Bose QuietComfort 25 Headphones

There seems to be a lot of issues with the sound quality for these 2nd gen Bose phones.
These came out before wireless headphones were in any significant use, and when few other companies were making a serious attempt at noise reduction.
Given the parameters that Bose used, which was the best travel headphones and good quality audio, I know they succeeded and excelled over other products. 
In fact they had no real competitors for quite some time. Virtually every review was glowing, and considered them the gold standard. 
Today, is seems unfair to judge them against other products, with a higher price, and with years of development to improve on the Bose product. Or, against wireless head phones. 
Taken just on their original merits, and in the time frame they were introduced in, these were unbeatable. I feel that for the money they are still a best buy.
The absolutely have amazing noise reduction capabilities. They have unparalleled battery life, and not insignificantly, use replaceable AAA batteries.
Their portability, by which I mean the beautifully designed case they fold into, is top notch. The case even has room for a spare battery and airline jack. Possibly the standard for well designed cases.
Here's the test- take a flight, carry these along, plug in your own source, and even use an amp. You will be very pleased. It's that simple.
Do not expect to get the best possible audio, since you are in a noisy environment.
Do not expect them to compete with newly designed $400 head phones. That's not even logical. They were engineered years ago and yet are still excellent for traveling.

i got mine for a reasonable price of only $150 and love them but a Headphone amp really improves the experience

I bought the Quiet Comfort 25's from Bose, last year and used them for about two months before selling them.
No DAC, DAP, or any special kind of amp. I plugged them in the headphone jack of my cellphone and listened to music. 
 
The first thing I noticed, outside of Best Buy, walking back home with the headphones on my head, really pissed me off.
I don't know if I had a damaged product, or if I didn't wear the headphones properly, but whenever I walked a step, the music would 
cut off for a second. 
That was a huge problem.
 
Secondly, something else that really bothered me was the fact that the sound cancellation really hurt my head.
I had the kind of pain some people have when you're on an airplane going up and your ears get clogged.
After a couple of weeks, the pain ceased, but I still felt a difference whenever I would turn on that cancellation switch.
 
The sound cancellation sucked too. At first it was amazing, but after a week, my ears heard everything, even with cancellation turned on
It's as if my ears had adapted to the cancellation and found a way to bypass it or something. 
 
The third and last thing that really annoyed me was the cable, the cable was really long.
It would get caught with my knee and then I'd yank it from the jack accidentally.
In addition, Bose made sure that if you decided to replace the cable, you'd have to buy it from them 
and don't fool yourself, you will eventually have to replace it.
 
The cable wasn't male to male. It was male to Bose, if you get what I mean. 
 
Anyway, let's put the cons aside.
 
What was great about the QC 25's was definitely how portable they were. 
Although the case wasn't really practical, the fact that they could roll into a ball shape 
made it take less space than any other headphone I've had.
 
Still, the cons outweighed the pros and is the reason why I believe the QC 25's aren't worth 300$.

I have considerable experience in headphones, having owned: AKG K702s (poor finish with loose wire mesh on earpieces. Too large and heavy), Sennheiser 202 (Okish sound but claustrophobic feeling and much too much bass), Beyerdynamic DT 990 Premium Edition (nice all round sound and quality but I caught the 100 metre (that's what iit seemed like) in my wheelchair and couldn't find anyone who could fix them (never buy headphones with fixed cables), Beyerdynamic DT 860, I generally liked these until I sat on them resulting in compressed sound (joke) and broken head band (no joke)! I have also owned bottom end and high end Grados but can only remember the crap build quality and discomfort, they left my head slightly narrower than before, this allied to manufacturers faults cured me of my desire to own 'real hi-fi phones with terrific reviews). I can't remember any more proper headphones but have owned Shure in ear, Bang & Olufsen, and many others. None would feel comfortable or stay in my ears except the rather good Bose range which I still use and are as comfortable and musical as in ear phones get.

