The EQ Bible

In the interests of passing along great information - here is a little guidebook, a bible if you will, to E.Q. settings for recordings. This article contains information originally sourced at EQ Frequencies and is used with permission from Songstuff.com. If you're familiar with working the knobs and faders to E.Q. your mix, this will be super-cool. If you aren't - this may be kind of a brain-drain, but nontheless - here it is:

50Hz
Boost: To thicken up bass drums and sub-bass parts.
Cut: Below this frequency on all vocal tracks. This should reduce the effect of any microphone 'pops'.
70-100Hz
Boost: For bass lines and bass drums.
Cut: For vocals.
General: Be wary of boosting the bass of too many tracks. Low frequency sounds are particularly vulnerable to phase cancellation between sounds of similar frequency. This can result in a net 'cut of the bass frequencies.
200-400Hz
Boost: To add warmth to vocals or to thicken a guitar sound.
Cut: To bring more clarity to vocals or to thin cymbals and higher frequency percussion.
Boost or Cut: to control the 'woody' sound of a snare.
400-800Hz
Boost: To add warmth to toms.
Boost or Cut: To control bass clarity, or to thicken or thin guitar sounds.
General: In can be worthwhile applying cut to some of the instruments in the mix to bring more clarity to the bass within the overall mix.
800Hz-1KHz
Boost: To thicken vocal tracks. At 1 KHz apply boost to add a knock to a bass drum.
1-3KHz
Boost: To make a piano more aggressive. Applying boost between 1KHz and 5KHz will also make guitars and basslines more cutting.
Cut: Apply cut between 2 KHz and 3KHz to smooth a harsh sounding vocal part.
General: This frequency range is often used to make instruments stand out in a mix.
3-6KHz
Boost: For a more 'plucked' sounding bass part. Apply boost at around 6KHz to add some definition to vocal parts and distorted guitars.
Cut: Apply cut at about 3KHz to remove the hard edge of piercing vocals. Apply cut between 5KHZ and 6KHz to dull down some parts in a mix.
6-10KHz
Boost: To sweeten vocals. The higher the frequency you boost the more 'airy/breathy' the result will be. Also boost to add definition to the sound of acoustic guitars or to add edge to synth sounds or strings or to enhance the sound of a variety of percussion sounds. For example boost this range to:
Bring out cymbals.
Add ring to a snare.
Add edge to a bass drum.
10-16KHz
Boost: To make vocals more 'airy' or for crisp cymbals and percussion. Also boost this frequency to add sparkle to pads, but only if the frequency is present in the original sound, otherwise you will just be adding hiss to the recording.
Specific Instruments
Vocals
General: Roll off below 60Hz using a High Pass Filter. This range is unlikely to contain anything useful, so you may as well reduce the noise the track contributes to the mix.
Treat Harsh Vocals: To soften vocals apply cut in a narrow bandwidth somewhere in the 2.5KHz to 4KHz range.
Get An Open Sound: Apply a gentle boost above 6KHz using a shelving filter.
Get Brightness, Not Harshness: Apply a gentle boost using a wide-band Bandpass Filter above 6KHz. Use the Sweep control to sweep the frequencies to get it right.
Get Smoothness: Apply some cut in a narrow band in the 1KHz to 2KHz range.
Bring Out The Bass: Apply some boost in a reasonably narrow band somewhere in the 200Hz to 600Hz range.
Radio Vocal Effect: Apply some cut at the High Frequencies, lots of boost about 1.5KHz and lots of cut below 700Hz.
Telephone Effect: Apply lots of compression pre EQ, and a little analogue distortion by turning up the input gain. Apply some cut at the High Frequencies, lots of boost about 1.5KHz and lots of cut below 700Hz.
Hi-Hats
Get Definition: Roll off everything below 600Hz using a High Pass Filter.
Get Sizzle: Apply boost at 10KHz using a Band Pass Filter. Adjust the bandwidth to get the sound right.
Treat Clangy Hats: Apply some cut between 1KHz and 4KHz.
Bass Drum
General: Apply a little cut at 300Hz and some boost between 40Hz and 80Hz.
Control The Attack: Apply boost or cut around 4KHz to 6KHz.
Treat Muddiness: Apply cut somewhere in the 100Hz to 500Hz range.
Guitar
Treat Unclear Vocals: Apply some cut to the guitar between 1KHz and 5KHz to bring the vocals to the front of the mix.
General: Apply a little boost between 100Hz and 250Hz and again between 10KHz and 12KHz.
Acoustic Guitar
Add Sparkle: Try some gentle boost at 10KHz using a Band Pass Filter with a medium bandwidth.
General
Try applying some mid-range cut to the rhythm section to make vocals and other instruments more clearly heard.

sub 0-60
bass 60-180
mid bass 180-300
lo mids 300-800
mids 800-2k
upper mids 2-5k
high end 5k up

Just remember these settings aren't magic, still use your ears and experience to get the type of sounds you want. This is just a general starting point or reference but by all means this isn't a rule to use these settings for those instruments all the time.