Why are headphone cables shielded?

jaencer · 3rd February 2010, 09:14 PM

I don't see the reason why pretty much ALL commercial headphones come with shielded wires (even the economy HPs). I mean, how much EMI or RFI noise would actually be audible? If you took an unshielded headphone cable and put it right next to a transformer, it still probably would move the diaphram enough to be audible...
Speaker cables aren't normall shielded, and headphones are little speakers...
So why are headphone cables shielded? Is it to reduce noise injected back into the circuit (and why would that be a problem? what would that do?)

Thanks for your knowlege

Iain McNeill · 4th February 2010, 12:02 AM

My guess is because shielded 2 conductor cable terminated on a stereo 3.5mm plug is mass produced in China for pennies. The shield does nothing as you say because of the low impedance of the amplifier and transducers.

It may also offer some strength to prevent the thin wires from breaking, but my money is on the cost factor.

Jen-B · 6th February 2010, 03:00 AM

Iain you are right that it's cheap in quantity, but it would be even cheaper if it was not there. I think the actual answer is that it's a combination of additional strength and crush protection.

mjf · 6th February 2010, 07:19 AM

hello.
i have a headphone connected to my computer soundcard.
with the shielded lengthening cable all is quiet,but with the unshielded cable i can hear a little (modem)noise in the background..........
greets

qusp · 7th March 2010, 05:18 PM

headphone cables are inherently low power/high sensitivity devices, which are much more susceptible to noise than wires carrying high current. a few microvolts of noise coupled into a headphone cable has a MUCH larger effect on the drivers as a result. that being said I only ever use shielding on home headphone cables (single ended) as they are generally much longer and tend to pass by more sources of interference than the occasional mobile phone tower like with portable. the home is literally full of noise these days with wireless LANs etc.

hope that answers your question

3rd February 2010, 09:14 PM	#1
jaencer diyAudio Member Join Date: Jul 2008	Why are headphone cables shielded? I don't see the reason why pretty much ALL commercial headphones come with shielded wires (even the economy HPs). I mean, how much EMI or RFI noise would actually be audible? If you took an unshielded headphone cable and put it right next to a transformer, it still probably would move the diaphram enough to be audible... Speaker cables aren't normall shielded, and headphones are little speakers... So why are headphone cables shielded? Is it to reduce noise injected back into the circuit (and why would that be a problem? what would that do?) Thanks for your knowlege

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Shielded cables - success	Brit01	Tubes / Valves	10	10th August 2009 04:08 PM
active shielded speaker cables	sunrise	Solid State	44	11th April 2007 06:28 AM
shielded cables in enclosure	MBK	Solid State	25	16th March 2004 03:31 AM
Shielded cables?	Dxvideo	Chip Amps	6	22nd January 2004 06:54 AM
Wiring headphone cables.	haffe	Headphone Systems	4	20th February 2003 12:58 PM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

4th February 2010, 12:02 AM	#2
Iain McNeill diyAudio Moderator Emeritus Join Date: Oct 2007 Location: Santa Cruz, California	My guess is because shielded 2 conductor cable terminated on a stereo 3.5mm plug is mass produced in China for pennies. The shield does nothing as you say because of the low impedance of the amplifier and transducers. It may also offer some strength to prevent the thin wires from breaking, but my money is on the cost factor.

6th February 2010, 03:00 AM	#3
Jen-B diyAudio Member Join Date: Jan 2010 Location: UK	Iain you are right that it's cheap in quantity, but it would be even cheaper if it was not there. I think the actual answer is that it's a combination of additional strength and crush protection.

6th February 2010, 07:19 AM	#4
mjf diyAudio Member Join Date: Jan 2009 Location: upper austria/near linz	hello. i have a headphone connected to my computer soundcard. with the shielded lengthening cable all is quiet,but with the unshielded cable i can hear a little (modem)noise in the background.......... greets

7th March 2010, 05:18 PM	#5
qusp is choosing a less facetious title... diyAudio Member Join Date: Oct 2009 Location: Brisbane, Australia	headphone cables are inherently low power/high sensitivity devices, which are much more susceptible to noise than wires carrying high current. a few microvolts of noise coupled into a headphone cable has a MUCH larger effect on the drivers as a result. that being said I only ever use shielding on home headphone cables (single ended) as they are generally much longer and tend to pass by more sources of interference than the occasional mobile phone tower like with portable. the home is literally full of noise these days with wireless LANs etc. hope that answers your question