bottom out

I have two 900 watt amps and two 12inch type R subs.  They want to bottom out at lower bass tones.  What would be causing this to happen?

1) What exactly do you mean by "bottom out"? 2) Which model Type R? There are at least 3 different ones that I know of. 3) What is the make/model of the 2 "900 watt amps"? 4) What type of enclosure are you using? Sealed, vented, bandpass...Squirrel

"No more Cpt. Kirk chit chat"

If its too loud, then you're too old

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The cone will overshoot and start hitting the frame and bottom out in the magnet's air gap

Well, the SWR-1241D's are 4ohm DVC's rated at 300RMS 1000Peak. The MRD-M500's are Class D amps rated at 500 x 1 @ 2ohms based on 14.4 volts, should be around 450 x 1 @ 2ohms based on 12 volts. You should have each sub wired in parallel to it's own amp like this for a 2ohm load per amp... You're not overpowering the subs with only 450 watts per sub, so the next logical step is to look closer at the enclosure. What size is you're vented enclosure, and is it a custom box or store-bought? What size/how many ports are there?Squirrel

"No more Cpt. Kirk chit chat"

If its too loud, then you're too old

Donate to the12volt.com

yeh, vented boxes are designed with a particular tuning freq. go lower and the box unloads and sub x-max goes exponential, very damaging to spiders/surrounds/cones/your back pocket,  also bass becomes non existent at freq below tuning freq. I need more power.....

emarald wrote:   also bass becomes non existent at freq below tuning freq.

not true the roll off of frequencys below the port tuning is much quick then that of a sealed box the bass is still there but not is not as loudwhoaaa