Speakers Cut at High Volume

THe JBL's are 3 ohm impedance and the HU is not 3 ohm stable.

• Full Bandwidth Power: 21 watts RMS x 4 channels (at 4 ohms, 20-20kHz, 1% THD)

The most likely issue is you're causing the a HU to clip or cutout. Get yourself a simple 4 channel amplifier and you'll never look back. Full size speakers need power to power at even moderate levels, 21 watts (more like 15) per channel is not going to get you very far.

You should not continue to run 3 ohms speakers on a 4 ohm HU, you will burn up the HU amplifier at some point and could take your speakers with it. Something like these would be a HUGE boost and save the HU and speakers.


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You are clipping at the HU, and as stated.. will eventually damage the HU if continued. sounds like you need a little more power as stated. A 2 ch amplifier would work excellent for the need. Though.. It will be better to find a 4 ch to use for the money spent as you will find a better selection of amplifiers and pricing. This one will work really nice and pretty compact and an excellent make for the money. Look for an 8ga OFC amp kit as well should work excellent. That will put a stop to your clipping issues and save your HU from Frying,and give the speakers the power they need. This amp will run nice and cool with the gains down low and last you with 2 extra channels that you can later run a small sub if wanted to add