Help a Noob with Gain Setting

[doublevision 10+ year member]

imma try to set my gain for my 2 amps. i have read through the gain tutorial thread and still have some questions i need answered before i attempt to set my gains.

1) i have an amp thats does 2x 200 rms @ 4 ohms mono BRIDGED. I want to give my speakers 150 rms each. so would the formula be

sqrt(150*4) = 24.49v ????????

when i bridge the amp, i dont have to do anything special with the formula rite?

2) I have a D4 sub being powered by an amp at 500 @ 2 ohms. which resistance do i plug in the formula? the 4 ohms of the sub or the 2 ohm load of the amp?

sqrt(500*4)=44.72v OR sqrt(500*2)=31.62v

3)would i still send a clipped signal from my amp to my sub if i underpowered my sub? or is a clipped signal only possible if you overpower your sub from its rated rms?

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[vario 10+ year member]

imma try to set my gain for my 2 amps. i have read through the gain tutorial thread and still have some questions i need answered before i attempt to set my gains.
1) i have an amp thats does 2x 200 rms @ 4 ohms mono BRIDGED. I want to give my speakers 150 rms each. so would the formula be

sqrt(150*4) = 24.49v ????????

when i bridge the amp, i dont have to do anything special with the formula rite?

No that would probably be okay.

2) I have a D4 sub being powered by an amp at 500 @ 2 ohms. which resistance do i plug in the formula? the 4 ohms of the sub or the 2 ohm load of the amp?

sqrt(500*4)=44.72v OR sqrt(500*2)=31.62v

Check how you wired the sub. That determines the resistance. To do this, take the multimeter and measure the resistance of the plus and negative wire that would run into the amplifier (Do not do this with any power running through and disconnect the two wires from the amp before) It should say either 2 or 4 I would imagine. You can't just send a particular resistance out of the amp, the speaker coil's dictate the resistance based on wiring. Your formula is correct assuming the D4 sub can be wired to 2 ohm and you wired it correclty to 2 ohm, you want 31.62, maybe a little less.

3)would i still send a clipped signal from my amp to my sub if i underpowered my sub? or is a clipped signal only possible if you overpower your sub from its rated rms?

Clipped signal is an amp problem. If you set gains correctly using the multimeter you will not clip the sub unless the amps are overrated garbage. It basically means the amp is working too hard to amplify a signal to a particular voltage. This causes it to the cut the top and the bottom off of the sound wave which distorts the speaker.

Giving a sub more power than rated and giving it too little power probably shortens the lifespan but its not the same as clipping the sub. I wouldnt worry about giving it too much power or too little power provided it is within +/- 100-200 watts rms anyway.

 

[nik 10+ year member]

3)its possible to send a cliped signaleven if you undrpower your sub,every amplifier have a max input signal if you give more it will clip

2)if your sub is dual 4 ohm & you wire your coils parallel you get a 2 ohm load so use this

1)its impossible for an amp to do 2x200 MONO BRIDGED only if its a 4 chanell both bridged, if so it works like you mention

 

[doublevision 10+ year member]

3)its possible to send a cliped signaleven if you undrpower your sub,every amplifier have a max input signal if you give more it will clip2)if your sub is dual 4 ohm & you wire your coils parallel you get a 2 ohm load so use this

1)its impossible for an amp to do 2x200 MONO BRIDGED only if its a 4 chanell both bridged, if so it works like you mention

3) what do your mean by max input signal?

1) yea i have a 4 channel amp that im bridging. so channel 1 and 2 are bridge and channel 3 and 4 are bridged.