Bose QuietComfort 35 is a top-of-the-line active-noise canceling headphones with wireless connection from Bose. It packs everything we would expect from a pair of headphones with active noise-cancellation. From much-improved noise-cancelling technology, 20 hours battery life, optional wired-mode, super comfortable and lightweight design, carrying case, multi-point technology and superb sound quality, this is as good as we can get from Bose today, assuming that one is willing to pay its premium price tag.

Let’s start with design and build quality. These headphones feels lightweight and mobile enough to carry around. The included carrying case is a good quality hard-case. Not exactly the smallest form I would expect, but it’s probably the best we can get. QC 35 needs to be folded on one side to fit inside the case. The included airline adapter has its dedicated spot inside. The headphones material is comfortable. I am a bit worried that choosing the silver model would make it look dirty in no time, but I shall see about that.

Headphones controls are fairly straightforward. There is a switch on the right side to turn it on and to activate Bluetooth pairing. There are the usual 3 buttons: volume up, volume down and multi-function button to play/pause/answer. Thanks to multi-point technology, I can connect QuietComfort 35 to both my phone and computer at the same time, allowing me to do work and listening to music from phone.

When I started using my new QuietComfort 35, I immediately opened my Bose Connect app and it automatically upgraded the firmware into version 1.2.10. Later on I read that QC35 performance is largely affected by firmware version. Some people love its performance with firmware 1.0.6 and choose to stay with the old firmware. Some others choose to move on. We can easily change the firmware by going to http://btu.bose.com/ from a desktop computer (Windows or Mac) and download the Bose Updater app. Connect our headphones and when in the screen with available firmware versions, we can press the letters a, d and v in our keyboard, followed by pressing arrow up and arrow down. It will allow us to downgrade firmware after doing these steps.

Knowing that I could test both the famous 1.0.6 firmware and the latest 1.2.10, I decided to do so.

First I tested my Bose QuietComfort 35 using firmware 1.0.6. Noise cancellation is truly top of the class. The world becomes quiet. Then, music sounded amazing. All the highs and lows are very detailed. I had one of the most enjoyable sessions of critical listening in the last several years. I can quickly understand why QC 35 received such great reviews from a lot of users and I could understand why this firmware version is popular. This firmware, however, is not perfect. One, during 3 hours of music listening, I noted 5 occurrences of brief connection drops. It was quickly resumed after a second, but still noticeable and not the kind of experience we expect to have from a high-end product. Next, after 3 hours of listening, I feel that the active noise cancellation somehow gives a depressing impact to my head. Definitely not a comfortable feeling. I read some users reporting this and I was initially skeptical, until I experienced it myself. Last, of course the old firmware doesn’t have the new features such as music sharing.

I upgraded my headphones to firmware 1.2.10 and can confirm improvements in Bluetooth connection. It becomes a lot more stable. Not a single drop during another 3 hours of listening. The depressing impact from active noise cancellation is gone, but I also noticed that the noise cancellation is not as solid as the one provided by firmware 1.0.6. To be fair, the noise cancellation in 1.2.0 is not bad, and if I have never experienced 1.0.6, I probably wouldn’t know that a better noise cancellation exists. I guess it’s a trade-off between really solid noise blocking and the cost of depressing effect.

From almost every source I could read, people are saying that firmware 1.2.10 is a massive improvement from the disastrous 1.2.9. I couldn’t comment on that because I have never tested 1.2.9. However, I can write here that sound quality with firmware 1.2.10 has some noticeable differences from firmware 1.0.6. For starter, 1.2.10 loses some of the great details of sound I thoroughly enjoyed in 1.0.6. Again, the sound quality is not bad at all. It’s still a great sound quality, especially when not being directly compared. On the plus side, I also noticed that 1.2.10’s sound stage is slightly improving from 1.0.6. So, missed some details but gained better sound stage.

For now, I decided to stay with firmware 1.2.10. The missing sound details are only noticeable when I did critical listening. For listening to music while working, I couldn’t tell any quality drop, and I much appreciated the stable Bluetooth connection and the fact that I don’t feel strangely depressed after the listening session. Hopefully the upcoming firmware release will make things even better.

QC 35 promises 20 hours of wireless music listening, or 40 hours in wired mode. I have not fully tested this claim because all the firmware changes required me to plug in the headphones, and therefore had them charged. However, at the end of 3+ hours of wireless use, the voice feedback told me I still have 80% battery, that sounds about right.

Overall, very happy with this purchase. This is a product worthy of Bose’s name and reputation.