You might get the impression that I am biased towards Bose. I can only say I used to think their products over priced tat however I found I liked their products. They make the small ST 10 which I use in my room in the nursing home, there not being space for my new Sony connected, multi hard drive system. I also have three other small wireless Bose speakers. The build quality of their produts is beautiful. They look and feel like craftsman built items and weigh a lot more than their size suggessts.

I had accumulated 7 Bose in ear phones over the years each eventually falling foul of my wheel or powe recliner chairs. No receipts and in one case even the hologram sticker missing I took themin to the Cabot Circus Bose shop in Bristol and was amazed when they, without any drama, handed me 7 new earphones. Yes, I like Bose.

The QC 25s cost a lot less than many phones I have owned and don't really look like an audiophile product. They are unapologetically plastic with metal ear cover things. The plastc feels and looks good, I particularly like he white with turquoise accents. They immediately felt right on my ears and the noise reduction creates a black soundstage just like ou hear immediately before the Tallis Scholars light up Bath Cathedral. Yes, I listen mainly to early choral music, as well as modern classical and pop. And I can't fault these phones at all.

The noise canceling on these is the industry's best. The sound quality is better than expected and quite listenable, although could be slightly better. I decided to do a view review of these here: 
 
 

After going through many headphones, including the Bowers & Wilkins C5 S2, Bowers & Wilkins P3, Sennheiser Momentum M2 AEi as well as a pair of Westone W40s, I'm mightily impressed by the Bose QC25. It offers fantastic noise cancellation, exceptional sound quality (even for a non-ANC headphone) and is in general an excellent product.
In short, I will be reviewing:
1. Sound
2. Noise cancellation
3. Comfort and design
 
SOUND
Do not listen to these headphones without switching them on (this requires one AAA battery - lasts around 35 hours! I use a rechargable Eneloop AAA battery). However, they sound pretty good if the ANC is turned on, which activates the internal electronics which electronically equalise the sound signals.
 
The bass, mid and highs are tonally balanced and suffers from no excessive bloating or dips in the frequency response. This is pretty good for a noise cancelling headphones. The bass response is tight and clear, exceptionally well-done for an ANC headphone. The slight lack of dynamic range (compared to non-ANC headphones) is a minor issue as well in some tracks. With a good amp (I personally use the Oppo HA-2), the dynamic range increases by a slight degree. The sound, however, is pleasant to listen to from portable devices as well.
 

Bose QC25 being driven by my Oppo HA-2 DAC/AMP
 
However, the sound is tonally balanced and sound-staging is above average for an closed-back headphone. Mid and highs sound really good when listening to saxophone music or any music with less bass.  However, this headphone can make all music genres sound acceptable without leaning towards any part of the frequencies. The neutral and deeply extended bass is extremely well controlled. It suits my music tastes very well. Upper mids/lower treble is very present, only lacks the last bit of upper treble extension (only found in open-backed headphones) but clarity is again very good.
 
Bass: Very good bass extension. Extremely tight, well-controlled. Much better than my Momentums. In combination with the ANC, bass is VERY clear and well-defined. Suits all genres of music pretty well.
Mids: Open, very natural. The mids are very realistic, with a slight peak at the 3kHz region. This makes the headphone sound forward sounding and is exceptional for vocals. I can hear no dips/anomalies in the mids.
Treble: Treble is well extended into the lower treble. Soundstage and a sense of space is clearly defined. For a closed-back headphone, the treble is very well extended indeed. For an ANC headphone, this is simply exceptional. Treble is slightly rolled-off to prevent listening fatigue. Perhaps this is the only area which Bose could improve a bit on for the next QC headphone.
 
NOISE CANCELLATION
Noise cancellation is, as usual, excellent. These were my first pair of ANC headphones and I wore them on a 13-hour flight to London, so here's what I found:
1. Dramatically reduces low frequency noises as usual.
 
2. Mid to high frequency noises are blocked out mostly by the headphone's acoustic seal (i.e. earpads) rather than the noise cancellation electronics. Some higher pitched air-con noises may leak in, however they are still dramatically reduced because of the acoustic seal.
 
