Automatic Gain Control or Compressor

NoizyNeighborz

Hey Guys,
I am in a weekend Rock N Roll / Pop dance band).
I have been using the 260 successfully for some time now and its time to dig a little deeper into what it may be able to do for me.

I am wondering about the use of the Comperssor and or the AGC to bring up quiet parts of a performance. We mix our sound from stage (set and forget) and there are parts of some songs that get too quiet.

Example: We have the acoustic guitar set at a low volume in the mix. When we play the acoustic guitar intro to Heart - Crazy On You it sounds lame because the volume is so low. Of course when the rest of the instruments join in we need this instument in the background again.

Could the compressor or AGC be used to keep the bands volume constant? (and bring the solo acoustic guitar to the foreground). I tried a little experimenting, but always had problems like feedback, pumping, and loss of control from the mixer. I also wonder what effect these 2 signal processors have on the gain structure.

Any thoughts??
Thanks
Wally

Gadget

Wally...
DO NOT USE THE AGC!!!! :shock:

The Compressor might be able to help here but I need a WHOLE lot more info...Give it all to me including the .dwp file you use for your setup.. I also need all the equ you have with your setup....
G

Dennis

Is there not some kind of guitar foot pedal that could be used to boost the acoustic guitar level for the "Crazy On You" intro?

Dennis

Gadget

Of course there is... BUT do you really NEED it?

Why not assign the acoustic to a couple channels (if you have them) ? That way you could have a couple different EQ setups and even pan the guitar to make for a more full sound... there are a bunch of tricks you can use but if the gutiar is susceptible to feedback then we have a problem... open sound holes can cause HAVOC~! but there is help...

What are your resources for dealing with the acoustic problem? can you afford a sound hole dampener? Does the guitar have piezo bridge pickups?

You have 24 peq filters (4 per output) and a 28 band GEQ or 9 band PEQ available on each input.

with this we can overcome most problems...

G

NoizyNeighborz

Is there not some kind of guitar foot pedal that could be used to boost the acoustic guitar level for the "Crazy On You" intro?

Dennis, it's an Ovation guitar with its own gain and EQ, but it cannot be increased because of feed back in the monitor's. Thanks for the suggestion. This was just one example, on one instrument. What I really was thinking of was bringing up everything in the mix whenever the vocals were not present. My theory was since the vocals should be "loudest", when they are not present the AGC or compressor would bring up the mix. The more stuff missing from the mix, the more the gain would be adjusted.

Gadget

Wally...
DO NOT USE THE AGC!!!!

1. Because of your warning my assumptions on AGC use must be totally flawed. I did a search on it here, but didn't find much. I won't use it, but would like an explanation if you have time.
2. I'll play around with compression and see if that helps at all. Any pointers here (I don't want you to do the work for me... yet ).

I know having a FOH dude would be a better way of controlling levels, but we can't afford that. This is not a show stopper issue, I'm just looking for another way to make our "Set and Forget" system work a little better. Also I want to learn more about the DR260!

Thanks Guys
Wally

Dra

If the guitar feeds back in the monitors, then AGC, compression, etc are also going to cause feedback. Another solution is needed.

DRA

NoizyNeighborz

If the guitar feeds back in the monitors, then AGC, compression, etc are also going to cause feedback. Another solution is needed.

Dra, I don't think this is the case because the AGC/Compression of the DR260 is only on our mains. We use a seperate aux send and EQ for the monitors. We don't normally have any feedback issues with our mains... even when I remember to boost instruments for breaks and intros. Also it's not just the acoustic guitar, as stated in a previous post. I'm just trying to get the 260 to do some more of the FOH engineers (that's me on stage playing) work on the overall mix/levels. The acoustic guitar intro was my most extreme example.

Thanks for the reply
Wally

Dra

My bad. But still, you'll have balance problems when other instruments join in (lead guitar in your example).
Is the acoustic running through a processor? Could it? Dennis' idea of the foot pedal is a good one, but montitor volume still has to be addressed in either case.
Gadget's idea of using a twin channel (no monitor on the second) I think is your best bet, but someone still has to manually work the fader.

DRA

Dennis

Wally

You are not completely off base on your thoughts of automatic mixing solutions but I don't think you will have total success in a live music situation. These solutions are used in conference rooms or presentations with multiple lavaliere mics where the "live mic" is boosted and unused mics are reduced. The ambient, average noise level in these situations is NOT 95 - 100 dB.

You will need to deal with your issues one at a time. Going back to the acoustic guitar that we have all fixated on...Gadget's 2 channel solution is the correct call. The acoustic guitar player will need a foot switch that will switch the signal between the two acoustic channels on the mixer in order to maintain the "set it and forget it" nature of the sound system.

Dennis

NoizyNeighborz

Thanks Dennis, I was not thinking the DR260 would be used in other applications other than live music :oops:

The foot switch is a good idea for that application. Can you get an A/B switch that wouldn't pop when you change channels?

So would you not have any examples of using the DR260's AGC or Compression for live music?
Or is it strictly a no-no.

Wally

Dra

Compression - for 1 mic or instr (screaming comedian, for example)
AGC - dinner music from CD or 1 mic where source level could change a lot

DRA

Dennis

The A/B switch would be switching balanced lines AFTER the DI box. All of the pin 1's (ground) would remain permanently connected and pins 2 and 3 (+ and -) would be switched by a double pole, double throw switch. Ground never breaks and there should be no pop.

I would never use AGC or over all compression on a live music mix. DRA summed it up pretty well.

Dennis

Gadget

I can think of a few times I did compress the whole mix.. it was for a band that was all over the place sonically.. and I detailed the procedure in the FAQ section...

The problem with AGC is it "level hunts"... it try's to make everything the same volume and in a lively situation like live sound it would take all the dynamics out of the mix, and there would be a pumping sound associated with it's use... not good...

A Limiter can be used as a leveler of sorts as well... nothing happens to quiet passages but overly dynamic sounds will be held to the level you set as the max output.

One other possibility, run the system mono and use the other channel for the guitar players monitor as a controller... set the HPF for the monitor @ about 60hz use the procedure set forth in the Auto EQ posts in the FAQ section to flatten the monitors and you'll be likely to have much more gain before feedback...

G

NoizyNeighborz

Thanks guys,
We may try the foot switch idea if I can free up a mixer channel. The big thing here is I learned that the DR260 can be used in a variety of applications, and not all of its features can be applied to each application.

Thank you again
Wally