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Question: What is the voltage of AC adapter? support 240V ?
Document: Unlike an older wireless analog pair I had, I can easily feel where the power and volume control is while wearing them. The volume control is great. The sound was too low when I tried to use an adapter and various analog headphones from my TV's optical audio, so thank goodness for these headphones.
We tried two previous sets of Sennheiser headphones, neither of which worked with our TV. Our TV has a digital input but would not work with the adapter that most headphones require (we tried two adapters). Most headphones require the adapter because their output is not digital. So...I searched for headphones with a digital output and found these. They work perfectly!!!!! So happy.
I really like the headphones. My only complaint is the charging station... or more so the actual power adapter. It lets off a very high pitched frequency when it's plugged in. I obviously don't notice it when I'm using the headphones, but when they are charging on the base station the noise drives me nuts. I unplug it when I'm at home and have to remember to plug it in when I leave the house so that they have a charge when I want to use them.
Excellent sound quality. I wanted 3 of these wired to TV but the single optical port on the TV could only support to be split once. I had to send one back at my expense plus a 15% restocking fee. The product is outstanding!
I wanted a wireless headset for my TV listening pleasure. The MDR-DS6500 provides excellent audio for both voice and music. I was getting an echo after a few days and called support. They had me relocate the cable from the back of the TV to the back of the  cable box. That did the trick, but I still don't know why no echo the first few days?
Sony's usual parts and labor warranty normally only covers 90 days and today is the 4 month anniversary of my purchase. To my delight, Sony warranties this product longer but you have to obtain an "event number" from Sony E-Support online, then package them up and send to Laredo Texas for replacement or exchange..most often with a refurbished pair.
I would not buy the Sony MDR-DS6500 again.I am sending mine back.I have had this equipment for two weeks.Main problems are echo and fuzzy sound.These problems were reported by several others.So it seems Sony would have a helpful answer, but no!Sony customer support said take it to aSony repair shop and get a cost estimate.No thanks.
I had been using some Bluedio R headphones for a few months to watch TV and movies and fell in love with them because they have 8 speakers which provides a very good surround sound experience. However, I recently upgraded to a larger TV that does not support bluetooth headphones, so I selected the Sony MDR-DS6500's mainly because of the optical input and rave reviews from satisfied owners, but I must say that I have been very underwhelmed by the Sony headphones.
They work OK, are comfortabe and sound good but there is too much delay. I had it plugged into the optical digital output from my Onkyo AV amp. I wanted to be able to listen at a different volume level than output from the sound system speakers. Unfortunately the delay caused a very noticable, annoying echo no matter what settings I tried. Even talked to Sony tech support to no avail. I returned them becuse they were not functional for my application.
These are the first I have found that actually work, after trying several others and trying to make my Sennheiser headphones work with digital/analog converters. My new Samsung UHDTV has "digital-out-only ports" and will not support analog headsets even with converters. I am satisfied with the headphones even though they are a bit heavy and bulky. Took me 3 months of trial and error to find workable headphones. Sony would not price match from their nearly $300.
Answer: Voltage is strictly 120 VAC / 60 hz only.