How to make music louder without it sounding rubbish?

[Katranat]

So this is probably a very silly question, but I have no idea how to google this properly so apologies if I come across as an idiot.

Does anyone with any audio editing experience have any idea how to make the volume on a music file louder without it sounding completely rubbish? I have some music I'm wanting to use for an AMV and it's absolutely fine, it's just a bit quiet. I'll use it anyways but it would be nice if whoever eventually watches the AMV doesn't have to crank their volume up to get a good experience.
Whenever I try to manipulate the volume the naturally louder parts of the music sound terrible - ie there's a lot of noise/static (I have no idea what the proper term for this is).

Any ideas? Is this possible? Or am I stuck with having to force people to turn up their volume?

[Kireblue]

If you buy your audio, the song should sound fine out of the box. If it gets lower when you edit your video, then the master volume control on your editing program is probably turned down. Either that or the render settings are messed up.

[Katranat]

It's classical music that I've ripped from a 90's CD, it's genuinely just quiet. Heck if anything it actually sounds a bit a louder when I listen to it in my editing program rather than when I listen to it using VLC or something.
My video for round 3 of POE used one of the tracks from this CD, so that's kind of an example of the volume level. You really have to crank it up to hear a lot of the nuances.

[Zarxrax]

See if your software has a "normalize" audio setting. That should raise the audio to the maximum volume without it causing any distortion. Classical audio is naturally a lot quieter sounding than modern music though, because there is a larger dynamic range between the loud and quiet parts. Modern music has really compressed dynamic ranges so there isn't much difference between the loud and quiet parts, so it just sounds louder.

[Katranat]

Yes it does! Thank you, I shall have a play around with that and see what happens

[Scintilla]

And if normalization doesn't bring it up enough (this is likely if the loudest part of the original recording was already pretty loud), then it's time to look into compression and limiting. Adobe Audition (formerly Cool Edit Pro) has a compressor that sounds pretty good as long as you don't get too extreme with the ratios (I wouldn't go over about 2:1 unless you use the soft knee setting) and a hard limiter that usually sounds fine as long as "Percent Clipped" is no more than about 0.1%, which you can "Gather Statistics Now" to get an estimate of. I'm sure Audacity has similar tools, and if your video editor accepts VST plugins then there's a whole host of free compression and limiting VST plugins to choose from.

I did something similar myself in 2005 for my AMV with Evanescence's "My Immortal", which didn't have nearly the dynamic range that you'll find in classical music, but still enough that I always wanted to fiddle with the volume when listening on my cheap 2.1 computer speakers and sought to prevent viewers from needing to do likewise. In retrospect I'm not sure it sounds better that way, and these days I would rather make listeners turn up their volume if it means retaining the emotion in the dynamic range, but that was pop; for classical music recorded on CDs you should have much more latitude.