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I recently recieved this sub/amp setup from my uncle for my birthday. 600W MegaVox Competition Amp and 2 x 10" Marathon subs in a Marathon competition sub box. I have a 200W power supply that I used to test them as they are 20-25 years old. When connected to the 200W (12V @ 18A) power supply the subs could play sound (used an RCA to 3.5mm adapter that came with it) but was dropping out, which I assume is to be expected considering I was running a 600W amp off a 200W power supply. After this I installed them in my mates car ( AU Falcon, his wiring was all setup as he has subs of his own) by taking the wiring from his subs and connecting it to mine. When the car was started the amp powered up, but wasn't able to get any sound either from the head unit or the 3.5mm jack adaptor. Checked the voltage running through the power input and it read 14 Volts (normal as AU Falcons charge at 14V apparently). after fiddling around trying to get it to work i took them out and hooked them up to the power supply and it was back to being choppy but could still get sound.

 

Any help or insight into why I can't get sound from the subs in the car but can off a 200W power supply would be greatly appreciated

 

Cheers, Blake

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On 10/31/2021 at 10:40 PM, blakemcdonnell said:

I recently recieved this sub/amp setup from my uncle for my birthday. 600W MegaVox Competition Amp and 2 x 10" Marathon subs in a Marathon competition sub box. I have a 200W power supply that I used to test them as they are 20-25 years old. When connected to the 200W (12V @ 18A) power supply the subs could play sound (used an RCA to 3.5mm adapter that came with it) but was dropping out, which I assume is to be expected considering I was running a 600W amp off a 200W power supply. After this I installed them in my mates car ( AU Falcon, his wiring was all setup as he has subs of his own) by taking the wiring from his subs and connecting it to mine. When the car was started the amp powered up, but wasn't able to get any sound either from the head unit or the 3.5mm jack adaptor. Checked the voltage running through the power input and it read 14 Volts (normal as AU Falcons charge at 14V apparently). after fiddling around trying to get it to work i took them out and hooked them up to the power supply and it was back to being choppy but could still get sound.

 

Any help or insight into why I can't get sound from the subs in the car but can off a 200W power supply would be greatly appreciated

 

Cheers, Blake

IMG_20211031_223256.jpg

IMG_20211031_223336.jpg

IMG_20211031_223315.jpg

IMG_20211031_223357.jpg

Not sure why you have bridged the outputs like that.  The actual little wire in the middle isn't needed, and probably causes issues. Take it out and see what happens.

On 11/1/2021 at 10:18 AM, Ben C34 said:

Not sure why you have bridged the outputs like that.  The actual little wire in the middle isn't needed, and probably causes issues. Take it out and see what happens.

its the remote/switch input. bridged to power so that it turns on whenever it recieves power. will give it a try soon, just confused as it works fine with power supply but not in the car.

On 11/1/2021 at 10:38 AM, blakemcdonnell said:

its the remote/switch input. bridged to power so that it turns on whenever it recieves power. will give it a try soon, just confused as it works fine with power supply but not in the car.

also i thought it could be going into protection mode, but it doesnt make sense to me as the ground works perfectly on his subs and off the power supply both speakers work.

The amp is probably going into protection mode with the outputs bridged like that. That's not how you bridge channels together.

They do not act like AA batteries.

Also using that kind of wiring for power will cause more issues.

Also with the cost of car audio dropping exponentially, you'll be silly not to run a small footprint marine amp. Here's a fantastic one for the price.

The below amp would destroy what you have there in terms of power delivery, SQ, size, heat manage, etc.

https://frankiesautoelectrics.com.au/clarion-xc2410-400w-micro-size-4-3-2-channel-class-d-marine-amplifier/?gclid=Cj0KCQjw_fiLBhDOARIsAF4khR3wzCm4oVysGSSApkJvO81oVKIuGFZln-lEvBhk6526rHRAXp3pV8caAts8EALw_wcB

Clarion XC2410 400W Micro Size 4/3/2 Channel Class D Marine Amplifier

On 11/1/2021 at 10:08 AM, blakemcdonnell said:

its the remote/switch input. bridged to power so that it turns on whenever it recieves power. will give it a try soon, just confused as it works fine with power supply but not in the car.

That's not what I am referring to. There is a wire that shouldn't be there on the speaker outputs.

On 11/1/2021 at 10:56 AM, Ben C34 said:

That's not what I am referring to. There is a wire that shouldn't be there on the speaker outputs.

Righto man, cheers. Itll still run without that bridge on both outputs? or will i have to run another cable somewhere?

On 11/1/2021 at 10:41 AM, Dose Pipe Sutututu said:

The amp is probably going into protection mode with the outputs bridged like that. That's not how you bridge channels together.

They do not act like AA batteries.

Also using that kind of wiring for power will cause more issues.

Yeah, we were running 50amp wiring in the car this was just the setup we used for the power supply to test it as it was a spur of the moment decision. regarding the output bridging do i just remove the cable bridging the negative to positive and leave it? or do i run speaker wire's from both to the respective parts of the speaker?

 

as you can probably tell im very new to this sort of stuff haha, only time ive hooked up subs had a built in amp and just needed power, ground, remote and input. all other wiring seems alright though?

On 11/1/2021 at 1:41 PM, blakemcdonnell said:

so literally just take it out and it should be fine?

As in.....it won't blow up, which we're all surprised that it hasn't already with the way it is wired now?

Yes.

You should do a little google on what it means to bridge an amp, and how it is achieved, so you at least understand, rather than flying blind.

Then the next question, can you even bridge channels with that amp?

There are no physical markings saying you can bridge these channels.

 

Honestly, just buy that Clarion amp I posted up above. Cheaper than a car catching on fire.

On 11/1/2021 at 2:33 PM, GTSBoy said:

As in.....it won't blow up, which we're all surprised that it hasn't already with the way it is wired now?

Yes.

You should do a little google on what it means to bridge an amp, and how it is achieved, so you at least understand, rather than flying blind.

 

On 11/1/2021 at 2:39 PM, Dose Pipe Sutututu said:

Then the next question, can you even bridge channels with that amp?

There are no physical markings saying you can bridge these channels.

 

Honestly, just buy that Clarion amp I posted up above. Cheaper than a car catching on fire.

hahaha fair enough, this is just how i recieved them from my uncle. unless hes changed the wiring, this is how he ran it in the 90s. very confused as i cant find anything about the amp on google at all. i will probably end up buying that amp to be honest. what should i be looking for besides on google to see if they can be bridged?

Amps probably stuffed, might be a blown capacitor or three. So weird with that wiring setup, I'm surprised it worked haha.

Just get a Class D or mono amp (rated higher than the RMS of the subs, check impedance), save yourself the hassle.

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