How to get rid of monitoring speakers' humming?

[Guerrilla Tech]

one workaround is to make sure you are using balanced cables and monitors (or power amp if using unpowered speakers). This means xlr connections, or tip/ring/sleeve 1/4" plugs.

Experiment with ground lifters. Unplug or turn off everything else in the room or on the same circuit. Cheap dimmers, neon, or flourescent light are common culprits. Most common troublemakers I've found are dimmable halogen lights. I had one client who was affected by the dimmer on a torrchiere halogen in the next apartment. We found it when his neghbor turned on the light when I happened to be listening to the speakers and looking out the window.

[Jack Dawson]

OK...

The TRS connectors have 3 conductors, one being the shield.
On the speaker end only of each cable, disconnect the shield only by whatever means available. (cut, un-solder, etc.).

Jack

[Guerrilla Tech]

If its in your headphone jack too, the problem is not your monitor cabling.

Look for dimmers
make sure your power is three-prong, i.e. grounded
experment with ground lifters
check your AC power with a voltmeter, it should be around 117volts. More than 10v either way can be a problem. I had a problem at one studio when a regulator on the power pole shorted, and we were getting 130v. Caused some equipment to hum, and we went through light bulbs like crazy. This was after the last el Niño.

Also, make sure your whole system is plugged into the same circuit.

[hkju2]

The hum is not in the headphone jack.

Sorry for being not very knowledgeable, but I don't exactly understand how to disconnect the shield. Can you kindly advise me?? Thanks a MILLION.....!!

[Guerrilla Tech]

the shield is the wire that is not insulated separately from the other wires in the cable. It connects the ground between the two boxes. If it is not a molded connector, you can open up the 1/4" plug and desolder or cut it off of the plug. It is probably connected to the same tab that clips on to the whole cable for strain relief. Then take some electrical tape and isolate the spare wire so that it doesn't touch the plug.

Desoldering is preferable, as it is easier to replace if it doesn't work or if it gets worse. There is also the potential problem that is your speakers don't have a balanced input, the cable might not work at all without a ground.

I've found the only way to get rid of hum from Alesis Power amps is to use isolation transformers. Shure make some for abut $50 each.

[hkju2]

Thank you so much!!

[Icabod]

You said that the issue only seems to appear when you have the firewire cable hooked up to your Powerbook, correct? First make try plugging in the firewire cable to the 002R, but nothing else. Humming? If so, you may have a problem with either the cable (you said you changed that though), or the FW jack on the 002R. Try the other jack. If no humming, try connecting the Powerbook via FW. Don't turn it on. Hum there? If not, make sure the Powerbook's powerbrick is not connected, and try running the Powerbook on battery power. Try plugging in the powerbrick to the same circut as the 002R. Humming now? If so, do you have an external firewire drive? If so, plug that into the other end of the firewire cable, but don't turn it on or even plug it in to AC. Humming? If not, try plugging it into AC, make sure it is the same circut as the 002R.
Just simple trouble shooting. Get the system to a point where it doesn't buzz/hum then start adding things one piece at a time until it hums. When it does, you may have probably found the problem. Also, wiggle the cables a little. If it gets worse or better, you have a problem at that point.

[Fingaz]

I've got a pair of Mackie hr824 & a KRK V8 pair and 2 lcd monitors....a samsung and a norton micro...the speaker that sits next to the norton micro always hums - when it's the mackie it's really loud; the krk not as loud but annoying...as soon as I turn off the monitor the hum goes away.

[megahurt]

As soon as I connect a firewire drive I get noise in my monitors. I have tried 5 fw cables, all do the same thing.

Is there any way to stop this?

[alance]

Do you hear your fw drive ramp up? If so, your power has a poor ground.