Need Some Help With Compression

[Emerica167852]

So ive got some compression plugins, ive just been using the presets with them and they sound fine. but i dont really know how to set it.

like..

 

What does the two numbers in the ratio mean... and what would be a small ratio vise versa

 

and anything else that would help me out with compressing.

 

 

thanks:thu:

[Lee Knight]

Here's a simple explanation of compression. Compression turns down the loud bits of a sound so you can turn the whole sound up louder. Think about it. If you make sure that those bits poking out in volume don't poke out... then turn up the sound, the lowest, quiet bits will be louder.

 

The breath of an inhaling vocalist. His whisper. The subtle pick work of a funk guitarist. The sustain/decay of a bass guitar note.

 

So before talking about "those 2 numbers" (compression ratio, 2:1, 5:1, etc), look at the Threshold control. Picture the threshold control like the surface of the water. There's stuff under water, and above water. There's sound below the threshold and above the threshold. Sound above the threshold gets turned down (so you can turn the whole thing up, remember?). It gets turned down but it's still louder that the softer parts of the performance.

 

You get to set the threshold wherever you want it. Say you want to stop that distortion when the singer goes from " la-dee-dah" to "WHAAAHGGHGHGH". Then you set that threshold higher than his regular singing and just where the scream goes over it. And that scream isn't so loud now cause you're "compressing it". Turning it down.

 

Say you want to hear his whispers. Then you lower the threshold (think about the surface of the water), you lower the threshold into the regular part of the singing and that in effect turns even more of his performance down. So you can turn the whole performance up, right? And that, in effect turns up his whispers.

 

The more you compress (turn down the loud bits), the more you turn it back up so the loud bits return to the original volume. ???? So you in efect turn up the quiet bits. Turning it back up is done with the Gain slider. It's called Makeup Gain. You make up your lost volume.

 

So those 2 numbers? 3:1? 2:1? 10:1? That's the compression ratio. That is how much you want to turn down the sound after if goes over the threshold. After if comes from under water to up and over the surface of the lake. Do you want to keep the sound from getting any louder once it goes over the threshold? That would be 10:1 or even higher. They call that limiting. Set your threshold high so it just grabs the peaks of the sound but once they go over, they just stop right there. Limiting.

 

Lower you threshold into the sound more and lower the ratio, all the way down to 2:1. Now, whatever portion of the sound goes over the threshold gets turned down just a little. The loud and the soft parts of the sound aren't so far apart in volume. So you can turn the whole thing up louder. This setting effects more of the performance but effects it less.

 

Picture painting a man's hat bright green. Or painting all his clothes a very light shade. That's one way to look at limiting verses mild compression.

 

There are some great resources for better understanding what 2:1 actually means in specific quantity, how the math works, but the important part to remember is...

 

Under the threshold, the sound is unchanged.

 

Over the threshold, it gets compressed. How much it gets compressed is determined by the ratio.

 

You compress to turn down the loud portion of the sound so you can turn up the whole sound.

[kazumdb]

Here is a link to a pretty good paper by DBX.

 

ftp://ftp.dbxpro.com/pub/PDFs/WhitePapers/Compression%20101.pdf

[Ethan Winer]

 

i dont really know how to set it.

 

 

This is very short and right to the point:

 

Compressors and Limiters

 

--Ethan

[WRGKMC]

The main results of using a compressor is to decrease dynamics. When you record music and have guitars that are overdriven and have reduced or monotone dynammics. They basically have littel change in volume when struck hard or lightly. Getting them to blens in a mix with other instruments like drums that are highly dynamic is a big challange. Drums may spike above all other tracks when struck but quickly get buried by other instruments that have less dynamics as the volume impact dies.

 

This is where a compressor can be the most benificial. By reducing the initial attack and sustaining the time the sound drops off, you can make it blend better with other instruments that do the same.

 

Getting the attack time and decay set right so it cant be heard working is the trickey part. You want to get the attack ramps working together between tracks so the peak punches match. Set improperly makes the whole mix sound like mush having several peaks happening within a few miliseconds makes it sound like a wide peak and will kill any kind of impact the beat has.

Too long of a decay is bad too, it may not completely die out between beats and prevent the attack from doing its job, therefore just act as a volume booster or limiter.

 

Set too short on both attack and decay can cause rythmical volume swells. This is called pumping and breathing by many. The timing and threshold are likely misadjusted and too much compression is being used.

