# use of compression during live performance



## temper (Jan 22, 2013)

Hey all, so I'm looking for a some advice on compression. The short back story is that I'm slowly taking over the technical direction at our church and frankly I'm having to take a fine tooth comb to everything. I'm currently working on getting a usable, sensible sound system set up so I can start training volunteers how to really run it. 

We have a band that I keep on thinking could use compression on a bunch of mics and instruments. Also, we are starting to do a lot more creative theater work at church and this has led to lots of lapel and ear-piece wireless mic usage. So, there is just so much dynamic range going on that I know we have to do something. I know that properly trained singers, musicians and actors can keep there dynamics in check but that's asking way too much from a volunteer group. (Not bashing our talent in any way, it's just the way it is).

So, the question is, what would be the best way to address this? The requirements are that whatever I do will have to be simple for sound techs to be trained on and use, it needs to be rather inexpensive, and it will only be used for live sound. These are the possible scenarios I've come up with.

1. Add a compressor to the main inserts. This would be very simple 'set and forget' if the settings were light. I'm thinking it MIGHT be workable and do enough good to just take off the worst spikes. I could buy a rather decent compressor if just buying one.

2. Add a compressor to sub master inserts. I don't know if our board actually has submaster inserts, and regardless, I've found that submaster busses confuse and frustrate volunteer sound techs a lot. So, the idea of assigning all vocals to a submaster and using compression on it is great in theory but I think it's not a great configuration for volunteers to work with. 

3. Add compressors to individual channels that need it, ie lead singer, anyone with a lapel/ear mic, bass, drums. I'd probably need 6 channels in total, so I'd be forced into cheaper compressors. This would also mean that the sound tech would have to insert the compressor on the right channels as needed, something that makes life more complicated for a volunteer sound tech.

4. Just buy 16-20 channels of compressors and leave them on each channel. I'm talking like 4 behringer mdx4600s. I know it sounds crazy, but I'm trying to simplify stuff so that we aren't plugging/unplugging stuff in the sound booth ever. 

More than likely we'll be buying a different mixer in about a year as our current one is dying a slow death, but I'm not at all sold on a digital board. I know many/most have a compressor on each channel, but I'm not really sure if I want to unleash volunteer sound techs on a digital board yet. There's something very simple and elegant about a good 2 bus / 4 aux analog mixer that makes training new people very easy.

So, what would you guys do? How important is compression, how difficult is it to get right, much many channels, etc?


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## NickVon (Jan 22, 2013)

before anyone else hops in. here are some questions they are going to ask

1) What is your current console you are using
2) Do you already have outboard compressors, if so how many, what kinds.
3) at any given time how much "stuffs" are you running. (Band, singer on handheld, 8 people on wirless lapels, 20p Choir)
4) Is there a budget beyond what (4) MDX4600s would cost.


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## temper (Jan 22, 2013)

NickVon said:


> before anyone else hops in. here are some questions they are going to ask
> 
> 1) What is your current console you are using
> 2) Do you already have outboard compressors, if so how many, what kinds.
> ...



The current mixer is a mackie cfx16. It's definitely a little out of its league. . We don't have any outboard compressors at the moment. Here's a full service.

electric drums
bass
acoustic guitar 
electric guitar
keys x2
vox x4 (wired)
wireless lapel/ear 1x-4x
av feed

you can see that the board gets filled up in a hurry. The budget is actually quite flexible. This is more of a long term exercise so depending on what I decide we'll just save up for it.


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## Aman121 (Jan 22, 2013)

As much as you may not like to hear it, it may be time I go digital. Buying 16 channels of compressors of questionable quality and a new analog console doesent make sense to me, at least with the info you've given. While they may seem daunting at first, many digital boards aren't that much harder to run than an analog, and in fact can be much more intuitive after users are somewhat competent. There are many excellent entry level digital options out their, such as the behringer x32. You can also upgrade a bit to one of the roland digitals or a Yamaha LS9. Still, at only 3k for a 32 channel console, the x32 might be a good solution for you.


