Hum Removal

I am using either a Sennheiser headset that plugs in using the pink and green plugs to the soundcard or a Raptor HD40 headset which connects via a USB 2.0 port. In either case I get a low frequency hum when I record to Audacity and I get this on a Lenovo X300 laptop running Windows 7 and Audacity 2.0.2, another Alienware 17 laptop running Windows 8.1 and a desk PC running Windows 7 both with the same version of Audacity. The two laptops are in the garage and the desk PC s in the house. The mains power to the garage comes from the house.

I have attached a small sample file of a recording of the hum and if there is anyway to get rid of it I would be grateful to hear how to do it/what’s causing it.

Didn’t know that gaming headset from Corsair, so I turned to auntie google…

This is the first hit:

Maybe it’s like your problem?

My Corsair headset is a USB connected device and as I said in my post, I get exactly the same outcome when using the Sennheiser headset which connects via the microphone/headphone sockets (the pink and green connectors) so I don’t think it’s relevant, sorry.

It is like walking into a blind alley, isn’t it?

Can you run one of the laptops on batteries and try it again? Still on batteries try it out in the street or meadow.

I have a Giant Hummy Monster that lived in the attic. He makes recording in one of the bedrooms impossible because of excessive hum pickup—even on batteries. All equipment works famously outside of that room. It may also have to do with the high tension wires that go over the house (attached).

Traditionally it’s difficult to filter that sound in post production because it involves a number of frequencies. Hum isn’t one thing.

It’s possible you have wiring errors in your house. I’ve had several in mine. You can buy a wall power tester. This is what the US one looks like. It can test for reversed wires and “Hot” where “Neutral” should be.

Outlet Tester (GRT-3500) at Aubuchon Hardware

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Have you read the solution?

If that is the solution, the outcome could be the same with the Sennheiser…

You either have a hardware ground loop, which is possible, of course, or you have a slight hum, which is amplified by the Windows setting.

But a hardware ground loop seems somewhat less plausible, since the hum is present on three different computers, with two kinds of interfaces.

But then, like The Koz said, It is like walking into a blind alley, isn’t it?

I was hoping that someone could analyse the hum recording and tell how it was being generated,

You live in a 50 Hz country and it’s being generated the the local power company.
Did you try the batteries?


Oh, OK, I hadn’t picked up on that. I’ll give it a go on both the laptops running on batteries. Thanks for pointing it out again. Sorry I didn’t pick it up first time you mentioned it.