Buzzing noise.


Hi every one,
I have question about the buzzing noise from speakers .....!!!
As I just hooked up my system :
WILSON SHOPHIA 3 SPEAKES
PASS LABS X250.5 POWER AMP
MCINTOSH C50 PREAMP
OPPO 105D BLU-RAY/CD/APPLE TV
MIT SHOTGUN SPEAKERS CABLES "brand-new"
SHUNYATA STAIR/ANTARES XLR CONNECTION "brand-new"
SILNOTE POWER CABLE for all components "brand-new"
MONSTER AVS PRO 2000 power ..
I don't why when I turn on the power amp first then I hear the buzzing noise from speakers it was not loud but you can hear if your ears very closed next to speakers then I turn on the preamp next, the noise go away but you still can hear the buzzing just very little.!!!!.
Can you tell me what is that problem and what I have to do !!!!.
Or do I need more time to burn those cables ! Do I need to burn at least 50 hours ...then the sound will be improve and better as they are supposed to be right !
please let me know
thanks in advance
tanlv702
Start at the beginning. Are you using a dedicated AC line for your HiFi? Or do you share AC receptacles with other devices in your home?
If you have appliances or dimmer lights on the same line as your audio components, you are likely to hear hum due to a grounding problem.
You have a ground loop. Disconnect the Apple TV and test for the buzz. If that doesn't work pull the Monster Pro from the system and see if that does it.

As I just hooked up my system :

"Just hooked up my system"? Please explain. From previously having the same system hooked up? Did you have the same buzzing sound before? No? What did you change in the system?



I don’t why when I turn on the power amp first then I hear the buzzing noise from speakers it was not loud but you can hear if your ears very closed next to speakers then I turn on the preamp next, the noise go away but you still can hear the buzzing just very little.!!!!.

You should never turn on the power amp first. It should always be turned on last and should always be turned off first.


Power up sequence for audio equipment.

Front end equipment on first >>> then preamp >>> then power amp last.

.

Power down of equipment.

Power amp off first >>> then preamp >>> front end equipment last.


I don’t why when I turn on the power amp first then I hear the buzzing noise from speakers it was not loud but you can hear if your ears very closed next to speakers then I turn on the preamp next, the noise go away but you still can hear the buzzing just very little.!!!!.
A power amp should always be the last component to be turned on, and the first component to be turned off. It is not surprising that there is noise when the power amp is on but is connected to an unpowered preamp.

From your description it sounds like the noise level when everything is turned on is so slight that it might not be a problem at all, and might even be normal for the particular combination of components. But if not it could be caused by a lot of things. Including the possibilities the others have cited, as well as radiated interference between components or cables or the power conditioner simply resulting from them being too close together.

If you feel that the noise level that is present when everything is turned on is not normal, and if the power conditioner is located close to any of the other components, that is what I would focus on first. Either move the conditioner further away, or for experimental purposes try disconnecting it from the system and the AC altogether.

And if the power amp is located close to any of the other components, also try relocating it further away.

And regarding the possibility of a ground loop issue, for experimental purposes try temporarily putting a cheater plug (a 3-prong to 2-prong adapter, with the safety ground pin unconnected) on the AC plug of the preamp.

Let us know the results. Regards,
-- Al