Help With Compression Effects

Hi everyone.

I was wondering how to use Compression filters. I have a couple free ones from various sources as well as the one that OBVIOUSLY came with Audacity lol but I never really understood how to use them.

Things like Attack and Release are kinda weird to me, Idk what they do.

Someone help me out please?

Btw, I’m mixing a track and I want the drum parts to sound like a Hi-Hop drum track with compression effects. How do I do that?

I also want the drum parts I recorded to sound fuller like Bonham from Zeppelin’s sort of playing.

Sorry if I asked too much lol.

Straight volume compression is pretty easy. Usually in a natural performance, you get louder and the performance as recorded gets louder the same amount. If there’s a compressor in there, sooner or later your volume increases are going to hit the Threshold Control. After that, you get louder, but the performance loudness doesn’t follow you as fast. The difference between the two of you is set by the Ratio Control.

Those two by themselves will give you a nice volume compressed performance that will sound like an airline pilot. Highly compressed sound by sound.

To avoid that, you use the Attack Control and Release Control. After you get louder, how long before the compressor wakes up and starts to do something about it (Attack). Then, after you go back to your normal playing volume, how long does it take for the compressor to stop trying to reduce the volume (Release).

You would think you would never want either of those two, but natural performances only work when those two are set–usually for each performance. You should take a live performance that you know very well and experiment with the tools. Don’t take a recorded performance because all of them have been messed with already.

As far as the other changes, those are combinations of equalization and other special effect tools. My fingers are tired.


One quick note. The tools in Audacity 1.3 are very much better than the ones in 1.2.


The standard compressor in Audacity can not be set with a fast enough attack for what you want - try the LADSPA SC4 compressor and set the attack to minimum.

Beefing up drum sounds usually involves compression, limiting, gating and EQ.
There is also a LADSPA “fast lookahead limiter” plug-in available

both of these (and many more) plug-ins available here:

The Limiter will very heavily compress the peaks (brick wall compression), while the compressor applies a more subtle compression. These both allow the “body” of the sound to be pushed up to much higher levels, However low level noise, reverberation and ringing will also go up, so a gate is used to truncate the tails of the beats.

I’ve not used the gate effect from that site, so I can’t comment on it.

If I ever get a recording mic kit for my drum set and record a beat or two, could you guys remaster it for me?

Just a question for the long run lol.

Maybe in a month or two I might do that.

I tried the Gate effect on some beats I had, I guess i’m bad with it because all I could do is reduce the DB level. Of course, that got rid of some of the dynamics I was going for though.

Idk how to ask it but how do I get a hip hop beat sound out of a drum track?

Like the smoothness of a hi hat in a hip hop beat meets the thunder of a snare drum (but not like Metallica where it sounds dead imo, a lively mix like Mitch Mitchell).

Sorry to ask such hard questions but I just wanna know what to do lol :smiley:.

A lot of Hip Hop artists just use other peoples samples.

If you prefer to make your own sounds, Compression with a fast attack and Equalization are the two main effects. Also, make sure that you have a good recording to start with.

Cool. I know about sampling and if done, it’s not bad but its not as fresh as I want it to be.

Fast Attack huh?

How do you go about getting a fast attack on compression?

Like how much should be the attack and release?

I’m kinda confused on that one lol.

Use the SC4 compressor - the standard Audacity (built in) compressor is not fast enough.
Set the attack as fast as possible (1.5 ms), and the decay to about 50 milliseconds (0.050 seconds)

The difference between RMS and Peak is quite subtle - tray it on both.

The “threshold” will depend on the amplitude of your original recording, but it needs to be quite a bit below the peaks in the recording.

The ratio can be quite high - try about 14:1

Knee radius quite small - try about 1 dB (larger for more subtle effect.

Make up gain - I prefer to leave this at 0 and apply Normalization or Amplification after the compression.

For a more aggressive sound (louder), also use the “fast look ahead limiter” after normalizing to cut the peaks down by about 6 dB.

Equalizing at different stages in this process will create different results. I usually like to have plenty of upper frequencies at the start (even with the kick drum). The lower frequencies will generally become more prominent after compression.

I’ve just knocked up a quick example of the kind of things that can be done.
The original recording:
Compression + Eq:
Compression + different Eq + Gate:
Note that NO reverb was added to any of these samples - all the reverb came from the natural reverb in the original recording.

Dude, thank you so much! I followed the compression step by step and I got it! Man, I wish I had people like you when I mix my stuff lol.

Whenever I make a song, can you please mix it for me? I’m not even kidding, those steps were so easy and awesome :smiley:.

You have skill lol.

Here’s the before and after of the Tribe Called Quest beat from the song, “Bonita Applebum”, that I was mixing with your advice:

  1. (Before):

  2. (After):

    Lemme know what you think. I kinda gave it a reverby effect too with the Black Water Reverb plugin I have. I kinda wanted it to sound like its in another room down the street with a little bit of a wet sound to it to make it plausible.

I know i’m not the best but I had a great time doing it. Man, I love these compressors. No wonder Hip Hop beats are always the best!

It may just be because you’ve down-sampled it for the internet, but the original sample has a lot of noise, which has of course come through on the processed version. It’s best to start off with a sample that is clean and high quality as possible.

You’ve certainly got the “in another room down the street” effect. There are a couple of reverb effects available as LADSPA plug-ins for Audacity: Freeverb and GVerb, both can give good results. My preference is freeverb, but it depends on what you like.

That’s the main thing :slight_smile:

I had a little go with your beat (just for fun).
I used “Gnome Wave Cleaner” (a Linux program) to reduce the noise before I started.
Then used the “Fast lookahead limiter” in Audacity.
Then converted to stereo (duplicated the track and set one to the left channel and the other to the right, then “Mix and Render”)
Then added some stereo reverb with Freeverb.
Finally, ran it through the demo version of “Click Repair” to remove some of the crackle that had been produced due to noise in the original sample.
Here’s the result:

That is a nice reverb you got there on your version.

Yeah, I got the loop from so it wasn’t the best quality. Never knew that downloading stuff ruined quality.

But I found my version got rid of SOME of the noise though cause of the threshold I think. But yours is great too. What is that reverb effect anyway?

I have almost every free effect for Audacity, including the huge pack they recommend + almost all the free VST plugins they have so lemme know so I can try it out :smiley:.