[gijoe]

Alright, it sounds like you need some help.

The EQ, as you discovered, boosts or cuts at a particular frequency. The Q is how wide or narrow of a range that is affected. Think of the particular frequency as the top of the hill, or a flagpole. I high Q would represent the flag pole, and a low Q would be a hill. Does that make sense?

The high pass filter (HPF) is the point at which the high frequencies are allowed to pass to the speaker, but the low frequencies are cut out. I wouldn't set this below around 60hz even for a great pair of 6.5" speakers, 80hz is a safer choice for most speakers that size.

Speakers do not play the full audio spectrum by themselves, that's why we use subwoofers, mids and tweeters to cover the entire audible spectrum. The size of the speaker plays a very big role in how high or low it can play, the smaller the surface area is, the more excursion that is needed to produce the same output. Low frequencies require more output to sound as though they are at the same level as the high frequencies, so pushing a small 6.5" speaker down to 50hz is asking a lot. The 6.5" has to move a lot in order to produce frequencies that low. This much excursion can beat a speaker up quickly, the cone could be reaching it's limits mechanically, and the power required to do this could be causing thermal issues as well.

Even if you can play the speakers down to 50hz, the moment you turn up the volume, they have to work really hard. The more the cone moves, the more distortion you'll have, 50hz is subbass, not midbass. If you don't have a subwoofer to cover that area, be very careful about trying to use a small 6.5" speaker to do it. I wouldn't run even the best 6.5's that low.

Don't confuse a flat EQ setting with a flat response. Just because the EQ is set flat, doesn't mean that the acoustic response is anywhere near flat (and flat isn't the most desirable final tune anyway). Add a proper subwoofer, and stop using the bass boost. You may be tempted to get as much bass from those speakers as possible, but crossing them too low, and boosting them is only going to make them sound worse, and burn up quickly.