[Mansour] was disappointed to find out that his Bose QC15 headphones had a dead right channel. These headphones have active noise cancelling, which uses a microphone to capture ambient noise and digital signal processing to insert an out of phase signal. Since they’re quite expensive, [Mansour] was determined to resurrect them.
First, he determined that the right speaker had died, so he found a replacement on eBay. These were designed for a different set of headphones, but matched the impedance of the original Bose part. After replacing the driver, it seemed that the repair was a failure. The sound cancelling wasn’t working, and a the playback was high-pitched. As a last attempt, he potted the speaker with glue, to match the original construction. Much to his surprise, this worked.
The problem was that the new driver didn’t have sufficient sound isolation from the microphone, which is meant to pick up passive noise. This feedback likely caused issues with the noise cancelling DSP. A little glue meant a $20 fix for a $400 pair of headphones.
not to nitpick, but I kind of doubt those use a DSP. Probably just an inverting amp. All those caps and inductors suggest analog signal processing to me. I could be wrong…
I could be just as wrong, but those capacitors and inductors could be parts of two (or more) switchmode power supplies, to create a symmetrical power supply from an asymmetrical supply like a battery, and possibly a separate supply for the digital circuit.
I’d think it would be fairly difficult to suppress the local feedback from the speaker back to the microphone, and to provide just the right amount of power and phase shift to cancel external noise, over a large frequency spectrum, with just analog processing. Even with a decent DSP, it doesn’t exactly seem trivial to me.
Well, presumably that’s why they cost so much. I have a pair of QC3s and after 5 years of fair use the fine plastic parts just crumbled and the pads skinned horribly, Still usable, though. Have had some problems with feedback and my phone not recognizing them probably because they present a higher-impedance load than passive headphones. So I’m thinking about modding them so I can bypass the fancy active electronics when needed.
You could build an adapter cable with a 3.5mm jack and socket connected straight through, with 33 ohm resistors between the signals and ground. That should provide the load your phone wants to see.
You can sew the earpiece covers on some models… QC2 perhaps? Not sure what model I have. Anyway, a few pictures of the process: http://people.renci.org/~escott/bose_headphone_repair/index.html . I’ve had to sew pretty much every inch of mine back together. And of course, the usual failure mode is that the plastic fails where the headband comes into the top of the cans. All in all, a pretty junky product for the (outrageous) price. Sure, they were a gift, but…
I just replaced my worn out earpiece covers for about $10 (ebay) and 5 minutes (following a Youtube instruction).
Intermittent cutting out of the right side of my QC15s brought me here, I have to tap it to get it to work.
First link, caption under that photo:
“All the IC goodies are on the reverse side.”
I actually disassembled the headphones again and there aren’t any significant chips on the other side. See the post for the new photo of the back side.
could you not just use the inverse of the input?? a hight speed not gate ?? why shift phase ?? I have little electrical engineering experience so I’m probably overlooking some obvious reason that would fail.
Shifting the phase 180 degrees is almost exactly the same as inverting the signal.
The ‘not gate’ you refer to is digital, but you’re dealing with analog signals. Also, you want to cancel out the ambient noise, i.e. what’s picked up by the microphone somewhere in the headphone shell. With that microphone signal the signal processor performs some trickery so that the result is a signal that is roughly the inverse of the amount of ambient noise that would pass through the headphones to reach your ears.
I would have contact BOSE customer service first.
Then fix it myself if that does not work.
Nice, its amazing how much useful stuff gets needlessky trashed these days because it needs a 2 dollar part.
I acquired some nice wireless headphones a while back because it had the “special” AAA batteries with conductive collar a third of the way along whose absence prevented the headphones from charging. Fixed:-)
As something between trashing it and fixing it, Bose will give you a new pair of QC15 headphones for $100 plus return of the old ones, at any time.
How does this work?
Any online links to this policy?
No links, but if you call customer service and ask, they’ll take care of you. I’ve done it twice.
Thanks Steve. I mentioned this in the blog post right before the recipe.
You know, if you are going to sell headphones for 400 bucks, you’d better make replacement parts available I say. It’s basic stuff.
Hack-a-Day-ers,
I’m an engineer for a company that provides In-Flight Entertainment systems to commercial airlines. The full-up system – servers, video displays, handset controllers, audio jacks, everything but the headphones because those are throwaway. Part of our system is an active noise-cancelling module. It works at least as well with $3 Chinese headsets as the Bose headphones on their own. It is all analog. No need to add DSPs other than to make it appear that the headphones are “worth” the $400 price tag.
I guess designing specifically for airplane noise can boost the performance of the system, but I find it hard to belive that a $3 headset can be very much effective in active noise cancelling. Would you be able to share any details about this In-Flight systems… like what is the perceived noise attenuatinon for each frequency range, where is the power supply located, MICs, etc.
