Help Me Do The Math

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May 23, 2016 | 08:10 PM

uplandpinter

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From: MN. USA

Help Me Do The Math

I am at the point of setting gains on my resent addition to my system. Math is definitely not a strong point and I have read the sticky that UN posted about setting with a DMM about ten times and still not ready to try it by my self.
The last time I set the gains by ear and thought I did a good job. Everything was good at first The front amp and speakers in the fairing sounded great and are still great after two years. But the rear amp and speakers in my bags only lasted about four months. So this time I am going to try the DMM method.

Here is what I have.

Fairing Amp= Cerwin Vega B4 600w
Rms 2ohm 150x4
Rms 4ohm 80x4
Frequency resp. 10-35 KHz

Speakers= Kappa 52.11I x 4
Peak 165w @ 4ohm
__________________________________________________ ___

Bag Amp= RZ4 2000d
Rms 160wx4 @ 4 ohm
Rms 250wx4 @ 2 ohm
Frequency resp. 10-35 KHz

Speakers= Kappa 693.9I x4
Rms 110w
Peak 330w
sensitivity 96db
2ohm
Frequency 35-30KHz

DMM Volt reading should be ??

May 23, 2016 | 08:17 PM

haze324

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Joined: Aug 2008

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From: S. FL

check the second to last page on that sticky. Slyedog posted a chart with the math done for you!

May 23, 2016 | 08:45 PM

myram

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From: ny

fronts are 150 w x 4 ohms =600
600 square root =24.49
rear 160 watts x 4 ohms=640
640 squared=25.29

May 23, 2016 | 09:28 PM

uplandpinter

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Joined: Feb 2014

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From: MN. USA

Quote:

Originally Posted by myram

fronts are 150 w x 4 ohms =600
600 square root =24.49
rear 160 watts x 4 ohms=640
640 squared=25.29

My speakers are 2ohm both sets.
So would it be

150w x2 =300 = 17.32sq
160w x2 =320 = 17.88sq

May 23, 2016 | 09:56 PM

haze324

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From: S. FL

for your RZ4.2000D check out the sticky by AAWAV where he benched that amp and make sure you use those numbers. The specs are a bit exagerrated.

May 23, 2016 | 10:11 PM

uplandpinter

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From: MN. USA

The specs call it 250w at 2ohm but AAWAY says more like 140w at 2ohm. I bought this amp from a popular member of this forum and was told that it would rock these speakers. Should I scrap it and start over? Or will it rock these speakers even at a lower wattage than specked?

May 23, 2016 | 10:44 PM

haze324

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Joined: Aug 2008

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From: S. FL

I can 100% assure you the specs from Power Acoustik are grossly exaggerated. That amp is the clone of the Soundstream PN4.520 and PPI 520.4. Same with the Soundstream PN4.1000D is the same as the Power Acoustik RZ4.”3000D” and PA once again exaggerated on the specs.

Honest answer -- that amp will push those speakers just fine, but the PN4.1000D or RZ4.3000D would do a better job. It’s also bigger and takes up more room. If you have it try it out and see how you like it. If you think you want a bit more than bump up to the bigger amp. If you don’t care about bag space the TN4.900 is the best one in that price range.