Audio-Technica ATH-A700's making a humming noise

[jimmyb]

I've just bought a pair of Audio-Technica ATH-A700 headphones for music/films/gaming etc and also for plugging into a bass amp for bass guitar.

I think they're really great headphones but I've got a quick question.

When plugged into my bass guitar amp and pc there's a slight buzzing in the background when I've got the headphones on but not playing music through them. When I play music at a comfortable volume I cant hear the buzzing but obviously at silent points in the music its audible.

I was just wondering if this is:

• A general occurrence and nothing to be worried about;
• A problem with my amp/pc or;
• If its a problem with the headphones?

[henders]

It sounds like you are picking up interference from somewhere. I'd check your cabling.

[ShaunG]

jimmyb: Glad to hear you like the headphones.

I would say that it's very unlikely to be caused by a problem with the headphones. If the headphone drivers were faulty you would expect crackling or distortion during the music, rather than in the quiet sections. The hum you are hearing is likely to be from the mains (50hz) or some other electromagnetic interference. This noise will be moving the drivers in the headphones in the same way as an audio signal.

The A700's are very sensitive headphones, so will highlight the smallest amounts of noise and hum in the signal.

It would be worth checking the signal path to ensure all the cables are well shielded. Low quality cabling without adequate shielding will be more prone to picking up interference from nearby electrical and electronic devices.

Computers are notorious for creating electromagnetic noise. As I'm sure you know taking an analogue signal directly from an internal PC or laptop soundcard is not an ideal solution for getting a good signal out of a PC. Some sound cards solve this by providing external boxes that convert the signal from digital to analogue. See some links below:

http://www.m-audio.com/index.php?do=...y&ID=recording
http://www.lexiconpro.com/ProductIndex.aspx?ProductID=7