3. If you are wearing glasses, this makes a difference. You will let in more noise because the acoustic seal is not perfectly sealed to your head. On the flight, I was taking off my glasses to sleep and noticed how much of a difference it made by simply not wearing glasses. This is because the acoustic seal doesn't seal completely if you wear glasses. I would estimate a further 3-4dB of noise was eliminated just by taking off my glasses. So if you are glasses user, be aware. Glasses, however, do not change the bass response much because Bose's internal DSP is able to compensate for the bass response unlike normal tightly sealed closed-back headphones.
 
COMFORT AND DESIGN
Personally I love the understated and brushed aluminium ear cups. They look industrial, durable and sleek. The headphone comes with a hard carrying case which is also rather understated but is very durable and functional for portable use. This headphone is really light and wearing them for long periods of time is painless compared to head-clamps like Beats by Dre.
 
A fair amount of plastic has gone into the construction of this headphone. Some might argue this means it might feel cheap or not durable. With the Bose QC25, this is totally not true! However, I would say that the plastic gives a solid and sleek feel to the design, and helps it maintain its light weight, making the headphone both feel truly portable and durable. Need I say more? Bose uses aerospace-grade plastic in all their headphones. The cable included is compatible with iDevices or Android devices whichever you choose, and the cable feels thick and durable enough to last for a long time. Cable has a 90-degree 3.5mm jack and is made of durable plastic.
 
CONCLUSION
I highly recommend these headphones to any traveller (even those with glasses). The mixture of sleek design, excellent comfort, superb noise cancellation and good sound make the Bose QC25 an exceptional headphone for home and portable use. It's just the bass and dynamic range that is slightly lacking! Well, compared to the QC20 (the in-ear version of Bose's noise cancelling headphones), I find the QC25 to be a better choice due to better bass performance and soundstaging, as well as none of that awkward "control module" hanging at the end of the cable (as is the case with QC20). Whilst the QC20 might be a better option for those seeking true portability since it fits into a very small case compared to the QC25, the QC25 is in every way better since, after all, it is a full size over-ear headphone!
The QC25 is well worth the $299 retail price for its sound, noise cancellation and design. Do give it a shot and see what you think!

I had a pair of Bose on ears for many years.  They were my goto for editing Youtube movies since they can be worn all day without pain or sweat.  For critical listening in a quiet room, I would never pick it over my Audeze, Sennheiser, Fostex, AKG or Stax headphones.  Then a month ago, I tried a pair of Bose QC25 at a company showcase store in San Francisco.  A pair of Sennheiser Momentum 2 Wireless and iPhone 6 plus were with me at the time.  Not only did I prefer the musicality of the QC25 over the M2 for the tracks I tried, the comfort and the noise canceling of the QC25 was clearly superior to my M2.
I was stunned.
 
Tonight as I write this in the middle of summer in New York.  The AC is blowing on my right side. Normally, I would be watching cable TV but with the QC25, I can enjoy music. At this moment Jazz at the Pawnshop. I can enjoy the beautiful alto sax and clarinet as if I were in that smoky Jazz club back in 1976 Stockholm Sweden.
The imaging is forward with good space in front and beyond both ears.  After some time, the QC25 disappears.  I really feel like I was sitting at the bar.
I never get that with the Audeze LCD3, my favorite for classical pieces.  In a perfect world, the Audeze should be light and comfortable as the QC25.
Of course, the QC25 cannot play Bach Toccata & Fugue like a LCD3, but I was surprised how the Bose handle the low end without adding any color.  With the active noise canceling, I felt the spatial dimensionality of the Los Angeles First Congregational Church as the headphone floated off my head.
It's nearly like sitting at the pews.
Besides jazz and classical, the QC25 handles vocals wonderfully. Again, with the NC there is just the performer and I in the room.
 
Count this listener truly impressed.

