MMATs 3000.1

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You can try it. Have everything clamped and a 10-15 amp fuse in the B+ line.

Before you begin, you should know that the replacement 4710s are a gamble. Some work and some don't. The IRF3701Zs are reliable but are rated lower than the 4710s. If the owner is like every MMATS owner around here and insists on running it below its lowest rated load, it may not be reliable.
 
Cool, I have a D100CH that I believe has the HIP4080 defective. Mine plays at low volumes on sine wave but only puts out 16-18v on the speaker terminals once I turn the gain up to get normal volume it starts to dirstort/clip pretty bad. But if I keep the speakers output at 18v or below it plays just fine.

I know these are 1200watt amps, and all my 500-1200watt amps always put out 32v-48v on sine waves. I just can't believe these one only puts out 18v, my speaker load was 2ohms then I tried 1-ohm which dont know if thats a problem since its rated for .67ohm but highly doubt it.
 
That doesn't really sound like a defective 4080. If it was defective I don't think you would get the amp to power on for long without damaging more components or going into protect.

If you want more help diagnosing your amp you should post a new thread and describe your problem, someone will most likely chime in and help.
 
You know what you may be right because now the freaking amp is playing at 22v and is pretty loud. What I did was left it at a 20hz low volume for 30min then did a sweep from 20hz to 200hz back and foward on my sinewave generator and now it seems to be louder.

Maybe it was just sitting in someones closet for tooo long???
 
Ok, I installed a new HIP4080AIP, installed new B4710s. The amp oscillates and plays nice and loud but it produces quiet hum through the sub woofers that is only audible at low volumes. It makes the hum without the car engine running.

I have 0v to ground on the RCA shields and .11v DC across the speaker terminals.

Here's the kicker, no other amp I have does this but when it is plugged into the RCA out from the highs amp the hum is very noticeable, when plugged directly into the RCAs from the HU it is A LOT quieter but can still be felt on the sub cones.

If I plug only one RCA into the amp it hums extremely loudly, doesn't matter which RCA cable or which RCA jack is used. When both RCAs are plugged in it quiets down, even if the second RCA's shield doesn't make contact, just the center lead, it quiets down.

If I use a Y connector and split the RCAs to the highs and sub amp, I get ground noise on the highs so I'm guessing that ground noise (engine running) is being produced out of the MMATS input jacks.

Any ideas?
 
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I didn't think there was anything operating anywhere near this frequency either.

It only happens when the RCAs are plugged in so I wouldn't assume the hum is generated by oscillation within the amp but just isn't being filtered out at the input.

Like I said before, if I plug the RCAs directly from the HU into the MMATS the hum is all but completely gone but since there is no output RCAs on the MMATS I used Y splitters to connect the highs. In this configuration I get ground noise on the highs.

It's as if I have a choice, ground noise on the highs with no hum on the subs (using Y splitter) or hum on the subs with no ground noise on the highs (using highs amp RCA out). The previous sub amp did not have these symptoms.
 
Not likely, the RCAs are held to the side panel with nuts.

One thing about this amp though is that there is no grounding circuit connected to the heat sink and no screws holding the PCB to the heat sink. The only way the chassis is grounded is because the RCA shields are bolted to the side panel.

I'll see what happens if I ground the sink to negative battery.
 
Not likely, the RCAs are held to the side panel with nuts.

One thing about this amp though is that there is no grounding circuit connected to the heat sink and no screws holding the PCB to the heat sink. The only way the chassis is grounded is because the RCA shields are bolted to the side panel.

I'll see what happens if I ground the sink to negative battery.




Not neccesarry because there are plastic insulators around the RCA's, but I did notice on mine that the heatsink is grounded to the ground terminal which are grouned with the transistors (dont know if thats how it suppost to be or if something on mine went wrong).
 
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