I came across this post at a different forum. It reminded me of all the threads here in which the OP asks about eq settings and is answered with "Run it flat" (which is good advice), or "eq to the room" (also good advice, but beginners don't know how to do that, and they're looking for tone options). So, I've paraphrased the post and put it here in a context for bass players. This link is also a very useful guide to eq. After reading the above links and experimenting a lot, and having experience playing live with loud drummers, I think I can offer some advice on how to achieve basic tones and how to run your amp in a rock band. This is how it works for me anyway, on my Peavey Tour 450 with a Precision bass. If you think I'm full of baloney and I shouldn't even be playing bass, much less giving advice, feel free to say so. Yes, these are bass mixing techniques, but they work in a band context as well, when you coordinate with the other players' eqs. They get you started on the signature sounds of the genres. First of all, forget about turning up your bass knob to sound "deeper". With most amps you're just going to get boomier, fartier, and more buried in the mix. The low knob on my amp has a center frequency of 50 Hz. The first octave, 40-80 Hz is felt more than heard, and it takes a lot of power to generate volume at low frequencies. If you are in a reggae dance band and you are lugging around high-power subs or plugging into a big pa, then yeah, turn the bass knob up a bit. I only use it for rolling back the boom depending on the room and the volume. The high knob on my amp has a center frequency of 8 kHz. I keep it centered, but I don't have bright speakers or tweeters. This knob is useful for rolling off the very top end for more of an old fashioned sound. Forget about dialing in giant swooping smiley or frowny faces on your graphic eq. It's going to sound weird. I'm going to avoid adding more than 6-9 decibels to any frequency. Most of the musical information we can hear as notes takes place in the midrange, and here one can use an equalizer to do a lot of tricks. You need a graphic eq or two bands of semi-parametric mids to try some of these sounds. We'll assume you're using a "modern" style flat and natural sounding amp. Amps that already have a character sound may not respond as well to these tips. These settings seem to work well for a p bass, adjust as necessary to your weird bass. Don't forget to adjust your gain between settings. Lower frequencies and spikes will generate distortion faster. I adjust my gain to just below where it starts to distort when I dig in. Your basic flat tone is a good start. Set all the tone knobs to center. If you have some kind of "contour" knob like I do, roll it all the way off. Compare the other sounds to this flat sound often, so you get an idea of how your tone is changing. My amp has an eq defeat switch which is handy for ABing. To get a little more punch in the low end, add 1 or 2 decibels at 100 Hz. Try it and see, AB it and really listen. We're still basically running flat here as far as to how hard the amp is working, but already we sound "deeper". If you don't play with a pick and you want to add some attack, add 3-6 decibels somewhere in the 2-4 kHz range. There are really many different kinds of "midrange scoops" depending on the frequencies. Your basic high midrange scoop can be used for a motown or reggae sound. Cut 5-6 db from somewhere in the 1-2 kHz (tinny) range. Now add some "mud" by boosting 3 db somewhere in the 200-250 Hz range. Add some bottom by boosting 1 db at 100 Hz. There, nice and warm and thumpy. For reggae or dub, go ahead and roll that bass knob up 2-3 db (that would be 1 o'clock on my amp). For a cleaner, more articulate sound use the low mid scoop. This would be used for country, jazz fusion (Jaco), or certain rock sounds (Entwhistle). Boost the tinny by adding 5-6 db somewhere in the 1-2 kHz range. Now, clean up the mud by cutting 6-9 db in the 200-250 Hz range. Add some bottom back for country or fusion by boosting 100 Hz by 1-2 db, or get a more aggressive sound by cutting 1-2 db from 100 Hz. A different, more modern sounding (Marcus Miller) mid scoop removes the "boxiness" instead of the mud by scooping 6-9 db at 800 Hz. Add the high mids, 5-6 db somewhere in the 1-2 kHz range, and add some bottom, 1-2 db at 100 Hz, just like before. This sound may not play as nicely with guitars as the low midrange scoop. Now experiment! Hope this helps.