Power Issues with amps

[Sunriver61]

I had an JL Audio XDM700/5 and recently the front channels blew out completely. Only used about 6-7 times with no problems and then they went out. I was not pushing it either. Gains were <=3. Tested the front speakers which came in at 3.8Ω (Morel 63 VNC's) on the L&R. The door speakers came in at 4.2Ω Kicker 4x6's (limitations of a 60 year old car) and the sub came in perfect at 2Ω. I used the same 14g wire with the run <15' for the doors and 14g at 5' for the sub.

While this was in transit to JL Audio, I used a spare amp, RF R2-750X5 and got a power protect on it after about 10 minutes of testing. Power for the amp is a dedicated 12' run with a 60amp fuse block at the battery and also about 1' from the amp (long story, really hope that's not it...).

I also started to get a very soft hum through the speakers with vol @ 0 with the RF (but not the JL).

The amp ground tested at .2Ω (not thrilled with this but I don't think that should be a problem?).

Any ideas, recommendations, etc., would be most welcome - and thank you in advance!

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[1aespinoza 10+ year member]

Any ideas, recommendations, etc., would be most welcome - and thank you in advance!

Re-check the fuse holders. Make sure the contact points are clean and snug. Do the same with the ground points. The resistance test does not fully indicate the amount of contact. Your cable can be hanging by 1 thread and still show 0.2 Ohm.

 

[Sunriver61]

Re-check the fuse holders. Make sure the contact points are clean and snug. Do the same with the ground points. The resistance test does not fully indicate the amount of contact. Your cable can be hanging by 1 thread and still show 0.2 Ohm.

I can do that now just to remove a custom sidewall in the trunk...

 

[1aespinoza 10+ year member]

I can do that now just to remove a custom sidewall in the trunk...

Grounding point behind it?

 

[Mitchell Fosgate III]

Were those the recommended wires and cables by the manufacturers? Not enough volts to the amps and JL Audio. Humming sound and clipping. Cannot hear the sound really clear, fuzzy like sounds. Make your system uniform in Ohms. 4.0 ohms. Not different. Not enough volts going through it.