I got 6.5 powerbass speakers in the door, 6x9 powerbass in the back rack. I drive a 95 maxima. Everytime the volume gets pass 18 in volume, the speaker get all crackly.

Please Help me?

 

what typer of radio are you running? sound like the impedence is too high? or not enough power to getting to the speakers. If you run a low wattage radio to high power speakers then you are going to get static or clipping because not enough power is being supplied

 

Its running off the head unit. The head unit is a kenwood. What do you think i should do?

 

I would double check all of your connections. If the connections are week, when you turn up the head unit, it will actaully cause small arcs across your connections because too much current is trying to be pushed through and your speakers will crackle. I've also seen the wires that run from the speaker cone to the speaker terminal block break, causing loose connections, causing arcs, causing crackles.

Do all of the speakers sound like this, or only some?

 

all speakers

 

If you are like me, and love to listen to loud, clear, powerful-sounding music, most, if not all, aftermarket headunits do not have enough power to listen to music at high levels. Aftermarket speakers are designed to handle more power than any single headunit can supply. Your answer ----- get a decent amplifier to power your speakers.

 

Exactly, a decent 4 channel amp will solve this.

 

If it's all speakers, I would agree that the amplifier is to blame. You can try backing off the bass a bit though. The bass notes are when all of the current flows through the amp and speakers. It will drain the small capacitors in your Kenwood quick (I agree that its not designed to supply as much power to your speakers as you would like) , causing a destabilization of voltage in the power rails of the amp, which cause the crackling.

But, in all honesty, the feeling of your chest cavity vibrating is what a lot of people crave, so either get a four channel amp like suggestted, or let a subwoofer handle your low frequencies, and install high pass filters on your other speakers (some headunits can high pass filter the speakers through their settings).

[Edit] If you are going to amplify your speakers that you already have, the four channel approach, I would recommend you buy a Class AB, or push-pull, amplifier, using bipolar junction transistors. This design is better suited to cover the entire human hearing range. A MOSFET amplifier is better suited to low frequencies because MOSFETs are slower that BJT (Bipolar junction transistors), but they can handle more power, which makes them attractive for subwoofers.