evilsim_LJ308

Help ... having trouble bridging amp.

Details : 4ch amp trying to bridge to run 2 x 10" subs from 4ch bridged to 2ch. Amp shows where to bridge chanels in series, but the protection LED flashes and gives no output? Tried wiring the chanels in parallel but same prob - protection LED flashes and no output?

Info : Amp = Specifications:
Powervox 4 Channel Car Amplifier
Output power (Max): 5600W (1400W x 4)
Output power (RMS): 560W (140W x 4)
Frequency response: 10Hz - 20KHz ± 1dB
Input sensitivity: < 250mv
Signal / Noise ratio: 98 dB
Separation scale: > 45dB
Stereo output: 2 - 16 Ω
Bridge output: 4 - 16 Ω
Power supply: 12V

Info : Sub Features:
10"x2 SUBWOOFER
P.P CONE FOAM EDGE
40 OZ MAGNET
4-LAYERS VOICE COIL(AL): 2"
MAX POWER: 2000W
FREQ.RESP.: 35-300HZ
IMPEDANCE: 4 OHM
SPL: 93dB/W/M
Weight: 18Kg
Dimension: 72(L)x 34(W)x 35 (H)

A picture ...

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Lina Mint LJ5000
Central QLD

evilsim_LJ308

mmm ... it's a tough one.

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Lina Mint LJ5000
Central QLD

Lucas' Deville

Polarity makes a difference when bridging ,ie ch1 + to sub(1), ch2 - to sub(1), ch3 + to sub(2), ch4 - to sub (2), rca inputs should be same with spliters for ch1 together with ch2 then ch3 together with ch4. Sorry, tried to make it sound easy. If you have done it correctly check channels 3 and 4 separtly to see if there's an internal short. Not a good idea to mount amps on sub boxes either, amp gets hot and sub vibrates the internal soldier joint apart.

Lucas' Deville

Also if you have a multi-meter set it to 'ohms' and check the resistance of each sub. The should be around 4ohms, if below 3ohms the coils drying out and can cause your amp to cut out to protect it's self.

evilsim_LJ308

Cheers Lucas have given me some new idea's.

When I hooked ... bridged I did it as you discribed and amp overloaded. I am gonna try each speaker separately with its channels to pin point if possible.

Also my idea is to maybe hook subs in series and bridge all 4 ch ... is this possible ???

Thanks Simmo

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Lina Mint LJ5000
Central QLD

v8tfcorty

What are the actual model numbers of the amp and subs ??

Crunchy_NuT

having the subs in series as you say should be the way to go - all 4 chan's going to the 2 subs should set up ok -- but then if you look at it from a sparky point of view - should be ok if 2 chans did one sub and other 2 for the other sub - cant understand why it wont work for you, did you get it brand new or second hand?

Lucas' Deville

Crunchy has it right mate. You can't connect all channels in series then in parallel because the first 2 channels are running off the same rca input (being left or right channel) and the other 2 channels off the other, there would be conflicting channels polarity wise and the amp would short and cut out. The sub should work off 2 channels bridge with no problems. Like i said get yourself a multimeter, stick it on ohms range to check the sub, if it reads 3-5ohms the subs fine and your amps stuffed. If you don't have a meter disconnect the subs completly from the amp and leave the rca's plugged in, and just drive around for a bit then check if it's cut out or warmed up, if it has your amp has an internal short, throw it away. A common problem might also be your earthing. Be sure it's connected securly to the chassie via a large bolt and that the paint between the bolt and crimp are clean.
Good Luck