Id say recheck all your amp connections ( signal wire, 12V, ground, RCA inputs, and then the wires from the amp the sub) Something might not be in just right.
Also check you amp settings, you might have bumped the gain control or bass boost knobs.
If the 12V, remote wire and ground werent secure, then I don't think the amp would turn on. It does turn on, so I think these are connected well, but I will still double check.
Also, my amp has a cover screwed over top of the settings panel, so they cannot be touched unless I take the cover off.
I really hope it doesn't come to where you have to advertise giving people rep points just to get help.
Are you positive it's the subs? Have you put your head right next to it? I'm not sure what set up you have though.
And have you checked the adjustments on the amp itself? Such as the gain or volume? I would also double check your headunit. Maybe set it back to default settings and re-adjust.
You also may want to power cycle the amp. Disconnect the power and all the cables from it, and re connect.
Just a couple things I'd try first if it were me.
Yes, I am positive it's the subs and the adjustments haven't been touched. I also checked the headunit and all the settings are the same. I will try disconnecting it and connecting it again.
Check your ground wire and make sure that you've reconnected your speakers in the right polarity config. Reverse polarity can affect the output of any speaker.
This may be the problem, I will try switching them... would this be harmful?
change the speaker wire pos and negtive going into the sub like the one thats going into the red put it in the black terminal and vice versa
I could do this... but could it harm the subs at all?
I bet you blew the sub. Depending on the settings that were on your friends amp, may have blown it. The ohms or something wasn't right. Something similar happened to me a long time ago where I had a sub and amp setup and the sub blew so I went to the shop to get a new one, turns out they didn't have the same one but a different model so I got that one. Well the guys or me never changed the amp settings to account for the new sub and it blew the sub immediately.
Take the sub out of the box and smell the back of it where the magnet and coils are. I bet it smells burnt.
I'm almost 100% sure that they didn't blow because he has the same setup as I do and we tested his amp on my subs on very low volume. Could they still blow if we tested them on low volume?
If he melted a voice coil in one of them, that would explain why it sounds so low in volume.
Was your friend's amp smaller than yours? Just asking because low power and distortion is what destroys speakers.
Another suggestion, if your amp has built in fuses, check those. Sometimes hooking up the ground wire with the radio powered up will blow a fuse leaving you with only one working channel.
My amp runs 460 watts bridged and they can handle 400 watts, so I normally slightly overpower them. And I do crank the volume every now and then. His amp gives out about 400 watts, so it is basically a perfect match, but I did notice that he set his gain pretty high. I only played them with his amp on very low volume, do you think anything could be harmed with very low volume and a high gain? Also, I will check the fuse soon to see if that could be the problem.
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Anyway, thanks for all the help guys, +Rep for all of you. I will try your suggestions soon and update you after.