
The high power infrared transmitter incorporates multiple light-emitting diodes (LEDs) for an extended coverage range. The MDR-IF540RKs have a transmission range of twenty-four feet (ten feet when at a forty-five degree angle.) They also receive at a ninety degree transmission angle, ensuring that you have uninterrupted listening as you move around the room. The headband is self-adjusting and sports a snug-fitting wide band. The headphones require one AA battery. If you use an optional alkaline battery, you can expect an impressive one hundred hours of use. If you choose to save batteries, simply use the included rechargeable battery and the supplied transmitter/recharger. Using this recharging system, you can expect thirty hours of use.
The headphones are lightweight and comfortable, delivering quality sound. Sony has installed several technical features to the headphones to ensure a quality listening experience. The thirty millimeter drive units deliver deep bass, low distortion and a wide frequency response range (12 - 24,000 Hz). Ferrite magnets give the headphones high energy at a minimal size and weight. The PET diaphragms offer low distortion and resists bending and flexing. The open-air design allows for ambient noise to enter the ear, a safe and observant feature.
With the supplied UniMatch plug, it is easy to connect the transmitter to various sound sources. These plugs accommodate both the phone jack found on high fidelity components or the mini-jack found on video components. A single volume control is found on the right earpiece for simple volume adjustments. Finally, there is a automatic power switch on both the headphones and transmitter to help conserve battery and equipment life. (The unit turns back on when the transmitter detects a signal, while the headphones turn on when they sense their placement on your head.) The headphones weigh 6.3 ounce and are a modern black color.
What's in the Box
Sony MDR-IF540RK headphones, high-powered transmitter/recharger, NiCad rechargeable AA battery, connecting cable, UniMatch plug adaptor, AC power adapter and user's manual.

Works great, most of the time...
This is my first set of wireless headphones. I bought them so my kids can watch TV in the living room at night without bothering me in the next room. I am using them with an ONKYO receiver, Satellite, PS3, and HD tv set up. I have the headphones tied into the receiver.
First time I tried them, there was a noticeable amount of static. The second time, however there was none. What changed? The time of day. The manual says that direct sunlight can interfere with the signal, and sure enough it does. My AV rack is near a window that gets a lot of sun during the morning (the first time I tried them), later in the afternoon when the window was in the shade the static was gone.
I have a large living room that is adjacent to our kitchen. I get good reception within the full TV viewing range.
The headphones are comfortable, although they tend to make my ears sweat after a while. I like the recharge base, and the overall look of the headphones. I didn't like the short (about 3 feet) phone jack cable that the unit came supplied with. I had to rearrange my stereo components to allow the cord to reach the headphone jack. Also, don't like having to plug/unplug them when I go to use them, but other than these minor annoyances, they sound great and get the job done.

Cordless Headphones, Sony MDR-IF540
I bought these headphones for my 83 year old dad who wears hearing aids in both ears. He can't hear the new tv. The hook up was simple and they worked great right out of the box. The instructions were simple and easy to read. Sony gives you a couple of different ways to plug in, depending on what set-up you have. They play loud enough for him and they don't make the hearing aids buzz. I feel that they are outstanding for the money and Amazon always makes buying from them simple and once again, a very good value.

Good while they lasted
I've owned these headphones for almost 5 months now. A little over a month ago, the sound started cutting out in the right ear. I was able to play around with it and move the headphones around and it'd come back. Annoying, but at least I could get it working fairly easily. Unfortunately, those days seem to be over as that doesn't quite do the trick anymore. The warranty was only for 90 days and they now charge about to repair them (not to mention return shipping). I wouldn't recommend them unless you buy an extended warranty. Even then, they weren't exactly the greatest headphones in terms of sound. I'd recommend avoiding them.

Only get this if you don't like quality sound
Well, I had high hopes for this product. I should have known better. Basically, you get a lot of static no matter how you adjust the knobs. Nuff said. Always that background noise, no matter what. This will work if you are watching TV in bed and don't want to wake the wife, but forget any sense of realism if you want immersive sound in a gamer environment or quality live music. I returned my set after about 40 minutes out of the box. Plus, you have to really aim the IR transmitter perfectly just to get a decent signal, and it cuts out any time you move around or place your hand in front of your face. Much better to suffer the wire than to purchase this. Don't do it.

Sony headphones
I really like the headphones. When they go out of range the sound just cuts out. My other headphones produced loud fuzzy static when they went out of range. The surround sound is interesting, but I could leave it also. The vibration affect doesn't do that much for me, but you can turn it off if you want, which is nice. They fit nice and are light. The sound is first class. I would buy them again.

Volume control is provided in one earpiece that adjusts volume for both channels, ferrite magnets ensure the ample production of sound, and a self-adjusting headband automatically adjusts to your head's shape for maximum comfort. The system automatically turns on when you put it on your head, so there are no cumbersome switches or buttons to flip on.

Not for Plasma TVs
Not a bad set for the price, but they should put in bold letters "NOT FOR PLASMA TVs". The infra-red "noise" from the Plasma TV screen interferes with the IR signal to the headphones, creating a buzz. No way around it.

Song headphones
This is our second set we have bought.
The headphones are worth the price. The sound is decent but they do have drawbacks.
You have to almost be in front of the TV if using them for this purpose.
Also, after a short time the ear pieces can make your ears hurt. The cup has only a thin piece of foam. Maybe with a thicker foam it wouldn't be so bad.
On the whole for what we use them for, the're fine.
Sony product lover.

Sony wireless headphones
A very good product! Sound is very clear and the product was very easy to install. The headphones are very lightweight and comfortable to wear. The only problem is the small range of distance. All in all though, a good product for the money!

Great Headphone but.....
The Sony MDR-IF24ORK wirless headphone has great sound quality and I like the rechargable headset battery, however the head cross bar gets a little hard on the scap after a few minutes of use. It needs padding!!!!

Sony makes good stuff.
I bought these earphones for my wife who is hard of hearing. I did not tell her I was purchasing them and when they came she said she did not need them. I coaxed her into trying them and now she wears them all the time. The recharger/stand is a great feature and the fact that you do not have to turn them on or off between each use makes them very easy to use. We are 100% satisfied.