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Discussion Starter · #1 ·
I've never really had to do this before but just stuck an amp in my car with different speakers and test wired it. I only had output on one channel so changed the speaker over to see if speaker faulty or amp faulty . Now have no output from either speaker wired any way :( Have continuity at speaker terminals and correct resistance . What do I use to check the amp speaker output clamps ?
 

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There are two methods.
The first involves the use of a big resistor to act as a load, and a calibrated oscilloscope to measure the voltage across that resistor, having first shoved a sinusoidal waveform up its' input.
The second method is slightly less technical. You stick the amp in a car, drive to an electronics engineers place and get them to do it for you.
Not really feasible to test at home.
 

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Fruit & Nut Case
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Although i probably would have done the same as you, it sounds (no pun intended) as there is a short on one speaker or its wiring and you have now blown both output transistors. You say you have tested the resistance (i assume across the speaker wiring) the but it sounds as one leg is shorted to ground ?
 

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Discussion Starter · #4 ·
No shorts to ground unless internal on amp :) Resistance tested across the speaker terminal with no other wiring attached. Normally I'd simply pull a speaker from my spares pile and try that but none to be found. That's what you get for clearing up :(
 

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Discussion Starter · #5 ·
There are two methods.
The first involves the use of a big resistor to act as a load, and a calibrated oscilloscope to measure the voltage across that resistor, having first shoved a sinusoidal waveform up its' input.
The second method is slightly less technical. You stick the amp in a car, drive to an electronics engineers place and get them to do it for you.
Not really feasible to test at home.
Not a hope on either really, test cost would be more than amp cost new ! I'll see if anyone has a speaker hanging around I think
 

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Discussion Starter · #8 · (Edited)
Sorry not with you ? Speakers are 2 in a self contained box with just 2 external contacts marked + and - . Tested continuity and resistance across these 2 and had continuity and , as stated on speakers, 4 ohm resistance.

Both pods test the same , the one that did work from the amp and the one that didn't.

Amp is showing leds responding to mp3 input , pull that pin out ,or switch off mp3 and leds cease to respond.
 

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Discussion Starter · #10 ·
Cheers , I'll give it a try with fresh cable and Johns speakers :tup:
 

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Discussion Starter · #12 ·
Cheers John, I'll sort out getting over to you at some stage . Got to pick up a NEW fuel tank tomorrow so may do it then so you can have a look at it ?
 

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Discussion Starter · #14 ·
Well after borrowing bits from John found some time to check the amp ,wiring ,and speakers. Speakers wire is faulty internally :(
 
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