If you could point us to a consumer piece of hardware that rivals this hardware, in particular in-ear QC20i (sounds like what you’re referencing is an in-ear) — please let me know! I have yet to find better, and obviously don’t way to pay $300.
Thanks for the info. I used the same technique to repair US Army Bose Triport Tactical (also with noise cancelling):
http://www.martinmelchior.be/2014/01/repairing-bose-triport-tactical.html
Thanks Martin for letting us know. I’ll link to your post.
Hi there, I wonder if anyone can help me. I am repairing a pair of this headphone where the negative terminal in the battery compartment was broken off so I wanted to know if someone knows where the wire from negative terminal enters the main earpiece unit. I would be grateful for any description or a close-up picture showing the wire going in from negative battery terminal.
Kind regards
Annie
In the photo on this page, look at the series of colored wires that are soldered on the right side of the board. The solder blob on the top right of number “2” is the battery’s negative.
My QC15’s have failed with no power. Tried fresh battery and checked battery housing as best I could. Can you suggest which points to connect to each other with a tester in order to determine where any break in the circuit might be?
First sorry about hit the report button on your question hope its better well ill share this your battery cleaned out right so I would say that its NOT touching each end the spring it might have moved this is on the open lid or your battery fluid got dried and know you must re move it stop am just sharing this I would get them looked at there is some one on ebay who repair base head phone and maybe he is the right place name affordable. Fonics
Mansour , I have just seen your posting to Annie Johnson (not related to me) and on my QC-15 the battery cap holding and connecting wire has disappeared, not clear how. Bose are not able to help but ebay is. From the battery cap there needs to be a cable to the earphone board. Could you share the pictures you spoken in your response to Annie with me. Then I will try and repair what Bose says is not offered.
many thanks and in hope
a friend for life.
Clivce Johnson
You can contact a repair service. Stop here is one from ebay they are at ebay & they are located in Colorado. Tooooooo they would be helpful too your needs
Hi there,
I was recently travelling and noticed, what appeared to be, my battery had exploded within my headphones. I tried to clean it out first with a q-tip and then a q-tip with some rubbing alcohol on it, but when I insert the AAA battery – my headphones no longer work :(
Does anyone know what I can do to troubleshoot this or maybe even replace that whole unit? Or will I have to replace my headphones… :(
This just happened to me also, so I have the same questions as you…
I figured out what the problem was for my QC-15 Headphones not powering up. Its definitly a design defect with this model. The problem is that the wire that runs from the battery compartment to the negative post on the door/hinge has a fatigue failure problem. Through many repetitions of opening and closing the door to change the battery you inadvertently cause the wire to snap, very similar to how a paper clip breaks when you bend it back and forth a bunch of times. The wire is pretty hard to see too because they have it pretty well hidden on the little hinged cover and it dissappears into the headphones maybe 3/4″ down from the edge of the hinge. You really have to look to see it.
What really gets my goat here is that it seems that quite a few people are experiencing an issue where the unit just fails to power up all of a sudden and end up sending the unit back to Bose for close to $100 for a “replacement”. That is just plain old robbery for an almost built in failure point on a pretty expensive pair of headphones. When they get your headphones in they replace one tiny wire and then ship them to the next customer for another hundred dollars. Its insane.
The only reason I found it was that it happened right after i changed the battery which got me thinking about what could have possibly happened just from changing the battery. SO check the negative post wire to see if its broken. Also its worth mentioning that the wire could be intact and still broken internally. Mine was just snapped right in half though.
Hi Ryan,
Can you post pics of the design defect? I am really upset with Bose, got of their customer support. The usual right QC15 side of the headphones has gone blank. If I tap, I hear a crackling sound with music for like a nano second and it dies on me.
I have no choice but to get this repaired. I have no experience in soldering and glueing like mentioned above and frankly it is all daunting. But, if what you say is true, perhaps I can be inspired to push myself in learning and fixing the fatigued wire from the negative terminally the battery to the soldering blob.
Has anyone had any issues with the qc25. They have done away with the battery.
Where you based btw? I am in London
My QC15 just doesn’t power up after I changed the battery and you were right! The wire was disconnected from the base of the spring! Now I just need to solder the wire back to where it was disconnected. Luckily I did not send it back for repair, Bose customer service actually suggested that I should buy a new pair with discount. That is ridiculous, the wire just disconnected by itself after opening the door. I agree, it is a defect. Happy dance!
