Beyerdynamic T51p repair

Arseni Mourzenko
Founder and lead developer
March 13, 2021
Tags: hardware 11 short 50

Disclaimer: the following article explains an unauthorized modification of a product. The manipulation explained in the article voids the warranty. Do not attempt to do the same operation, unless you know what you're doing.

I own a Bey­er­dy­nam­ic T51p head­phones. I bought them in 2017, and a few months af­ter its war­ran­ty ex­pired, it start­ed to ex­pe­ri­ence a com­mon prob­lem for this mod­el: the right dri­ver would work only when the wire was put in a spe­cif­ic po­si­tion. A few months lat­er, it sim­ply stopped work­ing. In fact, the head­phones use a very thin ca­ble, and it seems that the ca­ble broke.

I haven't used the head­phones for a while, but re­cent­ly, I fi­nal­ly con­tact­ed Bey­er­dy­nam­ic in or­der to know how much would it cost to re­pair the head­phones. From a com­pa­ny spe­cial­ized in rather ex­pen­sive prod­ucts, the ex­pe­ri­ence when it comes to ser­vic­ing their prod­ucts is rather dis­ap­point­ing. It looks like they hate be­ing con­tact­ed about the prob­lems with their prod­ucts, so they made the user ex­pe­ri­ence as mis­er­able as pos­si­ble. For in­stance, you have to fill a form (which, among oth­ers, in­cludes manda­to­ry fields that I can't fill, as well as stuff in Ger­man), and then you have to do it again in an Ex­cel file they ask you to down­load, fill, and up­load. Ei­ther they have nev­er heard of the fact that a script can gen­er­ate the Ex­cel file au­to­mat­i­cal­ly, or they re­al­ly want to make their cus­tomers' lives mis­er­able.

Then it got worse. I was con­tact­ed by some com­pa­ny with an un­clear af­fil­i­a­tion to Bey­er­dy­nam­ic, and was told to send my re­quest to an email ad­dress end­ing by “or­,” Or­ange be­ing a French ISP (so es­sen­tial­ly this some­one is un­able for some rea­son to pay Google $12 per year to get a do­main name!) The only rea­son why the per­son would con­tact me just to ask to con­tact some­one else (in­stead of for­ward­ing the orig­i­nal re­quest, like any per­son would do) is to make me feel mis­er­able one more time. I'm thank­ful for that.

I con­tact­ed the oth­er per­son, who an­swered that I can al­ways send him my head­phones, but he would give a price es­ti­mate only af­ter he sees the head­phones (not sure what he ex­pect­ed to see, as my de­scrip­tion of the prob­lem was clear enough). He spec­i­fied, how­ev­er, that a min­i­mum of €30 would be asked, which es­sen­tial­ly means, as I un­der­stand it, that if I send him the head­phones, and then I don't ac­cept his es­ti­mate (which could pos­si­bly ex­ceed the cost of the new head­phones), he would then send it back with­out re­pair­ing it, but would still re­quest €30 to be paid.

I there­fore de­cid­ed to ser­vice the head­phones my­self. Not only was it with­out ad­di­tion­al cost (as I al­ready have the spare ca­bles), but it also al­lowed me to do three things: use a bet­ter, more sol­id ca­ble, have a longer one, and get rid of the Y split that I find par­tic­u­lar­ly an­noy­ing.

The ma­jor is­sue is to re­move the dri­vers. One fo­rum dis­cus­sion is specif­i­cal­ly about that, and I got the very same prob­lem the orig­i­nal poster had: the dri­vers wouldn't pop out no mat­ter how long I tried. The hint was to use a screw­driv­er and to in­ten­tion­al­ly dam­age the side of the dri­ver. This way, I could in­sert the screw­driv­er fur­ther in, and fi­nal­ly won. A fun­ny thing is that I also (un­in­ten­tion­al­ly) made a hole in the fab­ric, just like the au­thor from the fo­rum dis­cus­sion:

I should have drilled a hole, like the fo­rum thread sug­gest­ed: ac­tu­al­ly, you can no­tice that this is just a piece of plas­tic, and there is noth­ing on the oth­er side:

The warn­ing about air vent­ing doesn't seem to be valid here, as there are al­ready holes in the cas­ing any­way:

The in­side of the head­phones looks like this. I'm sur­prised to see how small are the dri­vers com­pared to the cas­ing it­self. I'm not sure whether this is be­cause the dri­vers need some air space be­hind them, or this is all about the de­sign of the prod­uct.

Orig­i­nal­ly, I was be­liev­ing that the prob­lem is not the ca­ble, but the sol­der­ing. Test­ing it with a mul­ti­me­ter, it ap­peared that the sol­der­ing was all good, and it was the ca­ble which caused prob­lems. This made no dif­fer­ence for me, since I want­ed to re­place the ca­ble any­way.

Sol­der­ing was ac­tu­al­ly quite chal­leng­ing. Since the dri­ver is a large mag­net, it at­tracts the sol­der­ing iron. And if the iron touch­es its sur­face, well... the mag­net burns.

As I said, I hat­ed the orig­i­nal Y split de­sign, so I de­cid­ed to put a short two-wire ca­ble which would go from the left cas­ing to the right one. This is es­sen­tial­ly what I have with my ex­cel­lent Sony MDR-7506 mon­i­tor head­phones. Sony's ones have the wire go in­side the struc­ture. Bey­er­dy­nam­ic ones have a nar­row struc­ture which wouldn't al­low that, so in­stead I de­cid­ed to put it this way:

Looks ugly, but works well.

Here's the as­sem­bled ver­sion:

The fix­ing of the ca­ble go­ing from the left to the right side: