[patrickt888]

Just picked up some used gears & started to put together a 2 channel system: Bryston 4BSST, Classe CP-500, Benchmark DAC1 & a Pioneer DVD with B&W 802N.

I was getting a small buzz on the speakers and was told this could be a ground loop problem.

Got some advice from a few people and some google & forum search etc... I tried the following

- Amp by it self ... no buzz
- Amp with pre-amp (unbalance interconnect, tried many different cables) ... buzz
- try removing ground from power bar, connect preamp to powerbar ... buzz
- try preamp & amp plug into this 'no ground' powerbar ... buzz
- Amp with pre-amp, but remove either left or right interconnect ... no buzz
- try DAC (DAC has variable out) to AMP ... no buzz

Did not know what else to do, so I connect all the components back together, and started to listen to some music. I figure I'll live with the buzz.

When I stop the CD, I notice there is NO buzzing sound. At the time the furnace was running. I waited until the furnace stop, and the notice buzzing is back.

I tried turning the furnace fan on & off, it did affect the buzzing.

furnace fan on - no buzz
and fan off - buzz.

Amp is on a a dedicated 15 Amp circuit, while the rest of the components are on another 15 Amp circuit.

Any ideas for what I should try next would be greatly appreciated.

Thanks
Patrick

[werd]

Just picked up some used gears & started to put together a 2 channel system: Bryston 4BSST, Classe CP-500, Benchmark DAC1 & a Pioneer DVD with B&W 802N.

I was getting a small buzz on the speakers and was told this could be a ground loop problem.

Got some advice from a few people and some google & forum search etc... I tried the following

- Amp by it self ... no buzz
- Amp with pre-amp (unbalance interconnect, tried many different cables) ... buzz
- try removing ground from power bar, connect preamp to powerbar ... buzz
- try preamp & amp plug into this 'no ground' powerbar ... buzz
- Amp with pre-amp, but remove either left or right interconnect ... no buzz
- try DAC (DAC has variable out) to AMP ... no buzz

Did not know what else to do, so I connect all the components back together, and started to listen to some music. I figure I'll live with the buzz.

When I stop the CD, I notice there is NO buzzing sound. At the time the furnace was running. I waited until the furnace stop, and the notice buzzing is back.

I tried turning the furnace fan on & off, it did affect the buzzing.

furnace fan on - no buzz
and fan off - buzz.

Amp is on a a dedicated 15 Amp circuit, while the rest of the components are on another 15 Amp circuit.

Any ideas for what I should try next would be greatly appreciated.

Thanks
Patrick

learn to like the buzz....  . jk . Does the buzz get louder as you turn up the volume. If so its in your volume ctrl of your preamp. Buzzes also mean lose wires somewhere. This is all trial and error stuff

[patrickt888]

Forgot to mention that the buzz is same regardless of volume.

Patrick

[werd]

k get a screwdriver and open up the outlet and make sure everything is tight on both hot and neutral.

[mackortoyota]

Are your power amp and other stuff on the same phase?

[werd]

 Get rid of the power bar. Plug everything into the wall. Your power bar is conflicting and probably even shot. You shouldn't be using a power bar with bryston anyways.

[patrickt888]

All components are plug direct to the walls, and I used the device from homedepot to check the socket & it is correct.

Already tried plugging both the pre-amp and amp with nothing else connected into the same wall socket. But no luck. Will check the wall sockets to see if all connections are tight as suggested, Thanks.

The only funny thing is that when the furnace fan is running, the buzz goes away. The furnace is about 20 feet away in a separate room.

How is the furnace fan affecting this ?

Patrick

[mjosef]

Are both of your dedicated lines on the same panel pole/rail? If they are not, one of the circuits may be picking up some noise. Determine whether they are on the same pole/rail and that its opposite to the one that your furnace fan are on.

[ricko01]

while its a pain in the butt (and I have been through this before).... uncable the whole lot and remove all the components from your rack except the pre-amp and the power amp. Connect pre/power to their own outlet and connect the interconnects between the two.

check for the buzz... if its there then connect both to the same outlet (direct into two port outlet or via a bar).

What can happen is that running both off different outlets can cause a ground loop.

Hopefully if the issue is between the pre/power then the above will solve it.

If you get the buzz still with the pre/power despite the different power connection strategies, check/swap power cables and interconnects with others you have.

Now if when you 1st connect pre/power you get no buzz, add in the other components one at a time and when you get it, check power cables/interconnects etc.

Also check its not component proximity (ie power transformers causing issues).

I did this and found:

1- that I needed to connect all components to one "bar" (in my case an Audience AR12)
2- I needed to move my BP26 power supply away from the rack

My floor noise went way down but it took my a long day to work it all out.

also while people tell you about needing multiple dedicated power outlets, buy a wattsup power montior and run your system off one power bar. Check what your peak uasge really is.

I have 4 monoblock power amps and aside from startup I never use more than 10amps. I am now a great believer in running all off one outlet... to eliminate completely ground loops due to floating earths.

Peter

[Wayner]

You have the cause. It's your furnace motor. It has a start capacitor and in the off condition is slowly draining. This is putting a low level hum component into the line circuits in your home. You can tighten screws and swap power strips all you want and it wont help. The noise is coming up thru the neutral.

Tripp-lite has a product that may help. We used these at work in our automated machine modules that kept noise and hash from all of the 120vac junk in the electrical cabinet. The thing is only $50. It may cure the noise problem http://www.parts-express.com/pe/showdetl.cfm?Partnumber=125-142. Tripp-lite also makes a power conditioner for about $100 that may work even better http://www.parts-express.com/pe/showdetl.cfm?Partnumber=125-100.

Wayner

[b5pt9]

Great info here

[satfrat]

Just thought I'd throw out this Jensen Iso-Max Isolator  @ Audiogon incase it's something that might help ya out with the hum issue. 
 
Cheers,
Robin