Some tips for digital audio mastering
Mixing and EQ: how to achieve
that clean sound
OK, now I got a clean sound - but my trebles sound so harsh
Pure digital productions suffer from their absolute reproduction accuracy in a way that many such recordings sound harsh, metallic, and thin. We'll only scratch the surface of this issue here, to make a long story short: the imperfections of analogue gear, especially tape recorders, produce a series of non-linear frequency ranges and harmonic distortions that sound pleasant and warm to the human ear. Publishers of modern software and digital hardware gear put a lot of effort in emulating those flaws to achieve what is commonly referred to as
analogue warmth. The most obvious way to remove some harshness is to employ a tape machine emulation plugin. Treating your hi-hats, softsynths and other treble-heavy channels like that can work wonders on your production. Nowadays I tend to add subtle tape emulation or harmonic distortion to almost every channel, to get rid of that digital-esque sound and achieve a warmer output.
Exporting your mixdown for mastering in external tools (like Wavelab or Audacity)
Most modern Digital Audio Workstations provide useful facilities for mastering. But in case you wish to master your track in your wave editor, or if you wish for someone else to do the mastering for you, you'll want to send a high-quality, uncompressed wave file. Export the mixdown with 44100 Hz, and a minimum of 24 bit resolution to prevent digital noise or loss in dynamics. Don't use any master bus compression at this stage if you want to master in another tool! Do not export at higher frequencies, since the later conversion back to 44.100 Hz will be lossy. Hint: It's not necessary to run a normaliser based on maximum peak level, the final limiting/dithering unit should take care of that.