amp and sub

05spectraSX · Post by **05spectraSX** » Thu Mar 16, 2006 5:51 am

hi, i am going to buy a 800 watt cable for an amp and subwoofer. If an amp maxes out 800watts, does that mean that only 800 watts will go to the subwoofer too?

Bwcad1 · Post by **Bwcad1** » Thu Mar 16, 2006 6:17 am

ur sub will most likely never see 800 watts from the looks of it you have cheap/budget equpiment. dont look at max ratings on anything there misleading and bull. look at the rms ratings there far more accurate.

05spectraSX · Post by **05spectraSX** » Thu Mar 16, 2006 11:07 am

i listened to the sub, it reaches around 700. but just in general if the amp puts out 800 does that mean it transfers only 800 watts to the subs?

Bwcad1 · Post by **Bwcad1** » Thu Mar 16, 2006 11:13 am

no. it doesnt and i dont think you or anyone can tell how many watts a sub is getting by ear. here is a good way to check output on an amp multiply the voltage of your car 12.6 if the car is off or 14.4v if its on X the amout of amps on the fuse thats what it is capable of producing there is a way to check wattage with a dmm and a clamp meter if you have them i can tell you how. if an amp is rated at 400 rms its putting out 400 rms if a sub is rated at 800 rms its putting out 800 rms if its rated max u have no idea go by rms not max. the amp only puts out so much power for instance my MM4000.1 produces 4000 watts rms bridged at one ohm so the sub will get 4000 watts

Bwcad1 · Post by **Bwcad1** » Thu Mar 16, 2006 11:17 am

Volts (measured at the speaker outputs of the amp) / amps measured off of the positive speaker lead about 6" from the amp = reactive load. Then take your (volts X volts) / reactive load and you have your wattage.

05spectraSX · Post by **05spectraSX** » Thu Mar 16, 2006 11:20 am

is there anyway to shut on and off an amp. like say you have a headache, and you don't feel like listening to thumping, but just the radio, can you shut the amp off? because i got a stock stereo so i can't electronically adjust. And the rms for the sub is 600.

plus if the package says an amp of 800 doesn't that mean that the output is 800?

Bwcad1 · Post by **Bwcad1** » Thu Mar 16, 2006 11:21 am

the sub doesnt have anything to do with power the amp produces the power the sub just uses it to move. put a switch on your remote wire.

05spectraSX · Post by **05spectraSX** » Thu Mar 16, 2006 11:26 am

what kind of switch and where can you get one?

Bwcad1 · Post by **Bwcad1** » Thu Mar 16, 2006 11:27 am

just a simple rocker switch will work and u put it right on the remote wire to the amp. autozone radioshack napa any will have them. digikey.com has them

05spectraSX · Post by **05spectraSX** » Thu Mar 16, 2006 11:36 am

i was testing out this subwoofer alpine i think from tweeter, and i put the volume up to 13 and i thought the sub was going to pop off or blow. The cone extended about 5 inches out, is that normal? it was only rated for 800 watts.