Hi all, first post and a bit clueless when it comes to amp-talk.
I was, stupidly, having a party and had the volume loud on my Marantz PM4400 amp - black from 2003, not the recent, silver one.
Sound just cut and not picking up anything from any source.
Have tested speakers and inputs and all work on other systems, but the amp still doesn't work.
The power light comes on and no hum or anything - also, no sound whatsoever from amp when speakers and source plugged in.
Have only had this for 2 weeks.
Please, if anyone has any solutions - possibly a blown fuse or fuses? - I'd be very grateful.
Thanks
I was, stupidly, having a party and had the volume loud on my Marantz PM4400 amp - black from 2003, not the recent, silver one.
Sound just cut and not picking up anything from any source.
Have tested speakers and inputs and all work on other systems, but the amp still doesn't work.
The power light comes on and no hum or anything - also, no sound whatsoever from amp when speakers and source plugged in.
Have only had this for 2 weeks.
Please, if anyone has any solutions - possibly a blown fuse or fuses? - I'd be very grateful.
Thanks
Are there any relay clicks ? Blown transistors and DC Speaker Protection active perhaps. Measure DC on the outputs before the speaker relays, since if protection is engaged they are cutting the circuit. If you get more than a few millivolts the output stage is "kapputt"
Thanks for the reply.
No relay clicks.
How do I measure output?
Sorry, very clueless when it comes to speaker talk
No relay clicks.
How do I measure output?
Sorry, very clueless when it comes to speaker talk
Take the cover off, be careful with high voltage inside before mains transformer.
First check if there are blown fuses and replace them with the same rating.
If all goes well and they don't blow right away attach one speaker terminal and just touch with the wire at the other terminal looking for hum or dc (speaker cone stays in or out) or if you are lucky you'll get some sound.
With a multimeter in DC 50V range put black probe at the black speaker - terminal or power supply ground, put red probe at relay inputs (follow power transistor PCB tracks). Relay have usually 4 terminals, 2 for the coil and 2 for speaker input and output (Could also have more contacts for cutting ground or speaker - or just one relay for both channels). You could bypass the relay shorting its contacts, but don't connect the speakers unless you use a say 100 ohm 5w resistor in series. if you hear hum or distortion transistors are gone.
Can you post some pictures of inside or schematic ?
First check if there are blown fuses and replace them with the same rating.
If all goes well and they don't blow right away attach one speaker terminal and just touch with the wire at the other terminal looking for hum or dc (speaker cone stays in or out) or if you are lucky you'll get some sound.
With a multimeter in DC 50V range put black probe at the black speaker - terminal or power supply ground, put red probe at relay inputs (follow power transistor PCB tracks). Relay have usually 4 terminals, 2 for the coil and 2 for speaker input and output (Could also have more contacts for cutting ground or speaker - or just one relay for both channels). You could bypass the relay shorting its contacts, but don't connect the speakers unless you use a say 100 ohm 5w resistor in series. if you hear hum or distortion transistors are gone.
Can you post some pictures of inside or schematic ?
Thanks MAACO, will get on this tomorrow and post pictures of inside. And definitely disconnect from mains before attempting to change fuses.
Really appreciate the help and hopefully will get it sorted.
Will keep you informed...
Really appreciate the help and hopefully will get it sorted.
Will keep you informed...
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