there's something I've been missing...

in my opinion compression is much more than a tool for bringing very wide and sweeping dynamics of a recording into a more balanced range.  it's an effect that alters the entire structure and sound of the recording.  i never use compression unless that is the effect i want to hear through the entire recording (which is almost never).

i suppose you could use it (if you really wanted to) for clapping sections in between songs, but smoothing out the transitions from uncompressed music to compressed clapping in between and then back to uncompressed music migh be tricky.  you're probably better off using an envelope filter for that purpose.         

[nulldogmas]

in my opinion compression is much more than a tool for bringing very wide and sweeping dynamics of a recording into a more balanced range.  it's an effect that alters the entire structure and sound of the recording.  i never use compression unless that is the effect i want to hear through the entire recording (which is almost never).

When I use compression for this (which is almost the only thing I ever use compression for, because I agree otherwise ick), I set the threshold very high - higher than all of the music if possible - and only compress above that. So if I have music peaking around -6dB and clapping that is close to 0dB, I can compress the hell out of everything above -6dB and not worry about harming the music.

[page]

in my opinion compression is much more than a tool for bringing very wide and sweeping dynamics of a recording into a more balanced range.  it's an effect that alters the entire structure and sound of the recording.  i never use compression unless that is the effect i want to hear through the entire recording (which is almost never).

When I use compression for this (which is almost the only thing I ever use compression for, because I agree otherwise ick), I set the threshold very high - higher than all of the music if possible - and only compress above that. So if I have music peaking around -6dB and clapping that is close to 0dB, I can compress the hell out of everything above -6dB and not worry about harming the music.

Why not use a limiter then? Any particular reason

[nulldogmas]

Why not use a limiter then? Any particular reason

Because the software I use (SoundStudio) doesn't offer a separate limiter. As I understand it, though, a limiter is just a shortcut for dynamic compression used this way.

[cashandkerouac]

in my opinion compression is much more than a tool for bringing very wide and sweeping dynamics of a recording into a more balanced range.  it's an effect that alters the entire structure and sound of the recording.  i never use compression unless that is the effect i want to hear through the entire recording (which is almost never).

When I use compression for this (which is almost the only thing I ever use compression for, because I agree otherwise ick), I set the threshold very high - higher than all of the music if possible - and only compress above that. So if I have music peaking around -6dB and clapping that is close to 0dB, I can compress the hell out of everything above -6dB and not worry about harming the music.

Why not use a limiter then? Any particular reason

i'm with page... the limiter seems like it makes more sense.  it sounds like you are setting the perameters of the compression to act more like a limiter, which is fine if that works for you.   

[page]

Why not use a limiter then? Any particular reason

Because the software I use (SoundStudio) doesn't offer a separate limiter. As I understand it, though, a limiter is just a shortcut for dynamic compression used this way.

Sure, if you're using an 0ms attack and a microsecond release, otherwise you're impacting the post-tail section of audio in your compression release. Second, many limiters (which, in an oversimplified way, is essentially a very specialized compressor) have more options in how it can be tuned in terms of how it affects the audio, where as with a compressor acting as a limiter you have likely exhausted all of you're tuning options getting it to behave as a limiter.

It's a "right tool for the right job" question in my mind. If my software DAW of choice didn't offer a function, I'd find a (freeware or paid) plugin to do it.

[Gutbucket]

For more natural sounding dymamics control via compression, try the exact opposite approach to limiting- broad, gentle compression.  Set a super low threshold and a very low ratio (like 1.1:1 certainly no more than 2:1), with enough make-up gain so that the transition from non-compressed to compressed sections isn't obvious. 

[nassau73]

It's because of short audio peaks that hand clapping may give to audio.
What I'm often do is simply put this region a few decibels down via level automation (Adobe Audition), and rise up when hand clapping is over (for example)

loud clapping is probably my biggest pet peave and the source of most of my post-production work.  from the pic you posted it looks like you're using Adobe Audition... yes?  that's what i use (version CS 5.5) and i really like it a lot.

1. envelope filter: seems to be the easiest and quickest fix for loud clapping between songs.  it takes a little bit of practive to make a natural sounding transition from the song to the clapping, but the learning curve for this tool is not steep at all. 

2. declicker: this isn't the best tool for eliminating clapping, but it can help slightly.  it is best used for clapping in between songs; not as good for eliminating clapping over the music.

3. auto heal: this is the absolute best tool that i have found for eliminating clapping anywhere on a recording.  however, it is extremely time intensive.  to effectively reduce or eliminate clapping you have to zoom in to highlight each clap and deal with them one by one.  this tool is best used for clapping during the music because you are surgically removing individual claps that only last a fraction of a second.

i also found a link to an article titled "5 Tools for Cleaning Up Audio in Adobe Audition" that may provide some additional assistance.   
 

Great response. I'm a new user as far as post production techniques and found the following video very helpful in the way to use the envelope filter, etc. It also demonstrates the use of the spectral display. I'm using Audition 3.0 so some of the menu items in the video are a bit different than the version the demo is using.

http://www.youtube.com/watch?v=hfp5ze0XTUo

I've only had the chance to edit one show so far where I have used the envelope filter. There were a number of places where I would use the filter on individual claps or hoots from the person sitting next to me. When working on individual loud claps, the drop in the music in the background was almost completely unnoticeable.

In a few instances where this person next to me clapped for an extended period of time, I applied the filter to the entire segment (since there was no music nor stage banter going on). When listening in headphones, there was a noticeable drop in the "ambiance" but the claps were diminished enough so that they didn't just pop out at you enough to make you jump out of your chair!

In some other instances, the auto heal did an amazing job. So far in my limited experience, I've found that auto heal can be applied to only very small segments of audio. Basically, you're eliminating the clap and taking a bit of the audio from one side of the clap and a bit of audio from the other side of the clap and blending them together to "heal" the gap you just created. In most cases, the result is not noticeable.

The other thing that really helped me was once I figured out the level of filtering that worked best with each individual tool, I'd create a shortcut (kinda like a macro in a spreadsheet or word processor). Then it becomes a simple matter of highlighting the audio segment (offending clap) and use your keyboard combination or click the shortcut that you created in the list. Creating the shortcuts in Audition 3.0 is quite different than the demo, but if you poke around a bit, it's easy to figure out.

[Gutbucket]

I've only had the chance to edit one show so far where I have used the envelope filter. There were a number of places where I would use the filter on individual claps or hoots from the person sitting next to me. When working on individual loud claps, the drop in the music in the background was almost completely unnoticeable.

That is extremely effective, with minimal effect on the music.  It just takes a lot of work since you do all the work as the compressor/limiter.  It's much more challenging to set compressers and/or limiters to do that automatically without unacceptible audible compromises.

In some other instances, the auto heal did an amazing job. So far in my limited experience, I've found that auto heal can be applied to only very small segments of audio. Basically, you're eliminating the clap and taking a bit of the audio from one side of the clap and a bit of audio from the other side of the clap and blending them together to "heal" the gap you just created. In most cases, the result is not noticeable.

This is similar to manually drawing volume envelopes in its "surgical" correction of breif anomolies.  It also takes a lot of work to address each instance.  But it goes farther in that it can be very effective at greatly reducing unwanted short durration noises that are not necessarily simply "over-loud" such as coughs, squeeks, clinks, pops, and other audience noises. "Auto heal" sounds like Adobe Audition's specific term for the function.  FYI, you will find similar functionality in other softwares refered to as "Spectral Repair" or a term similar to that.