Verified answer

the subs should not be getting any high notes, they are made for the lows.

make sure that your crossover on your amp is on low pass, or the frequency knob is turned low (or on mid) not high

is the box itself too small

if the port holes are too big it would not let them play that low but they would be far from "high", and if its a prefab box the port holes should be fine (if you made -tuned- the box yourself you may want to double check your specs and dimensions)

It sounds like you are having a balance problem with the different frequencies. Most of the bass and deep rhythm sounds are between 60 and 300 hertz. Bass voice sounds are from about 160-630. I think you get the idea what an equalizer is for which is what you need to make your music sound better. The adjustments will determine the mixture of the different tones in music to your sound system. If you want lots of bass you move the levels for 60Hz-300Hz higher. Be careful that you don't move them to the point that it drowns out some of the other tones. Some equalizers are labeled differently for different frequencies, but with some practice you will be able to adjust the music exactly how you want it to sound no matter how it sounds originally. Good luck.

Here is how to get the right port sizes:

Port tube length calculations for round ports:

input = Radius of Port (R), tuning frequency in Hz (fb), Volume of the box in cubic inches (Vb), (L) will be the resulting length of tube.

L = (1.463 X 10^7 X R^2 / (fb^2) X Vb) - 1.463 X R