I have bought both the 20i in Ears from Bose and the QC 25. The 20i in ears Noise Cancelation eats the QC25 NC for breakfast. Seriously, they are in another ball park. The 20i NC works like on pro-levels and let the NC in the QC25 seem like a Kindergarten toy across the whole frequency spectrum, the 20i cancelled noise better, a lot better, let it be water, clicking, birds, wind, voices, knocks, doors slamming. Whatever I threw at both of them, the QC25 did let through about 50% of the sound and the 20i about 25% of exterior sound, yes the 20i it is that good. So - if you are serious about NC better give the 20i in ears a try.
 
That being said, the sound on the QC25 is substantially nicer, the bass extends more, the soundstage is bigger and there is a more detail in comparison. I would even say I enjoy its relaxed, muffled down sound signature. But the sound is boring, very flat, very streamlined and unengaging. Highs are the most undynamic I ever heard, mids and voices are a bit better and bass is very strong, too much of it.
 
I would never hesitate to opt for my Beyerdynamics which sound-wise is just no comparison to Bose products, which is unfair I know, Bose being cool overpriced and well-made gadgets and Beyer T51p being a serious headphone for adults. Fyi All A/B tests were done against an Audio Engine D1 DAC.
 
Then there is the ground level white noise, which is much louder with the 20i, almost making me hate them. Also the "pressure" we know from NC is much more on the QC25, but its bearable. Before I make a decision which one to keep I will take them to work. Because of much less leakage and far superiour NC I will probably opt for the 20i or as an complete alternative for some cIEMs made out of silicon.
 
Comfort-wise the QC25 is quite great, light and with great haptics. Materials are excellent, but they will get sweaty.

After looking, testing and testing some moreI upgraded to the QC25 from Sennheisers PXC 250. I travel frequently and love noise canceling headphones on any air trip. NC is much better than on the Sennheiser and I personally love the sound quality; I'm a music lover, not an audiophile and for me these headphones provide a very good reproduction on the wide range of music I like. Whether it's classical, blues, jazz, R&B or some firmer guitar music; all are a joy to my ears. Build quality of headphone, cable and case seem very good but will have to prove themselves over the coming years. If they serve me as long and well as the PXC 250's, I'm more than happy.
 
I've had one battery run out of juice because I stored the headphones in their case without noticing it was still on and that's probably the only thing I liked better on the PXC 250's; the large red LED on that just attracted more attention than the tiny green light on the QC25. So far that's the only real con; headphones are always hard to use if you want to lay on one ear, but as I never get paid to fly business class I guess it's more of a hypothetical problem than a practical one. The 6,3mm adapter would've been nice but hardly neccessary; I can manage well without.
 
Two remarks about the price I paid; it's a converted price in Euro, and it was a downpriced unit from an online seller (probably a returned unit not deemed entirely new anymore) on which I got a full Norwegian VAT refund (25%). Coincidence of anyone to pull that off in the same manner is rather small I guess

Please note that its my first reviev, if i gave unclear or incomplete information feel free to ask.
 
Comfort is alright not the most comfortable headpones i've worn.The pressure gets unpleasant after wearing for longer than an hour but it isn't bad enough to concider it a game breaker.
Sound quality is alright, I havent notice any frequency to sound significantly better or worse but compared to my HD 558 the sound seems to come out of an cardbord tube.
I see no sense in buying this headphones  unless you will be frquently using them in very noisy envirement for moderately noisy envirement i would reccomend the B&W P7 that still isolate very well but simply DESTROY the QC 25 in terms of sound quality.

For years I have been told by Head Fi members that never get Bose, Bose sucks, Bose is overpriced and I completely ignored Bose. Always managed my long flights with in-ear monitors (Westone 3) but living in NYC, the passive Noise cancelling just wasnt cutting it for me. I always liked the noise cancelling and comfort factor of Bose QC15 but never really thought the sound was fulfilling minimum requirements in sound quality department for me. I needed a change since over the past 2 years I have been travelling continents and after reading every opinion on active noise cancelling and its benefits I bought them.