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## Morte615 (Jan 22, 2013)

Not normally the way I would recommend it but you could get a decent compressor/limiter and run it through the effects bus on the mixer. Set the compressor kinda high and then set the individual channel effects to use the amount of compression you need. Not perfect (not even really good) but may work. I've never tried something like this so not sure if it would work at all.

As has been mentioned I would recommend going with a digital board as soon as possible. In the long run with the amount of processing you are talking about it would be easier all around.


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## Footer (Jan 23, 2013)

Aman121 said:


> As much as you may not like to hear it, it may be time I go digital. Buying 16 channels of compressors of questionable quality and a new analog console doesent make sense to me, at least with the info you've given. While they may seem daunting at first, many digital boards aren't that much harder to run than an analog, and in fact can be much more intuitive after users are somewhat competent. There are many excellent entry level digital options out their, such as the behringer x32. You can also upgrade a bit to one of the roland digitals or a Yamaha LS9. Still, at only 3k for a 32 channel console, the x32 might be a good solution for you.



My feeling as well.... the X32 is made for you. 2900 bucks and your done... and you will have so much more functionality. There is a reason that outside of the DBX 160, you are hard pressed to buy a good analog compressor. Most companies outside of the recording world simply don't make them anymore. Investing more money in your current setup is not really a good investment. Save your cash a bit and go digital. I really can not recommend the X32 enough for this exact setup.


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## FMEng (Jan 23, 2013)

Compressors on subs or busses works but I would much rather have one compressor per vocal channel. It helps in keeping voices blended together much easier, and reduces the workload on the person mixing. One of the problems of one compressor doing many channels is that a louder voice can push down softer voices in the mix and it can make mixing counter intuitive.

The main reason to avoid one compressor per channel is if the vocalist objects to hearing themselves squished in the monitors. Some professional singers absolutely hate that because they push for more volume and they don't get any. I doubt you'd encounter that in a church setting and only a lead would get special consideration.

I generally would not put compressors on the instruments. That's just overkill and possibly a crutch for bad musicianship or lazy directing.

I suggest taking a look at the dbx 1046. I have not used one, but it looks like four decent compressors in one chassis. Not the cheapest but it probably performs better. I also like the idea of going with a digital console if a change there is in the offing.


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## temper (Jan 23, 2013)

So I take it no one would be recommending running the main mix through a compressor just to take off the transient spikes? Instead, compression on each channel? 

A digital board like the x32 is definitely very tempting. I went up and took a few measurements yesterday and where the mixer would sit is 30" x 20" with a wall at the back and one side, and a restructuring of the space is out of the question for at least a year or two. So, unless I go with a digital 16 channel mixer, ala presonus, most anything larger than a small format 20ch mixer is going to be a tight squeeze. Ah, the limitations we find ourselves with sometimes....

So for future planning a digital mixer is definitely a strong contender, say maybe 2-3 years down the road. As far as an intermediate stop gap, is there anything you guys would recommend especially considering used gear is so cheap atm for analog outboard stuff?


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## museav (Jan 23, 2013)

On the four options:

1. I agree that a compressor on the master will respond to the overall mix levels and that any compression applied as a result will apply to everything. Not only can a single loud source end up compressing everything else but a widely varying source can also cause the compression to kick in and out. This may be a viable approach if you are trying to control the overall dynamics but it sounds like you are really trying to address specific sources.

2. I am pretty sure the CFX16 does not have inserts on the subgroups so that looks like it may not be a viable option.

3. You do have channel inserts but they are before everything but the preamp trim and high pass filter thus you would be compressing the unequalized signal and sending the compressed signal to monitors and EFX. However, this may be the best option should you want to add compressors.

4. Do you need compression on all channels? You noted wanting to avoid having to modify the connections at the mixer so don't you typically have just a few specific channels that would have the dynamics issues defined? Do you risk compressing signals where that is not desired?


How do I put this nicely... you seem to be describing challenged performers and less experienced volunteer operators so you may want to consider reevaluating the "creative theater work" until you can get all those involved to an appropriate level and/or can establish expectations that fit the resources available. I'm not saying that technology may not be able to help but I do get concerned that relying on additional technology in such situations can potentially create more difficult situations if anything unexpected happens.

