I’ve recorded a couple of rock concerts recently using a Zoom H1 recorder which was placed in the room with the input set to around -8.0. The recordings sound great but I’m noticing that the volume is not quite as accurate as I remember it being so I’d like to apply some compression to it. Is it best to use the Compression tool that Audacity provides or a 3rd party once such as Chris’ Dynamic Compressor?
I understand that it varies on a case-by-case basis but are there any solid rules or tips/setting suggestions for compressing a concert? When I messed around using the compressor I was getting harsh fluctuations but I don’t know what I was doing wrong - For example, when a guitar was being played alone it was loud but as soon as the rest of the band kicked in the volume of the entire recording dropped.
I’m noticing that the volume is not quite as accurate…
I’m not sure what you mean by “accurate”.
Compression is one of those things you have to experiment with. There usually 3 different settings (attack, release, ratio) which gives you lots to play with, plus there are hundreds of different compressor plug-ins, each with their own sound.
You can also try the limiter.* (As with compression, apply make-up gain to bring-up the overall volume after limiting.) I did a couple of quick experiments with Audacity’s limiter and the current version set for “hard limit” seems to cleanly reduce “loud waves” without distorting the wave shape. With a live recording, I’d guess you can apply at least 6dB of limiting without any “damage” to the sound.
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Limiting is a kind of dynamic compression. If you buy a hardware compressor it’s often sold as a “compressor-limiter”. AVC, AGC and leveling are also kinds of compression. Clipping is a kind of compression (usually the worst kind …unless you like the sound of distorted guitar).
By “accurate” I mean that some parts seem unusually quiet. For example, one track features a backing track intro followed by the rest of the band kicking in a few moments later. When live, the backing track seemed almost as loud as the band but on the recording it’s noticeably quieter (Please see the photo where the play marker line thing is). So I was hoping to level out the difference between the peaks, preferably without hard limiting it, as a means to bring up the overall loudness (while avoiding clipping!)
So should I use compression and if so, should I compress based on peaks? Or should I use Chris’ Dynamic Compressor? Which is better?
cryano’s suggestion of the Envelope Tool is probably the best solution.
I’ve never used Chris’s Compressor and I can’t remember if it’s optimized for voice or music. But it wouldn’t hurt to try.
So I was hoping to level out the difference between the peaks, preferably without hard limiting it, as a means to bring up the overall loudness (while avoiding clipping!)
Just FYI - Audacity’s “hard limiter” setting won’t clip,* but it does “start” by affecting the loud parts and you mostly want to affect the quiet parts. (Most compressors work on the louder parts and then you use make-up gain to bring up the quieter parts.)
By “accurate” I mean that some parts seem unusually quiet. For example, one track features a backing track intro followed by the rest of the band kicking in a few moments later. When live, the backing track seemed almost as loud as the band but on the recording it’s noticeably quieter
That’s one of the reasons virtually all commercial recordings are compressed. The dynamics that sound good live at high SLP levels in big room don’t come across as well “at home”. The recording is linear (before compression) as long as you’re above the noise floor and below clipping… If there’s a 20dB difference between the loud & quiet parts live, there is a 20dB difference in the recording.
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There was an older version that did clip and the current version does have a “hard clip” option.
Chris’ dynamic compressor is optimized for music, especially classic one with a lot of dynamics. It’s purpose is to make such music audible “on the road”, i.e. amidst car noise.
It is rather an automatic gain control than a compressor. It has for instance no threshold knob (which every compressor has).
The provided threshold is only for the noise floor.
It might be ideal for your case though.