(I was gifted Sony NC500 headphones and used them for a while but I have nothing good to say about them so I won’t bother unless someone asks)

Then I read about QC25 and a long 22 hour flight was coming so I had to make a decision…let it be a miserable flight with noisy babies and passengers or trust the frequent flyers around the world and buy Bose.
Other Active Noise cancelling headphones were out of the question because they just cannot compete on comfort and noise reduction. The question was of sound signature and and improvements.

To keep things short, Bose QC25 are probably the best noise cancelling headphones if one takes all factors into account including Sound quality.


Design : Understated grey design fits my personality instead of ‘look at me’ design of Beats and other effeminate headphones.The minor blue color detail goes very well with greys. The swivel earcups really reduce the size profile and very easy to stow in the pockets of the coach class seats. They are very light but yet feel very solid. 
They never feel fragile and have not prone to scratches on the earcups.
there is no such thing as a kit for these headphones, its just the hard case and the headphones. There is a small slot for Airline adaptor and extra cell.
- Cable has inline remote that works perfectly with my new iphone 6 and macbook pro but does not work with my Lumia 920.
- Extremely comfortable without a doubt and slept like a baby in the flight by using them as earmuffs.
- Works without battery as normal headphones also in case of emergency but sounds like a $10 chinese headphone in that mode. They should def include Bose QC25 in the next Transformers movie.

Performance: I have been using these since 30th October when I received them from Amazon and today is 14th November and even after using 80% of the time on my New York to Singapore flight via Dubai, they are still running on the same AAA battery.
I was told that when 7 hours are left on them, the non-eye piercing green LED starts blinking but its still static.
The biggest anxiety I have with rechargeable headphones is not knowing when battery will run out. But with Bose QC25, the replaceable battery feature really is an improvement and you will appreciate it.
 Note For QC15 Owners: The Hi/Low feature still exists but it has been moved to the airline adaptor. This means that the airline adaptor used with single 3.5mm pin acts as an impedance adaptor. I have used it on my speakers output and it does work.
- They definitely benefit a lot of amplifier, with iBasso D2 Boa plugged into my macbook pro, the bass and dynamic range benefitted but then the sound also became a bit too forward for long duration listening.

Noise Cancelling performance: To give you an idea, I was in A380 and when I put them on and switched them on, I felt like I was in alaska with 2-3 people talking in the next house. Could not hear any ambient noise at all. This was a very strange feeling for me as I have never used Bose on a flight. Its as if their entire R&D team  has rented a lab next to Airbus factory and know exactly what frequencies need to be cancelled.

Sound Quality: Definitely a big improvement over QC 15 in terms of midrange and highs have lot of more details and being a bit more forward, you never feel you are missing out on some frequencies.
the bass is laid back in the beginning but I will get back to it in a while.

I have now tested Bose QC 25 with Sennheiser HD600 and Westone 3 side by side with some of my favorite tracks and some popular poppy music.

(All songs were 320 Kbps Mp3 and played out of Macbook Pro 15 inch and Cowon J3 in between)
Song: Bright Lights - Gary Clark Jr.
Every minor detail in the background is captured including some other sounds in the studio and friction on the guitar string. No distortion. Good stereo imaging and the DSP’s add a good feel of soundstage. The snaps sound very good even when compared to amplified HD600 but of course there is a lack of dynamic range in the output (I am not sure how the driver system works in Active NC but this is the main weakness)

Song: Maps - Maroon 5
Definitely the bass comes out here but the recording is so terrible that there is hardly any dynamic range in the song and everything sounds at same level even with HD600. Adam Levine you should be ashamed.

Song: Ain’t no Love in the heart of the city - Bobby Blue Bland
Very accurate stereo separation of vocals, drum kits, strums. The dynamic range is definitely lacking which constitutes to poorly perceived weight of bass but vocals sound very clean with very low sibilance.
They are forgiving on sibilance when Westone 3 only harshly reveal sibilance in recordings.

Song: Sail - Awolnation
The highs are there but never fatiguing. Stereo imaging is accurate, the different basses are differentiated and no muddiness. although vocals sound more laid back than HD600 or Westone 3.

