You have to start getting the idea of volume out of your head as being an abolute. Perceived volume is always a relative thing. I mean anyone can make something loud. Like, you've seen a volume knob and you know what it does if you turn it clockwise, right? ? ?
And you know that if you turn it too far and it sounds bad, you need to back off and turn it back to the left.
Alright, good ... glad we got that one out of the way.
Now on to loudness and perceived volume ... Keep in mind that you're getting in to some very broad concepts regarding economies of sound. I know that sounds like a stretch, so bear with me, but if you're economic and efficient about the sounds you're working with, then you'll have a louder-sounding finished product in the end. That's really the only way I know how to accurately describe it. And to get any further in to this is going to require far too much detail and explanation than anyone here will have time to post, so I would highly, highly suggest you start reading books -- like the Bob Katz book that everyone seems to like so much. What I'm trying to say is that this one might take a little more academics / book smarts. It's part art, part philosophy, but even more science than anything else.
As far as specific suggestions, the single biggest thing that comes to mind is arrangement. If you clutter your production and try to create a wall of sound with a million tracks, you may wind up with just the opposite effect and be left with a weaker-sounding production.
Another thing that comes to mind is really simple ... and that is to make sure you have plenty of midrange energy; guitars, vocals, piano, etc. Our ears are most sensitive to frequencies that occupy the range between 1K to 4k or so, so make sure your arrangements have plenty of that stuff "budgeted" if you want a loud-sounding mix.
Lastly, if you want something to sound loud ... then don't try to play or sing "louder." That's the last thing you want to do. For example: the bassist who picks really hard during "loud" parts of the song, or the guitarist who strums extra hard, or the vocalist who tightens his vocal chords and the drummer who smashes the daylights out of his loud cymbals.
Instead, try playing more deliberately and with controlled intensity. Think of it like this: What do you
really hear when a bassist plays "louder?" I know what I hear ... a bunch of "PINK!" "TING" "POP!" crap. Pure muddled crap, basically. Actually sounds a lot weaker than when he was playing 'quieter.' Now apply the same principle to the 6-string. Does picking extra hard
really make the chords sound more powerful? Or does it just make them sound choppier and less distinct? When the drummer hits the cymbals with great force ... does it really help matters, or does it just make the snare and toms sound much less powerful due to all the crazy cymbal bleed, etc ?
That's about all I can think of for the time-being. Good luck on your quest for loudness. I'm sure you're going to conquer the world with your sheer, unabashed raw volume in no time.
