I purchased these today at a local retailer. Being a bit of a fanboy, I decided I wanted these even though I already own the QC25. I have only been listening to them for less than an hour, but I am very impressed. The soundstage is the thing that keeps wowing me. The separation and placement of instruments is really good. The comfort is supreme and the bluetooth paired very easily to my iPhone 6 plus. The QC35 arrived with 70% power out of the box. After almost an hour, they are still at 68%.

Sound impressions:

I always start with Thievery Corporation - A warning (Dub) from Sounds from the Thievery Hi-Fi album. This is about the deepest bass of any track I own. The QC35 handled it easily. Very deep and without driver rattle and still able to reproduce the midrange and treble. The rhythms in this song like to oscillate back and forth and that staccato effect is reproduced very well.
Next up was Steely Dan - Everything Must go. I started with Green Book as it has a very prominent piano (always the most difficult instrument to reproduce) and a "Lead Drum" pushing the song forward. This song also has a wide soundstage and, again, wow. I moved on to the Title track 'Everything Must Go." The song open with a cacophony of instruments all improvising with a rolling drum adding backbeat. On the QC25, every instrument can be picked out. The sax is wonderful and seductive.
Moving on, I played The Toadies "Possum Kingdom" to see if the grungy rhythm guitar could be reproduced. Sorry, but I got lost in this song and forgot I was reviewing. That is always the mark of a great headphone to me.
When I regained my senses, I played Sublime "Garden Grove" to see if the impact from the steel drum would show up. It did, easily.
Moving on, The Stone Roses "Love Spreads" was up next. Lots of chances to muddy up on this one - bass and lead play together with a heavy drum set. Nope, the QC35 handled and kept everything in it's place.

Oh, the noise cancellation. Come on...Bose owns here. Literally, they take legal action against any company that attempts to infringe on their noise cancelling algorithm. Even Bose detractors admit that they own the NC segment.

Should you buy the QC35? If you own no other NC headphones, it's a no-brainer. Get these today. If you want to cut the cord and have the best noise cancelling money can buy, get these today. If you are completely insane (like me), and already own the QC25 - well, your call on that one. You could probably purchase a bTunes add on for a lot less.

If you find this review helpful, go ahead and click on the button to let me know. If you have questions, leave a comment and I'll try to get to it quickly.

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Updated Tip: If you want to pair to more than one device, it's not real clear how to do that. This is what I found out playing around today. Power the QC35 on - you will hear it pair or attempt to pair with the last device. Now slide the power button to the on position again and hold it for 1-2 seconds and the voice prompt will say "ready to pair a new device."

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Tip #2: I have read a few reviews that wish Bose would have included a cable with controls instead of just a straight audio cable. I just checked and the QC25 cable Bose Quiet Comfort 25 Headphones Inline Mic/Remote Cable for Apple devices - Black works with all functions. So, if you really want that function, it is available.

Intro: If you want to experience what it’s like to go deaf and only be able to hear beautifully presented music, the QC35s are for you! With unbeatable noise cancellation, superb comfort, exceptional sound quality, and solid build quality, $350 may seem like a hefty price but it is worth every penny.

Design: The QC35 have practically the same design as the QC25, but with wireless controls built-in to the back of the right earcup. They feel tough and premium. The QC35 utilize Bose’s special plastic that is glass-filled nylon, soft Alcantara on the headband, memory foam in the earcup padding, slanted drivers inside for better comfort and soundstage, metal caps on the earcups, and solid clicky buttons. The mechanism for size adjustment is solid, and the QC35s can fit a wide variety of head sizes. The ear cups rotate 90 degrees, but the earcups face outward instead of inward when worn around the neck. The folding mechanism allows the QC35 to fit in the included carrying case (which is equally high quality in its build). Throughout the past two weeks of my testing, I have accidentally dropped the QC35 one or two times from around 4 feet, and they have suffered no damage whatsoever. Solid.

Comfort: In general, the QC35 headphones are very comfortable. Out of all my friends who tried it, the only one who complained about comfort has a relatively small head. This was my first time extensively using over-ear headphones, but I have no problem wearing them for several hours in a row. Comfort only improved over time, as the headband grew slightly looser through use. Due to the previously mentioned material choices and very reasonable clamping force, wearing these feels like having a pair of pillows hug your ears. Bonus: they can also sort of function as earmuffs during colder winter seasons – they're saved my ears from freezing numb, multiple times.

