There's no hard and fast guide or rule when it comes to frequencies I'm afraid.
Try concentrating on 'tuning instruments' using EQ.
For example;
Snare drums:
1) Load a frequency analyser onto the track to assess the frequencies
2) You'll want to roll off any unwanted low rumble but without affecting the sound of the snare
-- Do this by solo'ing the track and loop a few snare hits, put a low cut with a steep Q (24bit), move the frequency up from 0hz listening to the sound of the snare, when you hear it clearing up then you're getting close, take it to the point where it adversely affects the sound (so makes it sound less good) and then lower it again to just under the point where it changed the audio, lower the Q (6bit). This will give a natural sounding low cut to the snare.
3) Look at where the sample is hitting the most (higher peaks in frequency EXAMPLE ONLY 170hz & 6000hz), these frequencies are where it's going to cut through the rest of the mix so they're important to bring out those elements
4) Using subtractive EQ'ing means to lower other frequencies other than the ones you want to affect, for example lowering the mids will bring out the lows & highs but without increasing the overall RMS of the sample and introducing unwanted noise from a positive EQ boost
5) Roll off any high frequencies in the same manner
I've take a print screen of an example here:
You'll notice there's also a little positive EQ boost but not much
I hope this helps
