Hum buzz or falut wire in my piano???

Okay I asked this before but now I got another problem.
 
I've been experience a hum or loud buzz from my piano for couple years.
I don't have to turn the piano up just leaving it at 0 I can hear the hum or buzz from the built in speakers.
 
I thought this might be a ground loop problem but I tried few gear and nothing else is effected.
And I tried to unplug EVERYTHING in my room but the piano and still it hums or buzzs.
 
So if non my other gear have this problem could there be a fault wire inside the piano?
 
Thanks

yes and yes

I'm going to guess that the hum is being caused by the proximity of the keyboard to another device (maybe a display monitor?) that is spitting out EMI or RFI. My guess is based on the assumption that this particular keyboard may not be shielded very well. The idea that the hum can be observed on the built in speakers with the level turned to "0" suggests to me that the noise enters the amplifier stage after the level control. It could be an internal issue like a wire with a degraded connection to ground or maybe a shorted blocking capacitor but I'm going to go with ineffective shielding and proximity to a noise source as my guess.
 
:-)

Thanks for all the responses and I agree must be the piano it self.
Right now I got it plug into strip by itself with piano lamp.
But still makes the hum buzz sound as well my friend/teacher said must be the piano.
 
I'm looking for new piano I don't have lot to spend but need some than good for classical
Mostly nice sound and good key touch I found few between Casio and Yamaha.
 
Yamaha p 150
http://www.amazon.com/gp/product/B008FVBX7A/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=ATVPDKIKX0DER
Yamaha np 31
http://www.amazon.com/Yamaha-Piaggero-NP31-Lightweight-Portable/dp/B005BRRO6U/ref=sr_1_2?s=musical-instruments&ie=UTF8&qid=1396941786&sr=1-2&keywords=yamaha+np
 
Casio priva px 150
http://www.amazon.com/Casio-PX150-BK-Sensitive-Tri-Sensor/dp/B0094KNESM/ref=sr_1_1?s=musical-instruments&ie=UTF8&qid=1396941847&sr=1-1&keywords=casio+priva
 
Thanks

It would be a fair test to take it to another room and plug it in by itself.

I second that. And, if it is using an external power supply, see if you have another one (check voltage and polarity).
 
Wilko

Dimmer in the wall right next to the home digital piano?
 
Compact fluorescent light in piano lamp?
 
Computer display monitor sitting on top of home digital piano?

At no point have you told us what this piano is? 
Does it have a wall wart or a direct AC plug. 
Also you were not clear about if there is a hum with headphones or audio output or both or if it's a Yamaha it only will have headphone out. so? 

Thanks for answering marcus.
 
Just to be clear I want to ask again.
 
Q: Compact fluorescent light in piano lamp?
A: Yes but the piano been doing this sense i've got 
 
Is there a compact fluorescent lamp nearby? If so unplug the fixture and see if it helps a little. Even if it only helps a little it will suggest what the problem may be.
 
 
It seems like you have done all the trouble shooting you can. It's possible a technician could trace down a specific problem and fix it... I doubt it will be an efficient or inexpensive process. If it were me I might trace the power supply looking for ineffective AC coupling leaving AC on the DC rails. It may be faster to simply start replacing filter caps, which is what a lot of techs do to save time. Even so, it's not really an efficient process, it's more like a brute force attempt to make a problem go away. It might help.
 
It can be, as you suggest a bad wire or solder connection... that's a search and repair process that is even less efficient. I think that factory wiring is a lot more consistent these days then back when the "bad solder" connection earned its reputation as a likely candidate.
 
Finally, I'd want to consider how loud the hum is. If you are paying attention you'll find low level noise in all sorts of consumer grade gear. If the piano sound is substantially louder than the hum, and effectively drowns it out for all but recording purposes, then it may just be inherent to the design and quality level of that product. Only you, and people who can listen to it first hand, can make that assessment.
 
Good luck!
 
best regards,
mike
 

Yeah fluorescent lights and dimmers can certainly generate stray electrical signals that will be picked up by amplifiers. I was under the impression (maybe false) that this had all been eliminated as a potential problem. You could simply turn off all the lights and run a three prong extension cord from another wall outlet that comes from another breaker. If you still have the noise then that pretty much isolates it, unless there are grounding issues concerning the entire house.
 
I have only used the Privia 150. I use it to track 88 key piano parts. I was having some issues with the sustain pedal tracking. There seemed to be a delay from when I pushed the pedal to when the midi was recorded. I haven't used it since I replaced the pedal with a better one..it might have been a problem with the pedal.