Noise Cancellation: There’s really not much to say. The Bose QC35 is simply the best noise cancelling headphone in the world. Previous iterations of Bose's noise cancelling headphones and earbuds convinced me that they had perfected noise cancellation and it couldn't possibly get better, but I was wrong. The QC35 isn’t massively improved, but it is even more perfect than previous Bose noise cancelling headphones. Noise cancellation feels extremely natural because it lacks the feeling of “pressure” on your ears when being used. The QC35 cancels sound so naturally and smoothly that it feels more very comfortable pair of earmuffs than electronic noise cancelling headphones. Previously, sudden noises (such as a shutting car door) would cause the QC20 earbuds to “pop”, when it fails to cancel the sound. The QC35 handles these situations much better. Bose was already the king of noise cancelling and these just takes that a step higher.

Sound Quality: Overall, the sound is warm, full, and relaxing, but fairly neutral in general. They’re not quite flat enough for monitoring, but all frequencies are very well represented. Whether listening to music or watching movies, everything just sounds right. Vocals, instruments, bass notes, bass rumbles, high-frequency sparkles all isolate from each other very well. Lower frequencies are impressive with a tasteful amount of bass: it’s exciting, but not overpowering whatsoever, and bass easily extends to below 20hz with no distortion! For the first time in Bose’s series of noise cancelling headphones, they sound almost equally as good turned off (and through a cable connection), as when they are turned on. Sound quality over Bluetooth is fantastic. Even the soundstage is quite respectable for a pair of closed-back, noise cancelling headphones. My only two wishes for the sound are: a) while bass is plentiful and consistent, the bass could use some more tightness and punchiness, and b) a little extra resolution would be nice

Features: First off, I would like to make it clear that Bose’s claims that the QC35 has 20 hours of battery life and 33 feet of Bluetooth range are utterly false - BUT in a good way! In my testing, the QC35 lasted me upward of 25 hours on a full charge, and after the battery was drained, they charged up very quickly. Even more shockingly, my testing reveals that the QC35 has more than DOUBLE Bose’s estimated Bluetooth range. When connected to my OnePlus One smartphone via Bluetooth, the range is at least 75 feet with no obstacles. With this insane wireless range, I have once left my phone upstairs in my bedroom, walked downstairs to grab a cup of water, and walk back upstairs with almost no stuttering. Honestly I have no clue how Bose pulled this off but it’s incredible being free from a physical connection. Additionally, I was extremely pleased to find that the QC35's volume and play/pause controls work on Android, iOS, and Mac OS X!! Edit: after testing the QC35 on more Android devices, I found that on some devices the headphone volume controls will adjust the phone's media volume, and on other devices it adjusts its own internal volume.

Comparison to the competition: When the Sony MDR-1000x was released, they were touted around the internet as the Bose QC35 killers, but having tested a pair, I can confidently say the QuietComfort 35 is better at making the world go "quiet", and better at being "comfortable". The MDR-1000x has a very audible electronic hiss with active noise cancellation enabled, and is not as good at ambient noise reduction or reducing the sound of voices, compared to the QC35. The QC35 is also significantly lighter with a much softer and well-distributed clamping force around the ears. In comparison, the Sony's felt hard on my head. In terms of sound, both are good in their own ways: the QC35 is smoother while the MDR-1000x is more aggressive, so take your pick on that.

Quotes: Here are a few testimonials from my friends who tried them out. Friend A: “Spending $350 on headphones is a LOT for me, but I hate to admit that I’d be very willing to pay for these, because they’re SO GOOD.” Friend B: “(to another friend) Dude you gotta try these, it’s like being put in another universe.” Friend C didn’t say anything. He just closed his eyes and started dancing in his seat.

Conclusion: I guarantee you that the Bose QC35 will make you smile, and you will love them, regardless of who you are and what you do. So if you have enough money to spend on high-end headphones, hesitate no longer and make yourself a very lucky person by owning a pair of QC35s.

Product seemed to be good, tech support is terrible!

I purchased this headphone and had been enjoying it since December 2016. I've found the sound quality and noise canceling features to be great until it started malfunctioning.

First, it started as some static in the left earcup. After an hour the sound started breaking, and now it does not work anymore. Tried to contact the tech support, which took about two days to get the first answer. Despite the fact I have filled the ticket with all details about the headphone (model serial) and my personal information (address, name, phone number), the person asked again for the very same information.

Another two days waiting and finally received a response with a few steps asking to test the headphone on other devices. Have tested it, sent the message with the same problem, and it has been radio silence ever since.

It's amazing to see the reviews here at Amazon with people complaining about defects and detailing their poor experiences with the tech support. Bose, this is not a cheap product and we expect an appropriate support for it. You cannot send a reply to these reviews asking to send an email to tech support after customers had already done it, to be just ignored or to get delayed and improper responses.

It does not matter the product is good if you don't act properly in a problematic situation.