amp rms vs speaker rms

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greatone99

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if I use a 250 watt per channel amp with 120 rms focal k2 am I going to blow them ? the amp will run thru passive crossovers so I assume that will eat up some power.
 

The Car Stereo Company

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you will be fine. you can overdrive the speakers. it gives you dynamic headroom. to put it into prospective i have the mosconi as200.4 amplifier. 200 watts per channel. i use it as an active stage for my front speakers. 200 to the tweeter and 200 to the woofer. all of our higher end sq builds also use a 200watt per channel amplifier. you will have no issue with that power at all.
 
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greatone99

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you will be fine. you can overdrive the speakers. it gives you dynamic headroom. to put it into prospective i have the mosconi as200.4 amplifier. 200 watts per channel. i use it as an active stage for my front speakers. 200 to the tweeter and 200 to the woofer. all of our higher end sq builds also use a 200watt per channel amplifier. you will have no issue with that power at all.
even with 120 rms speakers ,now mind u I don't have the volume on 28 (29 clips on my volume dial) ,most I go is 21 -23 ,and stay on 18 mostly , also 250 is pro not reality ,that's at 14.4 ,in a perfect world
 

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even with 120 rms speakers ,now mind u I don't have the volume on 28 (29 clips on my volume dial) ,most I go is 21 -23 ,and stay on 18 mostly , also 250 is pro not reality ,that's at 14.4 ,in a perfect world
as long as your crossover points are set correctly, you wont have any issues. in the sq world, people are using much more power than that. two and three times the recommended power for speakers is not an issue. now there is such a thing as too much power though, but with what you are talking about, dont sweat it.
 

goblues38

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too little power is way worse the too much power....DISTORTION kills speakers....not too much power
 
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greatone99

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as long as your crossover points are set correctly, you wont have any issues. in the sq world, people are using much more power than that. two and three times the recommended power for speakers is not an issue. now there is such a thing as too much power though, but with what you are talking about, dont sweat it.
What do u recommend for test tone db -0, negative 5 or negative 10 to set gains .
 

goblues38

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test tone is not ideal...you need a pink noise generator and an RTA to do it correctly.

here's how I set Gaines. Gaines on amp all the way down....turn volume up to 75-85%%....ensure there is no clipping on input to amp (many amps have a meter built in for this)

Then put on many kinds of music and set gains to as high as you can go without clipping with master volume at 75%. Making sure you have your sound stage set....dash is a stage...rear fill. It is an art, not a science.

Doing it this way gives you some head room above 75-85%% max volume if you need it (quietly mixed cd for example).

Just get a bunch of music you know every beat, every vocal, every strum...and listen to it over and over and tweak until it sounds right to YOUR ears.
 
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greatone99

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test tone is not ideal...you need a pink noise generator and an RTA to do it correctly.

here's how I set Gaines. Gaines on amp all the way down....turn volume up to 75-85%%....ensure there is no clipping on input to amp (many amps have a meter built in for this)

Then put on many kinds of music and set gains to as high as you can go without clipping with master volume at 75%. Making sure you have your sound stage set....dash is a stage...rear fill. It is an art, not a science.

Doing it this way gives you some head room above 75-85%% max volume if you need it (quietly mixed cd for example).

Just get a bunch of music you know every beat, every vocal, every strum...and listen to it over and over and tweak until it sounds right to YOUR ears.
I have a dd-1 distortion detector , the head unit clips at 29 so I set it to 28 ,I used the dd1 tracks they have 2 at 0 , 2 at negative 5 , 2 at negative 10 , and 2 at negative 15 , I then played the tones thru the amp with speakers disconnected, and turned the gain till distortion light came on then backed it off till it unlit . To me absolute best way would be with an Oscilloscope
 
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