Hi Ryan, I am glad I saw your comment. My QC15 just doesn’t power up after I changed the battery and you were right! The wire was disconnected from the base of the spring! Now I just need to solder the wire back to where it was disconnected. Luckily I did not send it back for repair, Bose customer service actually suggested that I should buy a new pair with discount. That is ridiculous, the wire just disconnected by itself after opening the door. I agree, it is a defect. *Happy dance!*
Hi
I recently got headband cushion from Bose hong kong for my QC3 headset. I could not find any videos or website as to how to replace. i saw some videos on youtube but they are having zip or buttons on style. whereas mine are original.
Can someone help me teach how to replace it ?
Really appreciate help in this hour of need.
My right speaker no longer works on Bose qc3 headphones how do I replace the speaker
So reading through these posts I also have the crackling noise on the right side of
My QC15 headphones. Was there an easy fix for this that doesn’t require soldering it or shall I take the plunge and contact Bose Customer Service and go through that rigmarole to get them repaired/replaced. They are about three years old but every well looked after.
I am based in the UK.
I have a QC15 bought about two years ago. Just reporting that I have also lost sound on the right side. Started out as intermittent sound drop out. Sound could be restored by tapping the housing on the right side. Called Bose customer support and was informed that for $119 they would replace the headset. I decided to try and fix the unit. I opened up the right side and could see nothing loose. I simply pushed on the wires to see if any were loose and put the unit back together. The headset works a bit better now. Tapping the right side when it drops out brings the sound back; however shaking my head around causes sound to drop in and out. I am suspecting that the power switch is defective but I’m not sure.
@RS , I have the same thing happening to my QC25. Exactly the same. Not sure what to do. Lucky it’s still under guarantee. Opened it up, blew into it, and it’s a bit better.
Exactely the same today on my Q25 :(
No sound on the right side.
Tapping on the right side the sound come and go…
Any idea?
(Italy)
Problem solved.
daniele,
how was your problem solved? I have the same on my QC15s
Tim.
I thought I would share my experience here briefly. I have a set of QC15s, that are 7 years old now. One day, as I’m sure many of you have experienced, I snagged the headphone cord on something, and ripped the plug out from the left headphone. When I shoved it back in, I lost sound in the left side. A little jiggling of the plug and the sound would come and go. I first assumed it had something to do with the original cord. But after extensively checking the cord/plug with my volt meter, I could find nothing electrically wrong. I next opened up the left side of the headphones, and repeated the same process, looking for a broken connection in the plug receiver, or the wires going the the circuit board – nothing. Finally, left with little other option than to scrap the headphones, I checked the speaker itself and BINGO. My meter showed an open circuit, where it should have read around 33ohms (verified by doing the same test on the right speaker). I googled, and was able to find a guy selling a single speaker from the UK. And after following the OP’s instructions about sealing the speaker in place, the left side came back to life. I couldn’t be happier!
Long story short, check the speaker!
I had the left speaker die shortly after the warranty ran out on my QC25s. I did the same thing as in this article and it worked fine. About a year later the right side died. Tried to do the same fix there, but though I could get the speaker working when I turn on the noise cancelling I get a very loud high pitched tone (similar to the feedback you get when a microphone sits in front of a speaker). I’ve tried sealing with extra glue to no effect. Guess it’s time to retire them and find something else (definitely not buying Bose again though).
Hi,
How does one have to proceed to open the headphone?
And many QC15 and QC25 fans may well get issues with the right-hand headphone speaker cutting in and out, and whilst there are many YouTube vids out there explaining the easy fix, there may well come a time when even this stops working. Never fear. I have found a repair service that most definitely will look at fixing them at a very reasonable price. No need to go for that expensive trade-in deal unless they really are not fixable.
Electronic Partners https://uk.electronic.partners/. Free registration. Use their Customer Portal https://support.uk.electronic.partners/index.php for the smooth step-by-step process – get a quote estimate, book repair, receive repair request submission, order confirmation shipping label, check-in confirmation, repair request completed, proforma invoice, payment online with easypay.express, tracked return.
£41.90: £18.20 headphone replacement driver, £16.80 labour, £6.90 shipping and handling.
5-stars out of 5-stars. 10-stars out of 10-stars. I’d give more stars if I could. Most definitely the best option out there for repairing your Bose QC15 and Bose QC 25.
I was able to figure out my issue (didn’t fix yet!). When I tap the headphones, the sound cuts out. I think it’s due to the switch. To diagnose, take off the earpad for the right ear, and cloth cover. Then remove the 4 screws to take off the 2-piece silver cover. Then, put in the battery, play music. Now, wiggle or gently push in the power switch. If it makes the sound cut out, or if it makes the power light momentarily cut out, then it’s likely a bad switch.
touching my QC 15 (or tapping on them) cases them to ‘click’, lose their noise-cancelling feature, and then go back to normal. I’ve also noticed this when aircraft noise get really high (like take off / landing).
Mic problems? or what?