Volume Inconsistency

[Curd]

I have a whole bunch of original mp3s spanning years.  Trouble is, the perceived volume is not constant.  Most were converted from audio tape, some done digitally, but few have maters from which to create a new mp3.

I'm wondering if there's some way to bring them all up to a similar level, using some sort of audio software.

My platform is Mac OS X 10.8.2

Any suggestions at all appreciated.

[T.C. Elliott]

You an use free VST plugins in any DAW to raise the level of a recording. A free limiter works really well. I'm assuming Garageband allows VST plug ins and the like. Does Audacity work on Mac?

At any rate, whatever DAW you use, find the limiter that comes with it or download a free one from the KVR site or somewhere similar and then put it on the master fader. Tweak to taste.  Let me know if you go this route and can't find a limiter that works. I can figure out the one I use the most (which still isn't that often) and get a link for it. It's easy to use and works okay for what you need.

[Farrell Jackson]

If Audacity works on a Mac, it's great way to non-destructively raise a songs level plus it's free. My process using Audacity on a completed song is to first raise the total volume to maximum. The I use Audacity's limiter to knock down the spikes with a value that does the job without squashing the overall sound too much. Then I raise the volume to the desired level. If I'm working with several songs of differing levels, I follow the same process for each but I still use my ears to get their final levels as close to one another as I can. This means Audacity again to raise or lower the songs until they match. I've not found that automatic EZ button to do this yet but I'm still looking for it, lol.

Farrell

[Curd]

Thanks guys.  I will look into your suggestions!

[HarmonicDistortion]

Does Audacity work on Mac?

============

Yes, Audacity works on Mac.   I have it on my 10.5.8 MBP.    Must confess however, I hardly ever use it.   I have Reaper (which I adore-  so much so, I actually paid for it!!)  on my desktop PC workstation in my "studio", as well as Audacity.   That's where I do my voodoo.

Assuming the Mac version of Audacity works the same (and as well) as the PC version, you can use it's tools to bring up the level of your old MP3's

[T.C. Elliott]

Just bumping up the master fader would probably suffice. Another note, if you compress the file and raise the level a couple of times until it's loud enough you won't get the huge limiting squash you can sometimes get with a hard compressor. It's generally a good thought to compress a few times at much lower levels than one time all hard and stuff, unless you've got huge spikes you are eliminating. Of course I use a limiter on most things to bring the level up because it's easier and I'm not releasing stuff as final products... yet.

[Puddleglum]

I have found that if you double up a quiet track, that is, put the same track on twice, the volume increases and it also gives it a thicker sound (useful if your guitar sounds a bit thin or drums a bit weak), you may have to twiddle with the volume a bit and then add a little bit of compression just to raise the the very quiet bits and squash any louder bits.