need help setting gain with DMM

[doublevision 10+ year member]

I have a couple of questions i need clarified before setting my gain with a DMM:

1) i have an amp that does 200x2 at 4 ohms bridged, so the voltage i should see on my DMM is 28.28v right? How about an amp that does 600rms at 2 ohms. the voltage would be 34.64v rite?

2) I only want my amp to send about 125rms to my speakers so would i change the rms in the equation? instead of sqrt(200*4), it would be sqrt(125*4). is this rite?

3) my amp have a birth sheet that say 732watts. Do i use that number instead of 600 in the equation?

4) What test tones should i use for my speakers? how about my sub? i was thinking of using an 80hz at 0db for both of them.

5) When setting the gain, what should my HPF be set on for my speakers. how about the LPF for my sub?

6) The LPF on my amp is always on but i would rather use the one in my headunit. how would i do this?

7) do i take the speaker wires out?

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[king ranch 5,000+ posts]

read the sticky in the amp section

 

[doublevision 10+ year member]

oh i didnt see someone reposted the tutorial at the end. thanx

 

[doublevision 10+ year member]

most of my questions have been answered by the tutorial but i still have a few questions unanswered.

2) I only want my amp to send about 125rms to my speakers so would i change the rms in the equation? instead of sqrt(200*4), it would be sqrt(125*4). is this rite?

4) What test tones should i use for my speakers? how about my sub? i was thinking of using an 80hz at 0db for both of them. i believe the tutorial mention to use 1000hz at 0db for speakers. how about subs?

6) The LPF on my amp is always on but i would rather use the one in my headunit. how would i do this?

7) do i take the speaker wires out? some people say to leave it in while others say take it out. which one is it?

 

[jco1385 5,000+ posts]

I have a couple of questions i need clarified before setting my gain with a DMM:
1) i have an amp that does 200x2 at 4 ohms bridged, so the voltage i should see on my DMM is 28.28v right? How about an amp that does 600rms at 2 ohms. the voltage would be 34.64v rite?

no, this is not what you will use

2) I only want my amp to send about 125rms to my speakers so would i change the rms in the equation? instead of sqrt(200*4), it would be sqrt(125*4). is this rite?

this is what you will use. you want it at a level to match your speakers, not the max output available

3) my amp have a birth sheet that say 732watts. Do i use that number instead of 600 in the equation?

no, thats just an actual output number from the factory. not really useful until you sell the amp (to show actual power output)

4) What test tones should i use for my speakers? how about my sub? i was thinking of using an 80hz at 0db for both of them.

for subs, i use a 40hz @ 0db. for mids i use a 1khz @ 0db. (thats just me, folks use different ones for different setups)

5) When setting the gain, what should my HPF be set on for my speakers. how about the LPF for my sub?

when setting the sub amp gain unplug the rcas on the speaker amp. same for the speaker amp (unplug the sub rcas)

6) The LPF on my amp is always on but i would rather use the one in my headunit. how would i do this?

what HU is it? if you have a "sub out" you'll want that all the way up when setting gains

7) do i take the speaker wires out?

yes, it's a good idea

^^^

 

[doublevision 10+ year member]

5) When setting the gain, what should my HPF be set on for my speakers. how about the LPF for my sub?

when setting the sub amp gain unplug the rcas on the speaker amp. same for the speaker amp (unplug the sub rcas)

i have one amp for my sub and another amp for my speakers. the amp for my sub have a built in LPF that i cant turn off. so what should i set that at? should i turn the dial all the way up or all the way down?

6) The LPF on my amp is always on but i would rather use the one in my headunit. how would i do this?

what HU is it? if you have a "sub out" you'll want that all the way up when setting gains

i have a Pioneer Avic n2.

 

[jco1385 5,000+ posts]

5) When setting the gain, what should my HPF be set on for my speakers. how about the LPF for my sub?when setting the sub amp gain unplug the rcas on the speaker amp. same for the speaker amp (unplug the sub rcas)

i have one amp for my sub and another amp for my speakers. the amp for my sub have a built in LPF that i cant turn off. so what should i set that at? should i turn the dial all the way up or all the way down?

6) The LPF on my amp is always on but i would rather use the one in my headunit. how would i do this?

what HU is it? if you have a "sub out" you'll want that all the way up when setting gains

i have a Pioneer Avic n2.

i'd set the LPF at the highest point you want the sub to hit, which is also where your mids take over. where are your mids crossed at? sub?

and idk anything about the options on that HU