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Discussion Starter #1
I have an Avionixx 440.4 amp bridged to 220rmsX2 pushing CDT HD642's. I tried setting my gains with DDM using the SQR(rms x ohm) came up with 29.6V. I the amp would shut off when I would get close to 10v. I settled on 7v. My sub amp a MB Quart ONYX1500.1. My battery voltage was holding a constant 13.8V. My HU had loudoff, flat EQ, volume set at 35/40. The Avionixx has always had a problem with what I assume is clipping out. I thought that is was supposed to be a good amp based off Elemental Designs.

I am thinking about replacing that amp. I have read that the components that I have are quite power hunger and need the full 250watts that they are rated for to sound off. I haven't found many 2 channel amps that have that much power and I read that bridging an amp isn't very good either. What should I do?
 

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Where are you measuring the AC voltage? On the input or output of the amp? The output should definitely be more than 7v AC.
 

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your voltage should be closer to 21. remember those are two independent channels now, your not getting 440 out of each channel, you're getting 220. 440 would be close to 30v.
 

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Discussion Starter #4
Yep 1k hz -0db test tone. AC volts on the out put. I set both gains at 7. I turned off the ignition and checked my resistance just make sure. It was 4ohms. my math was sqr of 220X4. My calculator came up with 29.6. I thought maybe I was doing something wrong but I came up with pretty reasonable numbers on my sub used a 50hz tone for it. I thought at was sounding a little distorted so I backed off. SQR 1000X2 came out to 44. I thought is sounded the best around 40. I was using a Fluke DDM so I trust the numbers.
 

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If your speakers are connected to the amplifier it will NOT be 4 ohms, it will be a fraction of a tenth of an ohm if the amplifier does not have speaker relays, and not many do.

If the speakers are disconnected reading DCR will give you less than the actual speaker impedance.... so in reality you should have never really seen the impedance you were looking for.
 

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Discussion Starter #6
The positive terminal and the negitive terminals are not connected except for at the speaker. If they are linked before that it would be a short. I know you don't want to check resistance on a live circuit. I killed the resistance of the speaker wire my stereo powered down. I read 3.8 or 4 ohms. I was a couple weeks ago. I can't remember exactly.
 
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