 

Using a compression is a trickey deal and you do have to experiment with them to understand how they work, where they will work best, how they can affect the tone of the music, and how they can increase unwanted noise.

 

If you create a mental picture of a hand on a volume knob, thats a compressor. The attack is how fast the hand turns the volume down, the decay is how quickly the hand turns the volume back up. The threshold is how much the volume gets turned down to prevent the volume from going into the red. The knee is weather the volume gets turned down sharply or gradually as it peaks.

 

How a compressor can be set depends on the attack and decay of teh sound coming from an instrument. A snare is sharp and fast and will make VU meters jump fast and high. A setting for it may be a fast attack and long decay. This extends how long the strokes will be heard along with the other instruments. It also prevents the sound from poking your eyes out when cranked up.

 

Something like a bass will suffere from dropouts if an inexperienced player doent have a consistant pluck to the strings. The bass string is slower to ramp up to a peak volume because there more mass inertia of the fat strings. Having a longer attack time to lower the notes peak volume or leave the poorly hit note amplified and unchanged thus nmaking the two notes volumes more even.

 

Something like a guitar rarely needs compression. Most guitarists will already have overdrive, compressors, and tube amps which wont need compression and can be the zero reference for adjusting other instruments. I find a longer attack, fast decay and higher ratio can be used on a cleaner guitar so it matches with an overdriven highly compressed one making the two blend better in many cases.

 

This is a good place for a note. The more drive and compression a guitar has, the more difficult the other instruments can be to hear or mix. The best you can do is narrow the instruments frequency range and give it that 80s boston sound so it lets other instruments come through the mix.

 

 

Vocals tend to suffer from attack issues and maybe splosives. Using a fast attack and longer decay can fatten and smooth a singers dynamics and make quieter notes and vocal trails be heard. Allows the vocals to be heard above the mix if done right.

 

In all these cases you would rarely use more than a 10:1 ratio. More likelyin the .1 for vocals or snare to 6 for kick and bass. If you cant get it right in those ranges, you got other issues that need to be examined.

 

The final thoughts are, If you hear a compressoe working you got too much.

Also keep in mind you dont need much. You can use multiband compression and limiters in the mastering stages to complete the smoothing out of the mix. using too much up front will only introduce noise later.

 

Compressors are very difficult to undo too. The opposite of a compressor is an expander. A thought would be to expand driven guitars so you dont need as much compression on others.

[TBush]

 

So before talking about "those 2 numbers" (compression ratio, 2:1, 5:1, etc), look at the Threshold control. Picture the threshold control like the surface of the water. There's stuff under water, and above water. There's sound below the threshold and above the threshold. Sound above the threshold gets turned down (so you can turn the whole thing up, remember?). It gets turned down but it's still louder than the softer parts of the performance.

 

 

Lee- that is THE coolest conceptualization of compression ever.

 

I wanna use analogy that when training my young Jedi son to mix...

[CN Fletcher]

 

So ive got some compression plugins,

 

 

Stop right there!!!

 

Go get yourself an inexpensive hardware compressor and learn how to use it. Not only do plugin dynamic range control devices sound like complete ass, they assume more knowledge of what you're trying to accomplish then 99.98% of their users have.

 

Learn hardware first and then the software bull{censored} might make more sense to you [or if it takes a really long time to learn, then maybe the plugins might catch up with something close to hardware].

 

I'd recommend you start with something like an FMR Audio "RNC" compressor... they're like $125- and sound 10x more expensive.

 

Peace.

[Beck]

. I'd recommend you start with something like an FMR Audio "RNC" compressor... they're like $125- and sound 10x more expensive. Peace.

 

+1000

 

I COULDN'T HAVE SAID IT BETTER...

[Cheese Grits]

The free manual for izotope ozone has a good discussion of compression: http://www.izotope.com/products/audio/ozone/OzoneMasteringGuide.PDF

 

If you want a simple hardware compressor, I recommend the DBX 166x. Couldn't be easier to use, and sounds pretty good to me.

[Warhead]

Fletcher is spot on, plug compressors are coming along but still furthest out from their hardware counterparts and learning on hardware first makes tons of sense.

 

War

[Cheese Grits]

The free manual for izotope ozone has a good discussion of compression: http://www.izotope.com/products/audio/ozone/OzoneMasteringGuide.PDF If you want a simple hardware compressor, I recommend the DBX 166x. Couldn't be easier to use, and sounds pretty good to me.

 

I just realized that I meant the 163x.