20 Most Recent Jl Audio 450/4 Car Audio Amplifier Questions & Answers

Nice amplifier. However it is best suited for speakers and not for sub woofers. Connect the plus (+) from speaker output 1 and the minus (-) from speaker output 2. Connect the plus (+) from speaker output 3 and the minus (-) from speaker output 4. Now the amplifier is in bridge mode, which will give you 300 WATT RMS at 4 OHM load. If you are bridging the amplifier to run sub woofers then do not forget to set the X- Over to LPF on the channels that you are planning to bridge. Whatever you do, make sure that the load you are asking the amplifier to play is no lower than 4 OHM. Playing this amplifier in bridged mode lower than 4 OHM is a recipe for trouble.
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ohms are impedance or the amount of current being blocked through the line. The lower the ohms the less resistance. Speakers run at a certain ohm (or at least are recommended to run at). Have you bridged your amp? Usually when you bridge your amp it lowers the ohms by half. You may have damaged something, especially if you bridged your amp and didn't bridge it properly.

Specs say it depends on the impedance of the speakers. https://www.jlaudio.com/products/jd250-1-car-audio-amplifiers-98360 https://www.google.com/search?q=jl+250%2F1+amp.+Wiring+diagram ..

sounds like the amps not rated for the resistance tha subs have it running at....are they a dual 2 or dual 4 ohm?is the amp rated for 1ohm? sounds like amps going into protect mode

Sounds like you either shorted something out or overloaded the amp. Is there any odor coming from it? If so It will need to be repaired or replaced. What did you have connected to it and how was it wired?

You will need to open it up to see if anything damaged. That does not look good at all from the outside.

In your world, what does best results mean to you. how are the hifonics mounted? open air, closed box, vented box (optimized to what freq)? trunk or inside vehicle? all these variations weigh heavily on your configuration. As does what 'best results" means to you.

Check your ground to make sure it is properly grounded

Disconnect all the speakers one at a time and see if it stops doing that, if it does you have a shorted speaker or wiring

Amps that big are usually fused on the feed wire, under the hood of the car, near the battery.

Re tune your amp

Check your speakers wiring to make sure they are not touching. This will make your amp go in protection mode.

Here's the Datasheet on the TDA7297 IC: http://pdf1.alldatasheet.com/datasheet-pdf/view/25110/STMICROELECTRONICS/TDA7297.html This should work for you. It also shows a recommended circuit for the part.