OK, so I got a lot of qualified answers about wireless headphones and I have
decided to drop it!
BUT... I've just seen a pair Infrared wireless headphones!!: Sennheiser IS
380.
The guy in the shop told me that they sound much better than "normal"
wireless phones. No interferrence and no static noise...
Does anyone here know if that's true and what is your opinion on them, if
you have any...

Regards,
Leo

Leo wrote:

OK, so I got a lot of qualified answers about wireless headphones and I have
decided to drop it!
BUT... I've just seen a pair Infrared wireless headphones!!: Sennheiser IS
380.
The guy in the shop told me that they sound much better than "normal"
wireless phones. No interferrence and no static noise...
Does anyone here know if that's true and what is your opinion on them, if
you have any...

Infrared certainly won't suffer from interference from the 'usual' RF sources.
The trouble is that former IR phones have suffered from different technical
limitations - do you have a link ?

Graham

Leo wrote:

OK, so I got a lot of qualified answers about wireless headphones and I
have decided to drop it!
BUT... I've just seen a pair Infrared wireless headphones!!: Sennheiser IS
380.
The guy in the shop told me that they sound much better than "normal"
wireless phones. No interferrence and no static noise...
Does anyone here know if that's true and what is your opinion on them, if
you have any...

This was about 8 years ago and they were consumer headphones, but the ones
I used to have (made by Philips IIRC) did exhibit some interesting
interference problems if used at night in the vicinity of energy-saving
lightbulbs or fluorescent tubes. They also have to be line-of-sight with
the transmitter, but that goes without saying.
I guess the susceptibility to interference and the way it manifests
will depend on the type of signal modulation used. Don't know if there's
enough bandwidth in an IR link to do uncompressed digital transmission.


Regards,
Leo

--
JP Morris - aka DOUG the Eagle (Dragon) -=UDIC=-
Anti-walkthroughs for Deus Ex, Thief and Ultima http://www.it-he.org
Reign of the Just - An Ultima clone http://rotj.it-he.org
The DMFA radio series project http://dmfa.it-he.org
d+++ e+ N+ T++ Om U1234!56!7'!S'!8!9!KAW u++ uC+++ uF+++ uG---- uLB----
uA--- nC+ nR---- nH+++ nP++ nI nPT nS nT wM- wC- y a(YEAR - 1976)

Leo wrote:
OK, so I got a lot of qualified answers about wireless headphones and I have
decided to drop it!
BUT... I've just seen a pair Infrared wireless headphones!!: Sennheiser IS
380.
The guy in the shop told me that they sound much better than "normal"
wireless phones. No interferrence and no static noise...
Does anyone here know if that's true and what is your opinion on them, if
you have any...

Regards,
Leo

There can be a problem with 120 Hz interfernce from fluorescent
lighting. IR headphones operate at a much higher modulation frequency
but I have experienced a problem when this type of lighting is really
bright. Sennheiser may well have eliminated such interference but it is
something that you might want to check.

Pooh Bear schrieb:

Leo wrote:

OK, so I got a lot of qualified answers about wireless headphones and I have
decided to drop it!
BUT... I've just seen a pair Infrared wireless headphones!!: Sennheiser IS
380.
The guy in the shop told me that they sound much better than "normal"
wireless phones. No interferrence and no static noise...
Does anyone here know if that's true and what is your opinion on them, if
you have any...

Infrared certainly won't suffer from interference from the 'usual' RF sources.
The trouble is that former IR phones have suffered from different technical
limitations - do you have a link ?

AFAIK first generation IR phones with carrier frequencies in the
100-300 kHz range suffered from interference caused by electronic
energy saving lamps.

Newer phones like IS 380 work with carrier frequencies of about
2.5 MHz.

http://www.sennheiser.com/sennheiser/icm.nsf/resources/IS380.pdf/$File/IS380.pdf

Nonetheless, there will be that limited S/N ratio well known from
FM systems. And, of course, the headphones must "see" the IR
transmitter ...

But there was Sennheiser's IS 850 digital infrared system which
provided sound quality comparable to that of wired headphones
though I doubt that it's still available ...

HTH

Reinhard