t-rue..... look... multiband compression... like said above, you get a mix... say the bass is booming a bit, you can filter out a bass frequency band-width, and apply some gentle compression to force it's DYNAMICS down relative to the rest of the mix.... or for the 1-4k area say.. mebbe it's too prominant IN IT'S DYNAMICS, again you can scour the band out, flatten it's DYNAMICS down a tad.... but if you apply compression to the mid band where a quantity of the snares dynamic's live, then sure!.. the snare WILL loose some of it's snap cos you're crushing it's DYNAMICS...
multiband compression isnt for fun!!... it isnt for tarting up a mix either!!... it is ONLY used to fix problems, the whole point of compressors used in this context is you SHOULDNT hear anything... it's pointless applying the compression until you can 'hear something' cos then youve gone to far.. if there's nothing to fix then you wont hear anything... thats the whole point...
the problem is, most people llsten to their stuff, and try to compare it to mastered commercial CD's most of which have had the loudness driven up to ludicrous levels removing any dynamic's at all in the ever-ending quest for 'instant-balls' - people get cd's from underground Brit artists and marvel at the depth of their CD's... simply, they work on the MUSIC, NOT trying to bang out something that sounds subjectively LOUDER & HOTTER than the competitors CD for cruddy FM airplay... it's a fucking plague to be honest nowadays cos everyone is just concerned about immeadiate loudness and impact...
So people get this idea that they have to fuck with a mix to 'make it better'... thats rubbish... if the track sound 'wrong' to you when played on all other peoples systems, then ask WHY it sounds rubbish?? - but dont ask WHY it doesnt sound like my CD's!!!!
make sure the eq & LOUD switch is flat when trying it on other peoples systems by the way - oh and NEVER EVER EVER mix on YOUR system with any eq or loudness switched In on your amp if you use a hi-fi amp that is -
ok... you try it on others' systems... is there too much bass?... or is the bass NOT consistant?.. is there sometimes peaks in the bass throwing the mix?.... then your mix is bass heavy OR the mix has peaks which exceed the overall bass DYNAMICS! - is there too much mid?... which bands?.. is it too sharp and trebly?.. again which bands?....
use eq to sort out these problems where the issue is the EQ itself NOT the dynamics... then you can use some enhancer mebbe to add a bit more sparkle to the whole mix etc.. but thats it... dont try to fix mix problems at the mastering point and DONT try to master your mixes destructively - always keep your master mix and a backup cos if you send it to a proper mastering house the last thing they want is YOUR attempt at mastering with compression so that they get a mix with everything fucked....
You say:
"even on low settings, the sound becomes "undefined", especially the snare drum... the snare loses all the crack and snap..
on heavy compression/boost settings, everything turns to mush, even though a particular band on SOLO seems might sound real snappy...
"
bravo!!!... now you're realising exactly what is wrong.... you're using compression where it's NOT required and totaly inapropriately cos THAT above is exactly what results.
what YOU need to do is first define WHAT is wrong with this mix if anything??... and ALSO define what exactly you are trying to acheive with this so-called 'mastering'???... tell us this first please -
if as you say: "I was trying to compress sub, kick, and snare on separate bands" - WHAT THE FUCK ARE YOU TRYING TO DO THAT FOR!!!?? - how on earth will that IMPROVE or in any way have any relevence to 'mastering' your track ? - is there something wrong with those elements ?...
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