port noise? distortion?

i got my new amp today, US amps xt2000D wired at 1 ohm, and installed it. it is powering 2 15" kicker cvr DVC 4ohm subwoofers. they are in a 2.9 cubic ft box (each chamber has 2.9 cubic feet), it is also ported. it seems im hearing some sort of noise come out of the port but, i cannot quite tell what it is. I'm not 100% sure what 'port nosie' actually sounds like, but it doesnt sound anything like distortion from the speaker (atleast i dont think it is). It just sounds like a little bit of wind blowing thru a hole or something (couldnt really think of anything else to describe taht sound, sorry). this sound comes directly out of the port, not the subs themselves. i also have them wired out of phase (which is going to be fixed tomorrow). any idea what this is?

Port noise.       But you may be OK tomorrow, the speakers being wired in phase will dramatically increase their volume, thus possibly masking the port noise a bit.

so wait, your saying that the port noise volume will increase? or my speaker volumer will increase?

thanks for the incredibly speedy response, idiot. i feel so bad when i say that

the gain settings and bass boost setting also seem to be limitless (as in i can turn it all the way, which i dont plan on doing very much) and i still dont get any distortion, could this be because of the out of phase issue? thanks.

He means that when you have your subs in phase you may not be able to hear the port noise any longer. How big is the port anyways? Port noise is caused by having a port with too small of a cross sectional area. Having the subs in phase should also help figure out what to set the gain to. You should be able to hear the distortion better. If you still can't hear it set the gain with a DMM.

ok, thanks for the clarification. im not exactly sure how big the port is (its just a shotty prefab box), ill meaure it tomorrow when i fix the out of phase sub tomorrow.

wishuponansg wrote: i got my new amp today, US amps xt2000D wired at 1 ohm, and installed it. it is powering 2 15" kicker cvr DVC 4ohm subwoofers. they are in a 2.9 cubic ft box (each chamber has 2.9 cubic feet), it is also ported. it seems im hearing some sort of noise come out of the port but, i cannot quite tell what it is. I'm not 100% sure what 'port nosie' actually sounds like, but it doesnt sound anything like distortion from the speaker (atleast i dont think it is). It just sounds like a little bit of wind blowing thru a hole or something (couldnt really think of anything else to describe taht sound, sorry). this sound comes directly out of the port, not the subs themselves. i also have them wired out of phase (which is going to be fixed tomorrow). any idea what this is?

Yes, that seems to be port noise you're describing.

Fix your phase issue, set your gain properly, and let us know if you still have issues.

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wishuponansg wrote: the gain settings and bass boost setting also seem to be limitless (as in i can turn it all the way, which i dont plan on doing very much) and i still dont get any distortion, could this be because of the out of phase issue? thanks.

 

The gain and bass boost were probably only causing more movement from your woofers.  No change in the sound at all.  Your woofers were out of phase, one woofer is canceling the other out.  Turn gain up and woofer A moves more, but so does woofer B, but in the opposite direction, thus canceling out the extra movement of woofer A.

Let us know if you can hear the port noise after proper phasing.

well i tried switching the pos. and neg. wires on one of the speakers today and had worse results. the subs seemed to be still out of phase, and were much, much quieter, and distorted much quicker (when setting the gains and bast boost). port noise was still there. the port noise is only noticeable when you put your ear practicaly in the port so im not to worried about it. are the subs going to be damaged if i cant fix the phasing problems?