Setting Gains With Digital Multimeter

[MellowHype 10+ year member]

Yo im about to set my gains for my Alpine SPR-60c comps on my MRP-f600 amp using a dmm. I have learned most of what i need to do, however theres one thing im not sure of. The speakers take 110wrms at 4ohms, but my amp can only give them 100wrms. To work out what voltage i need, i use Voltage = SQRT(Power*Resistance), but do i use 100w, or 200 watts, as theres 100wrms x2, for the set of comps.

Also, I just went and checked my crossovers for the comps, and realised the tweeter level is set at -2 dB, does this make a difference to what tone i use when setting the comps??

Thanks for any replys!

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[trumpet 5,000+ posts]

How to Set Your Amplifier's Gain Correctly

I recommend you scroll down to keep_hope_alive's post and follow those instructions.

Use a 1 kHz tone for setting the gain for the speakers. You might find that you won't get enough voltage to reach 100 W before the speakers start to sound bad. You'll be measuring voltage on one pair of speaker outputs so 100 W is your number.

 

[MellowHype 10+ year member]

How to Set Your Amplifier's Gain CorrectlyI recommend you scroll down to keep_hope_alive's post and follow those instructions.

Use a 1 kHz tone for setting the gain for the speakers. You might find that you won't get enough voltage to reach 100 W before the speakers start to sound bad. You'll be measuring voltage on one pair of speaker outputs so 100 W is your number.

I used this and set my gains and my systems sounding alot better! Cheers

I need help with one more thing. Im going to get a Type R 1243d, and the RMS is 600, however im gonna get a 700watt amp - Kicker EX1000.1 . When setting my gains for this, do i go with the RMS ratings from the sub or the amp? because i heard these easily take over 700 rms so would i go with the 700 x 2 ohms = 1400, square root of 1400 = 37.41v, or the 600 rms rating from the sub? Sorry if ive not wrote that clear enough, and thanks for any replys!

 

[RoYALbLUE08 10+ year member]

I used this and set my gains and my systems sounding alot better! Cheers
I need help with one more thing. Im going to get a Type R 1243d, and the RMS is 600, however im gonna get a 700watt amp - Kicker EX1000.1 . When setting my gains for this, do i go with the RMS ratings from the sub or the amp? because i heard these easily take over 700 rms so would i go with the 700 x 2 ohms = 1400, square root of 1400 = 37.41v, or the 600 rms rating from the sub? Sorry if ive not wrote that clear enough, and thanks for any replys!

you should be good with that gain. i have my sub on 700 watts and i got the same sub as you but the 10 inch version swr-1043D.

although make sure you get a ported box. do not get sealed. sealed box sux balls and a ported sounds so much better and louder and makes your car shake like a mother. i know cuz i upgraded from a sealed box to ported 2 days ago and it made a world of a difference

 

[MellowHype 10+ year member]

you should be good with that gain. i have my sub on 700 watts and i got the same sub as you but the 10 inch version swr-1043D.
although make sure you get a ported box. do not get sealed. sealed box sux balls and a ported sounds so much better and louder and makes your car shake like a mother. i know cuz i upgraded from a sealed box to ported 2 days ago and it made a world of a difference

Alright thanks man!

And yeah im gonna go with ported, ive got a couple potential box's out of the 'free box plans' on here, i think im gonna go with this one, ImageShack® - Online Photo and Video Hosting - This is the second choice - ImageShack® - Online Photo and Video Hosting .

What do you think of them?

 

[RoYALbLUE08 10+ year member]

Alright thanks man!And yeah im gonna go with ported, ive got a couple potential box's out of the 'free box plans' on here, i think im gonna go with this one, ImageShack® - Online Photo and Video Hosting - This is the second choice - ImageShack® - Online Photo and Video Hosting .

What do you think of them?

cant really answer that lol im new to the boxes and tuning as well but im definately sure anyone of those should sound good. hell i have a temporary box from amazon by atrend thats ported until i have my custom box built (already have the box plans from mobile enclosure but im waiting to give him the go to build it till i gather up money) and this box sounds really good.

id wait for one of the veterans to asnwer that for you lol

 

[MellowHype 10+ year member]

cant really answer that lol im new to the boxes and tuning as well but im definately sure anyone of those should sound good. hell i have a temporary box from amazon by atrend thats ported until i have my custom box built (already have the box plans from mobile enclosure but im waiting to give him the go to build it till i gather up money) and this box sounds really good.
id wait for one of the veterans to asnwer that for you lol

Fair enough lol, im completely new to box's aswell but im gonna have a go at building one still as ive got someone that can help with the woodwork etc.

And yeah hopefully a veteran see's this then haha

Cheers anyway bro

 

[zako 10+ year member]

My observation with the previous generation of Alpine Type-R speakers is that their power "rating" is quite useless. They will reach their excursion limits much faster than the 110watt thermal limit unless you use a relatively high high pass frequency. On the other hand there are speakers rated for 70watts that will take a lot of abuse from a 150watt amplifier. So it's almost pointless to bother with a DMM to set speaker gains unless you know their _real_ power handling capability IMO. Simply calibrate the gains by ear and enjoy.

 

[maylar 10+ year member]

There is no standard for speaker power ratings. And the amount of power you can give any set of speakers depends entirely on the install and how low you want them to play. Using a DMM is a waste of time IMO.