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| PM5D Multi-Band Compressor [message #365438] |
Wed, 01 October 2008 19:19  |
Lyle Corbin
Messages: 7
Registered: October 2008
Location: Bothell, WA |
Newbie |
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I'm trying to use the M. Band Comp effect to do some frequency-specific compression and am having trouble figuring out how the thing works. Whenever I set the ratio to something greater than 1:1 (say 4:1), as I lower the threshold on a band it is increasing the volume in that band even when the input signal is way less than the threshold. It's looks like it's acting kind of like an expander, but I can't quite figure it out. If you have used this effect, can you give me some tips?
I want it to behave like a normal compressor that leaves the input signal untouched until the threshold is reached for each band. I'm inserting this effect into the stereo mains. In our case, I want to have it limit/compress the midrange and high end to some extent, but only beyond a certain level, while letting the low end pass unencumbered.
I originally was looking at using the regular output compressor on the stereo mains but there doesn't appear to be a good way to make that be post-fader, an important requirement.
Thanks for your input!
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| Re: PM5D Multi-Band Compressor [message #365445 is a reply to message #365438 ] |
Wed, 01 October 2008 19:28  |
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Andy Peters
Messages: 8151
Registered: April 2004
Location: Tucson, AZ |
Has No Life
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| Lyle Corbin wrote on Wed, 01 October 2008 17:19 |
I originally was looking at using the regular output compressor on the stereo mains but there doesn't appear to be a good way to make that be post-fader, an important requirement.
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If your compressor is post-fader, then pushing up on the fader is the same thing as setting the threshold lower.
-a
Pat Robertson, go fuck yourself.
"On the Internet, nobody can hear you mix a band."
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| Re: PM5D Multi-Band Compressor [message #365448 is a reply to message #365445 ] |
Wed, 01 October 2008 19:38 |
Lyle Corbin
Messages: 7
Registered: October 2008
Location: Bothell, WA |
Newbie |
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Sure, and that's OK. In this case, because it's on the Stereo A buss, for any given frequency a particular signal level corresponds to a certain dB level in the room. I want to compress based on volume levels in the room (output signal of Stereo A buss) not on the operator's gain structure (input signal of Stereo A buss).
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| Re: PM5D Multi-Band Compressor [message #365450 is a reply to message #365448 ] |
Wed, 01 October 2008 19:46 |
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Andy Peters
Messages: 8151
Registered: April 2004
Location: Tucson, AZ |
Has No Life
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| Lyle Corbin wrote on Wed, 01 October 2008 17:38 |
Sure, and that's OK. In this case, because it's on the Stereo A buss, for any given frequency a particular signal level corresponds to a certain dB level in the room. I want to compress based on volume levels in the room (output signal of Stereo A buss) not on the operator's gain structure (input signal of Stereo A buss).
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I realize this discussion is veering off of your topic, but ...
When you do this, I assume that you're setting the compressor up as an AGC. In other words, shortish attack time but very loooooooong release time.
Done this way, the compressor doesn't try to follow the program material dynamics, but rather it sorta acts as an invisible hand on the master fader, pulling it down decisively when you go above threshold, and slowly pushing it back up when you go back below threshold.
Anything other than that and you get mush for output.
-a
Pat Robertson, go fuck yourself.
"On the Internet, nobody can hear you mix a band."
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| Re: PM5D Multi-Band Compressor [message #365451 is a reply to message #365450 ] |
Wed, 01 October 2008 19:49 |
Lyle Corbin
Messages: 7
Registered: October 2008
Location: Bothell, WA |
Newbie |
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Yes, that is the desired effect. Good suggestion, and I will be sure to set things up that way - if I can get the M. Band Compressor to not mess with things below the threshold!
Thanks!
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| Re: PM5D Multi-Band Compressor [message #365486 is a reply to message #365482 ] |
Wed, 01 October 2008 21:21 |
Lyle Corbin
Messages: 7
Registered: October 2008
Location: Bothell, WA |
Newbie |
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I tried a number of values - mostly leaving them at zero since that was the default setting and other settings I tried didn't seem to give me what I wanted. However, I'll try -18 dB and see what happens. Thanks!!
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| Re: PM5D Multi-Band Compressor [message #369726 is a reply to message #365486 ] |
Thu, 16 October 2008 19:55 |
Lyle Corbin
Messages: 7
Registered: October 2008
Location: Bothell, WA |
Newbie |
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For the benefit of others, I contacted Yamaha and here's what I got:
| Quote: |
Here is how Multi-band Dynamics/Comp works:
It amplifies the gain so that the input signal @0dB is calculated based on Threshold and Ratio, automatically being made up to 0dB output.
For instance, a Threshold=-6dB, Ratio=2:1 signal will simply be gained by 3dB.
When I am talking about "auto makeup", output gain (how much it is compensated) is always calculated based on the Threshold/Ratio relationship, no matter if the input signal is reduced or not, which means it works most efficiently when the input signal is @ 0dB.
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I've requested the ability to turn off the automatic make-up gain functionality, but at least they say that the make-up gain is strictly a function of the threshold and ratio settings and is not dependent on the input level. I've confirmed this (as much as possible doing a very brief test) by playing with it.
So, to have no effect on the signal when it's below the threshold, you need to set the gain to: gain=threshold-(threshold/ratio). For example, if the threshold is -20dB and the ratio is 3.5:1, the gain should be (-20-(-20/3.5)) = -14.3 dB. Then it seems to work.
