Hi guys,
I just got my sub back off a mate, and it's come home busted...
It's a 12" active sub for home theatre etc....
I plug it into the power and a loud hum is instant, even with volume all way down etc, and nothing on imputs etc...
I can't see any damage inside it, but i measured .5v across the speaker terminal which would be the cause... but unsure what to do or check from here...
Any help would be appreciated, as really want to save this sub....
Cheers.
I just got my sub back off a mate, and it's come home busted...
It's a 12" active sub for home theatre etc....
I plug it into the power and a loud hum is instant, even with volume all way down etc, and nothing on imputs etc...
I can't see any damage inside it, but i measured .5v across the speaker terminal which would be the cause... but unsure what to do or check from here...
Any help would be appreciated, as really want to save this sub....
Cheers.
Hi,
I have the same issue with a Misson M2S active sub. There was a power spike in my neighborhood and alot of electronics gave up.
If the sub is plugged in and turned on, the power light turns on and there is a loud hum in the amp and low vibration from the sub.
I haven't looked at it properly yet, but I know that the fuse did not blow. The issue is probaly a fauly power transformer and maybe the rectifier got hit too. I made a quick visual inspection and the internal amp shows no signs of fault.
trying to locate a schematic for it...
Mike.
I have the same issue with a Misson M2S active sub. There was a power spike in my neighborhood and alot of electronics gave up.
If the sub is plugged in and turned on, the power light turns on and there is a loud hum in the amp and low vibration from the sub.
I haven't looked at it properly yet, but I know that the fuse did not blow. The issue is probaly a fauly power transformer and maybe the rectifier got hit too. I made a quick visual inspection and the internal amp shows no signs of fault.
trying to locate a schematic for it...
Mike.
sub amp fault
Hi there,
remove your speaker from it's amplifier as any large dc will burn it's coil out and you'll need an new driver
Now if you can get a 10 ohm 10 watt resistor or higher watt type all the better because (1) if you have a meter set it to say 200vdc and connect the resistor and the meter in place of it's speaker load and repower up what reading are you getting now? it does no matter if the resistor get warm it saves you burning your speaker out.
You might have large dc the o/p thats why your hearing humm.
carry out some voltage checks, a balanced working amp will o dc on it's o/p.
Hi there,
remove your speaker from it's amplifier as any large dc will burn it's coil out and you'll need an new driver
Now if you can get a 10 ohm 10 watt resistor or higher watt type all the better because (1) if you have a meter set it to say 200vdc and connect the resistor and the meter in place of it's speaker load and repower up what reading are you getting now? it does no matter if the resistor get warm it saves you burning your speaker out.
You might have large dc the o/p thats why your hearing humm.
carry out some voltage checks, a balanced working amp will o dc on it's o/p.
faulty sub with hum
what is the dc voltage supply rails with in the circuit?
yes, you can use the old lamp trick a long with ac mains power in and all shows is there's a heavy load being pulled ie, a short.
You need to trace the fault ie, supply voltage or o/p short.............
What type of o/p device is in the o/p stage ic or transistors?
If there's transistors use your meter and read the base pin voltages if there's large voltage there the transistor is being hard switch on.
Faulty power o/p ic's need replacement as they can be damaged all to easy.
what is the dc voltage supply rails with in the circuit?
yes, you can use the old lamp trick a long with ac mains power in and all shows is there's a heavy load being pulled ie, a short.
You need to trace the fault ie, supply voltage or o/p short.............
What type of o/p device is in the o/p stage ic or transistors?
If there's transistors use your meter and read the base pin voltages if there's large voltage there the transistor is being hard switch on.
Faulty power o/p ic's need replacement as they can be damaged all to easy.
Sorry i'm posting on this old thread but I have the same problem and don't know how to fix it. As soon as the amp is turned on there is a loud hum. The sub is a jensen cs-10. Neither of the two fuses on the board are bad which made me think it was a problem with the fuse in the transformer. I figured i could just try to replace the transformer but I don't know how to find out what to replace it with. It says DAR PLUS on the side and the top says: HK66H-109 TTH1200-116 Built in Thermal Fuse 9623. Any help would be appreciated.
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