Defective Marantz PM6005 ?

[Taijitu]

Hello guys,

I'm a happy owner of a Marantz PM6005 amplifier. Recently, I started to hear some kind of "rumbling" coming from the body of the amplifier (not through the speakers). After some investigations, It appears the intensity of the noise is time-dependent : 90% of the time, it is almost not audible but sometimes it becomes a bit louder so that I can hardly hear it when I'm at about 2 meters of distance. I tried to disconnect all the wires, changed the plug and nothing changed.

Is it a feature of this amplifier or it is a bad news ?

Thanks !

 

[Covenanter]

Hello guys,

I'm a happy owner of a Marantz PM6005 amplifier. Recently, I started to hear some kind of rumbling coming from the body of the amplifier (not through the speakers). After some investigations, It appears the intensity of the noise is time-dependent : 90% of the time, it is almost not audible but sometimes it becomes a bit louder so that I can hardly hear it when I'm at about 2 meters of distance. I tried to disconnect all the wires, changed the plug and nothing changed.

Is it a feature of this amplifier or it is a bad news ?

Thanks !

"Rumbling" is an odd sound! The most likely candidate for noise from an amplifier is the transformer.

Chris

 

[Taijitu]

"Rumbling" is an odd sound! The most likely candidate for noise from an amplifier is the transformer.

Chris

Actually i'm not sure of the right term which describes what I hear. At the first sight, I would have say it's the noise coming from a fan. When it is "loud", it gives the impression to come from different sources, not only the transformer.

 

[Covenanter]

Electronic components don't make any noise, even faulty ones, so I still suspect the transformer. A bad transformer can vibrate and if that is transferred to the casing that could explain your symptoms. Anyway I would take it back to the dealer.

Chris

 

[Vladimir]

Most likely a combination of nasty DC in your mains and the transformer being loose. If the amp is under waranty take it back to have it sorted. You can tighten it down yourself but this way you can be sure its not something more serious, like the bias gone out of adjustment. Marantz has usually impecable customer service, there shouldn't be any headaches. Even if the amp is out of waranty, see if the dealer will do the checkup for free or for cheap.

As for the DC in your AC, that you can check for yourself with a DMM. If you aren't handy, get someone who is. Poking in the mains isn't a joking matter.

 

[Taijitu]

Thank you guys. A last precision : there is no noise when the amplifier is in standy mode.

Anyway, the amplifier is still under warranty. I will contact my dealer to see what can be done.