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| Re: PM5D Multi-Band Compressor [message #370699 is a reply to message #369726 ] |
Mon, 20 October 2008 23:51 |
 Rick Stansby
Messages: 1959
Registered: November 2004
Location: Davis, California |
Has No Life |
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| Lyle Corbin wrote on Thu, 16 October 2008 17:55 |
For the benefit of others, I contacted Yamaha and here's what I got:
| Quote: |
Here is how Multi-band Dynamics/Comp works:
It amplifies the gain so that the input signal @0dB is calculated based on Threshold and Ratio, automatically being made up to 0dB output.
For instance, a Threshold=-6dB, Ratio=2:1 signal will simply be gained by 3dB.
When I am talking about "auto makeup", output gain (how much it is compensated) is always calculated based on the Threshold/Ratio relationship, no matter if the input signal is reduced or not, which means it works most efficiently when the input signal is @ 0dB.
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I've requested the ability to turn off the automatic make-up gain functionality, but at least they say that the make-up gain is strictly a function of the threshold and ratio settings and is not dependent on the input level. I've confirmed this (as much as possible doing a very brief test) by playing with it.
So, to have no effect on the signal when it's below the threshold, you need to set the gain to: gain=threshold-(threshold/ratio). For example, if the threshold is -20dB and the ratio is 3.5:1, the gain should be (-20-(-20/3.5)) = -14.3 dB. Then it seems to work.
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Am I the only who is confused? A while back I tried to use the multi-band compressor patched across the L,R outputs. I figured I would start by only compressing the mids. I found that lowering the threshold on the mids boosted the mids. I quickly gave up. I can certainly calculate appropriate gains using your formula, but I don't understand why it would be set up that way.
Rick
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| Re: PM5D Multi-Band Compressor [message #370710 is a reply to message #370699 ] |
Tue, 21 October 2008 00:44 |
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Andy Peters
Messages: 8151
Registered: April 2004
Location: Tucson, AZ |
Has No Life
Contrarian |
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| Rick Stansby wrote on Mon, 20 October 2008 21:51 |
Am I the only who is confused? A while back I tried to use the multi-band compressor patched across the L,R outputs. I figured I would start by only compressing the mids. I found that lowering the threshold on the mids boosted the mids. I quickly gave up. I can certainly calculate appropriate gains using your formula, but I don't understand why it would be set up that way.
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Are you sure that the "auto gain" wasn't turned on?
Whoops, the multi-band comp doesn't have that feature, unless it's hidden. The Comp276 has an "Auto Makeup" function. I be confused. Sorry.
-a
[Updated on: Tue, 21 October 2008 00:54]
Pat Robertson, go fuck yourself.
"On the Internet, nobody can hear you mix a band."
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| Re: PM5D Multi-Band Compressor [message #370711 is a reply to message #370699 ] |
Tue, 21 October 2008 00:45 |
Lyle Corbin
Messages: 7
Registered: October 2008
Location: Bothell, WA |
Newbie |
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| Quote: |
Am I the only who is confused? A while back I tried to use the multi-band compressor patched across the L,R outputs. I figured I would start by only compressing the mids. I found that lowering the threshold on the mids boosted the mids. I quickly gave up. I can certainly calculate appropriate gains using your formula, but I don't understand why it would be set up that way.
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I agree! I've asked them to change it, but maybe if you contact Yamaha Commercial Audio support and let them know you feel the same way they'll see that I'm not the only one who is confused! While it makes a bit of sense mathematically once you know how it works, it is not something you can really figure out just by playing with it and it certainly isn't documented!!
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| Re: PM5D Multi-Band Compressor [message #370713 is a reply to message #370710 ] |
Tue, 21 October 2008 01:02 |
Lyle Corbin
Messages: 7
Registered: October 2008
Location: Bothell, WA |
Newbie |
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Are you sure that the "auto gain" wasn't turned on?
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Don't see an "auto gain" in the effects parameters. I certainly would have noticed that. Here's the complete list of configurable parameters:
Low gain, Mid gain, Hi Gain, L-M XOver, M-H XOver, Slope, Ceiling, Lookup, Low Thres, Mid Thres, Hi Thres, Ratio, Attack, Cmp. Rel., Knee, and Comp. Bypass.
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| Re: PM5D Multi-Band Compressor [message #370730 is a reply to message #370713 ] |
Tue, 21 October 2008 06:20 |
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Michael 'Bink' Knowles
Messages: 4095
Registered: April 2004
Location: Oakland, CA |
Has No Life |
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| Lyle Corbin wrote on Mon, 20 October 2008 23:02 |
...Here's the complete list of configurable parameters:
Low gain, Mid gain, Hi Gain, L-M XOver, M-H XOver, Slope, Ceiling, Lookup, Low Thres, Mid Thres, Hi Thres, Ratio, Attack, Cmp. Rel., Knee, and Comp. Bypass.
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Are attack and release times the same for all frequency bands? I would have expected that the lows would be slower.
-Bink
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| Re: PM5D Multi-Band Compressor [message #370861 is a reply to message #370730 ] |
Tue, 21 October 2008 14:16 |
David Sumrall
Messages: 171
Registered: May 2004
Location: Orlando Florida |
Has No Life |
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Yep, been one of my complaints on the Yamaha multibands since they added them is that they are set to auto gain with no option to turn them off of that setting.
I love having a some mutiband compressors or dynamic eq's on specific things.
It would be great to have this function without the "auto" part.
Been asking for that for a while.
My 2 cents!
David
David Sumrall
Production Manager/A1
First Baptist Church Orlando
www.firstorlando.com
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