Song: TKO Remix - Justin Timberlake
the dynamic range is slightly better on this song and seems like they do well with other Justin Timberlake songs as well..strange.


 
 
Cliffs: 
 
- Big improvement in Sound quality and simple but thoughtful design (much like BMW, everything is understated)
- Designed with frequent flyer in mind at every instance but been enjoying them at home as well due to never ending battery life.
- Not as bassy as beats but good separation on different low end frequencies and with EQ they became very good for bassy music.
- Dynamic range is lacking that gives those eargasms but with headphone amplifier that also improves a lot.
- Noise cancelling is impeccable and had the best sleep on my flight even though it was a very noisy flight overall.
- Put them on and you are in your own private soundroom.

Well, the main reason for this review is that these have been in and out of my grasp at least once (as in I've had them, then debated and lost against myself at keeping them and gave them back) At very least, I thought I'd share my thoughts on them against what are the legendary QC15s to help everyone out a little bit. So.....let's go!
 
Design (and Portability)
 
A very useful and notable change with the QC25s (other than the change to how they look) is that they fold inside to help them fit into their smaller case compared to the QC15s, with a case that will fit them to the extent that they can fold; flat, not inside. Also, the case has a purpose made space for the airline adapter and spare battery you'd most probably (and I'd reccomend you to) take with you.
 

From left to right: QC15 Case, QC25 Case
 
 
 
The QC25s' case being smaller does make it slightly easier to put in a bag and take around with you, especially if space is a premium on any long trips, although if you're travel is the hour or two of commuting to work on the train then you may not notice a huge real-life difference between the two. The main reason the smaller case is both a pro and a con is that inside the new case, after the headphone (folded) is in there and you've got the cable to sit somewhere nice, there's only really space for one spare battery and the airline adapter, whereas in the QC15 case, you have a little pocket that can hold quite a few (I count 5 or so) AAA batteries, and the void where the headphones are still nets you some space for a cable, and maybe some jack adapters and your airline adapter too.
 
Other than the case, the QC25s opt for a fabric cover on the headband as opposed to the leather that the QC15s had, and a black-and-blue striped liner inside the earpads, with a huge L or R on them. The second is something I don't like when looking at them, but perfectly honest is something that's a bit of a non-problem, because nobody (including you) will see them once you're wearing them. Also, the QC25 come in white and cream, or black and slate. At least there's a choice rather than having to wait for limited editions to the "anything, as long as it's silver" on the QC15. They also use a simpler cable that doesn't have, or need, overmolds to fit in to the shape of the headphone. The cable's thicker as well, although now you have to have a remote and mic cable with them. I can see an issue with earlier Android devices that may decide not to output audio to them. Best bet is to try a set with your phone before buying just in case.
 
The cable is still removable but these aren't wireless for audio. You can use them for my sleeping analogy (especially sleeping while travelling if you're brave) in noise cancelling mode without the cable, but if you want some tasty beats, you'll want that cable in
 
Comfort
 
Comfort between the two is pretty similar. Never a bad thing with what I could easily class as some of the most comfortable headphones I've used, and tried. 15s are good when I need to make sure I'm getting good rest so I still look "acceptable" while there's a party next door and I could easily imagine doing the same with 25s. The QC25s ear pads feel slightly different, and clamping force feels ever so slightly tougher on the 25s, but that could easily be attributed to new vs "weathered" sets of headphones. I still wouldn't call these "uncomfortable" in any way, even after a long listening session at home or out and about.
 