Based solely on past experience, I also wonder if there may not be factors contributing to the issues being experienced such as insufficient stage monitoring, loud sources on stage or the stage/room acoustics. It's usually more effective to correct things at the source than to try to literally 'fix it in the mix'.


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## rocksure (Feb 1, 2013)

Compressors in the hands of people that don't know how to use them are about the best way to kill sound. I've been in churches where that is exactly what happens. A sound volunteer who doesn't know what they are doing, and has compression set all wrong can make it sound worse than if there was none at all. In the hands of someone who knows how to use them, they are a great tool. But where volunteers with only rudimentary knowledge are the name of the game...I'd be inclined just to have them across subgroups, and set up as limiters, with a high threshold setting so that they are basically only catching excessive peaks rather than compressing the average signal. Get someone who knows what they are doing to set them up and do the sound one Sunday, Then set and forget them.......and tell the novices to leave them alone. If you get compressors that also have expanders/gates then that can add to the problems if someone sets those wrongly too.


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## TimmyP1955 (Feb 3, 2013)

Morte615 said:


> Not normally the way I would recommend it but you could get a decent compressor/limiter and run it through the effects bus on the mixer. Set the compressor kinda high and then set the individual channel effects to use the amount of compression you need. Not perfect (not even really good) but may work. I've never tried something like this so not sure if it would work at all.



Nope. This is not how compressors work - a compressor is a serial device, not a parallel device (except in very specialized cases).


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## TimmyP1955 (Feb 3, 2013)

On most if not all analog consoles, whatever is inserted into the channel affects the channel's monitor send as well as the house send. This is not good - at least with most vocalists. A few mixers have internal jumpers to fix this. Most digital consoles can fix this with the push of a few buttons. These days, with the StudioLive and X32 families, I can't see going analog with outboard compressors.


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## museav (Feb 3, 2013)

TimmyP1955 said:


> On most if not all analog consoles, whatever is inserted into the channel affects the channel's monitor send as well as the house send. This is not good - at least with most vocalists. A few mixers have internal jumpers to fix this. Most digital consoles can fix this with the push of a few buttons. These days, with the StudioLive and X32 families, I can't see going analog with outboard compressors.


A good point about the post-channel processing aux sends but it can vary from console to console and the best idea is to verify it for each specific mixer. It should also be noted that parallel compression is not that uncommon but if you run channels to the effects bus for compression and do not also run those channels direct to the main mix bus then it would not really seem to be parallel compression.


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## jkowtko (Feb 3, 2013)

For light use, you might try starting out with 4xMDX4600, get one better (DBX?) 2-channel compressor to use for more demanding applications, and move your way up over time.

For my earlier analog applications I used the MDX4600, bought them all used ~ $60 each ... and still have a couple of them around. They worked well for light use, eventually started getting noisy, but for the use I got out of them it was well worth the investment.

I am running digital now, and for most vocals and orchestral instruments I'll use the compressors to soften those transient peaks. this means a starting point of around -10 and a ratio of maybe 2.5:1. This makes the volume levels on both instrumental and vocal solos a bit easier for me to manage on the fader bank.

Fyi a lot of mid-to-high end wireless mics have compressors built into the receiver. If you have any of these you may not need compression on those channels.


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## Jadams639 (Feb 8, 2013)

I think you should get a DBX DriveRack pa+ or PX , it replaces a limiter, crossover, Pre EQ, Parabolic EQ per out, an Easy Over, and an auto EQ That will get your system sounding dynamic and responsive walst providing the compression you want.


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## museav (Feb 9, 2013)

Jadams639 said:


> I think you should get a DBX DriveRack pa+ or PX , it replaces a limiter, crossover, Pre EQ, Parabolic EQ per out, an Easy Over, and an auto EQ That will get your system sounding dynamic and responsive walst providing the compression you want.


Or make it sound terrible and result in equipment damage, devices like the DRPA have to be properly applied and improperly applied they can be more of a detriment than a benefit. The DRPA and DRPX are also not the easiest boxes to adjust on the fly.


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## Jadams639 (Feb 9, 2013)

Yes, that's why I like to have a graphic EQ upstream of it for fine tuning from the booth, if he spent a few hours reading the manual and setting it up properly with his equipment there shouldn't be a problem.


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