Features
 
25s work when they're off! If I'm honest, I personally am not excited a huge amount about this. Yeah, they work when they're off but think of it this way. QC25s and QC15s last for arouns 25-35 hours on a single AAA. If you have a spare battery/spare batteries with you, you're minimum looking at around 55-70 hours of play time with them. That's difficult to burn through unless you forget to turn them off and investing in some good rechargables (eneloops) will mean you're hardly every gonna use them when they're off. This is the non-caveat I have with QC15s and why I prefer they're larger case. I can take three or four of my spare eneloops as well as the one in the headphone with me. Total time - 150-170 hours over 5 batteries. I struggle to be completely out of battery with them, so I never "run out forever." With 25s, you can maybe get three (if you don't mind leaving the battery loose and knocking next to the heaphones) batteries with you (one in the headphone, one in the insert, one somewhere in the case) so you can still get your decent 65-100 hours taking them with you. On a day out, unless you've used a lot of the battery life, you'll only need one.
 
Noise Cancellation
 
Here in London, we have one of the noisiest things in the world. Yep, the Underground. QC15s are already quite good at cutting through most of the background noise and putting your music front and center. On the noisier parts of the tube, the spikes from outside will still seep in, but if you're volumes at a semi-decent level (halfway on my iPhone 5) it really won't bother you. This is where the 25s start to show off what they can do. They're quieter - much quieter. The tube is challenging for lots of things because the sound is never constant, but if the 15s slightly push those spikes back, the 25s do that slightly further, and smooth over them a little bit more. You're music definitely feels more present when there's lots of disruptive noise.
 
I haven't had the financial opportunity to try them on a plane, although I'd imagine that with the constant sound you get on both, you'd mainly see the 25s will definitely quieten down the engine a lot more then 15s will. It's not chalk and cheese, but I'd much rather have a plate of 25 if this was the only metric.
 
Sound
 
This is the deciding one. How do these headphones stack up compared to the 15s. Remember people, this is very subjective, so let me explain my music taste. I'm on the side of R&B, Soul, Hip-Hop and the like, as well as a bit of Jazz, Classical, and probably some Electronic music thrown in there. I'm definitely partial to the warmer, darker side of sound, with a bit of a bite in the midrange and treble, and that's what made me love the 15s. Neither of these are basshead, or analytical headphones as a quick one; they're pleasant and most people will appreciate both of them.
 
The 25s still have that slight sharpness at the treble end, with a slight push forward on the bass response. On the bass response, they're a bit on the loose side compared to other things I've listened to. Voices can sometimes get pushed back into the middle of the instrumentation if the track gives them the opportunity. It gives them a "nice" warm sound with a little bit of a snap to it.
 
With one of my favourite soul tracks, "Drive All Night" by Joss Stone, the kick drum definitely has that smoother punch I'd expect, while Stone's sultry voice still seems to float around slightly more front and center. There is nice refinement to her voice that does give it that slightly lifelike and live feel to make them quite enjoyable. Those keyboard sounds that you get in the background also float around, almost setting the scene of a purple jazz lounge in your head (and with my Afro, there's a lot of space in that lounge.....you guys want to visit?)
 
If you want bass, "A Dream Within A Dream" by The Glitch Mob can get them moving quite a lot of air in that little bubble they make. Soundstaging, the sense of space from the sound, is where a headphone can make this song sound awesome. At a midpoint in the song, a synthesized "saxophone" (if you can call it that) plays in the background. It doesn't seem to have an etheral feel to it as it has on many headphones I'll listen to with this song. They're not completely direct as in "shooting sound directly into your head" but the soungstage doesn't extend as far back as you imagine it could. Some of Bose's on-ear headphones will soundstage to a similar, if not only slightly lesser extent to these which is slightly scary. The bass response is controlled compared to a lot of other headphones in this bracket. Forward given the type of song, but with a fast enough decay not to get in the way of anything else which, with the amount of drums you have in this song, is great. The "glitchy guitar" (that's what I'm calling it!) has a slightly softened timbre to it. I like this, some people may want the slightly harsher sound thrown in. If you're the second type, a quick EQ on the higher frequencies should give that a quick fix.
 
To get more critical with them, with Nils Frahm's "Says," the texture of the synthesizer he's using just about comes through - remember these aren't analytical, there's definitely some detail that gets smoothed over - compared to what I'd get out of my Denon AH-D5000's at home - the Denon's are about one and a half times to twice as expensive though. This is quite a good thing in a way with this song because at moderately loud to loud volumes, it doesn't become completely unchained and assault you with what can be harsh tones on sharper headphones. The soundstaging from the headphones, although wider than expected, isn't as expansive as I thought it could be again. The notes on the synthesizer, especially as the song builds to the end, all seem to be coming from the same-ish place on the left and the right with the bass from the lower notes becoming, strangely, subtly pushed further back within the complex arrangement. The headphones are still enjoyable with this song unless you decide you want to listen critically, in which you turn into what I do; someone who looks for anything you didn't like (I had to re-listen a lot before these things started to get me)
 
Overall, for a Noise Canceller, these sound good enough to use as your dual use home headphone for many genres of music, as well as your travel, commute, and general "shut-up world" headphone. And they can become a very enjoyable headphone to have a listen to, with enough detail and push to get you through some semi-speedy rock music, as well as refinement that works well for your jazz or soul. You have enough punch for your electronic music too. The only thing you may not get is a huge soundstage. It's acceptable and will be "good enough" for most of your musical needs however.
 
How about when they're off?
 
When they're off, you'll lose a lot of the top end, and a lot of the bottom end. They'll sound slightly muffled. Bass won't be muddy, it'll just be reduced in it's overall quantity. This doesn't make them analytical, they're just not as clear and not as heavy. A lot of the soul that makes them legendary kind of goes away, so this isn't a mode you'll "want" to listen to, but one you'll listen to inbetween changes of batteries, or recharges of your eneloops or other rechargable AAAs
 
Sound - Compared to their Dad
 
25s replace 15s. 15s are definitely in two of my lists. They're my favourite Noise Cancelling headphone, and they're among my favourite headband style headphone with the only things better being those that are both more expensive and don't actively cancel noise. So, how are they when faced off against each other? Remember, this is my subjective afro-based opinion.
 
I prefer the 15s
 
Honestly, I listened to the 25s and felt that there was "something missing" rather than a difference. The 15s, although less forward with their bass, seemed to have a bit more refinement and a more laid back feel which I love. The detail on them was slightly better; the mids on the 15s seem a bit less forward than the 25s which doesn't mean you lose mids - it means you gain a bit more detail and crispness. Most important to me is that these both come in with a noticeably different soundstage. They're wide enough that you do feel that bit more immersed. To me, you gain utility but go sideways or, in my opinion, slightly downards in sound.
 
Summary - The "Short Review"
 
You're going to love the 25s, just as much as you'd love 15s if I'm completely honest with you. Best bet, if you have the opportunity go out and try them with your own stuff. My opinions are based on the fact that I'm particular with the sound of them, and that I still expect my NC headphones to blow my socks off. After having the 15s do that, I expect the same from the 25s and you probably won't get that. You're talking two headphones that are very similar. Once you pick one that becomes you're blueprint at this level of NC, and differences can easily become negative rather than positive.
 
I'd definitely say the foldability of the 25s is good, even if it means you can't fit as much into there now. The thicker cable also means you're gonna be spending less on maintenance on the headphones. The NC is also a big boost compared to what they've done before; enjoy the even quieter silence.
 
Sound wise, you've got a slightly more direct, less "dark" and more "warm" headphone compared to previous QC around ears. Soundstaging exists, it's just not as prominent as you may have previously experiences. An ever so slightly more "common denominator" rather than "niche" type of sound overall I would say. Minor differences to most of the community. Treble is still in the same amount in a way, if not slightly reduced, and you're mids and bass go up a bit more in quantity. Not basshead, but you end up with a less detailed and rounder sound as a result. When they're off, everything becomes masked under a cloud of not being powered (and therefore actively equalised)
 
Content with your 15s? You might be better off keeping them and spend that money on a new set of ear pads and a cable. (unless you try them and prefer the 25s) If you don't own either one, I'd say it'd be worth getting the 25s. The little additions for utility, ability to work when you've forgotten to charge up, and possibly more "universal" cable make them better than having to try to find a good condition 15.