Nice. Thanks for the feedback. I am planning on making a fancier mod for them next month hopefully so I will have a good play and do a load of tests with different configs

Thanks, nice to know fellow nerds are out there ;)

Unfortunately i think the only option will be to use a flat head screw driver or spudger to lever the driver out. If you did mark the aluminiun while prying it open, it would be in a place you could not see when it was back in one piece as the pad would be covering it

The effect is pretty subtle and it have been a long time since I tested it but from what I remember you get a little less upper treble with it in but it reduces the sound stage a little... As I said, it was pretty subtle, I just preferred the sound with it out

It would be down to personal taste, you may prefer the sound with the original felt disc. I think, as long as you are careful, there is not much risk. we sell hundreds of kits and have not had anyone kill a driver since this video was uploaded

We should have a copper version available in a few months

That sounds great i cant whait to put my order inn! Just a thought have you conssiderd using brass picesfor the mass loading? It is great for gounding vibrations in speakers fasteners, spikes etc.. I have used brass to mass loading the back of the cones on a pair of koss porta pro with great resualts they sound better at this point to me then the stock hd 25 that i own i my opinion and they have been kramer modded and i cut out a center hole on the pads and soon to be mmcx converted they sound more natural and more musical and just emotionaly pleasing at this point witch is cracy at that price... But i have stock hd25 no modding done yet but i ready to try ;-) @@CustomCans

I have both pairs and the Ireland made models I much prefer. I find the new model very boomy and not as crisp!

@@sebtaylor69 I think so

The mass loading has the most effect. The damping is very subtle

@@CustomCans i see that the mass loading kit uses lead, is there any safer alterantive?

It is just bitumen based sound deadening material. It should be available most places - it is often used on cars to reduce noise

Yes ... Not sure how long they need but even if they are the same version you can hear the difference between a nicely warn in pair and a box fresh pair... Maybe it had not left them burning in long enough. The link for the kit is now up in the description

Ah.... That red one is a focusrite scarlett but I will be using that for recording in a future project - the amp on top of that is the one I am using for testing and that is an SMSL SP200

Yes the amperior earcups will fit the older MKII HD25 drivers - the amperior used the same earcups and the HD25 aluminium. The latest HD25 drivers do not fit as tightly in the aluminium housings though

@@CustomCans thanks reply , ic , seems i need to got a old HD25ii (seems made in ireland better)

@@makeow Yes... If they have HD25-1 ii written in the small square in the centre of the left earcup then the drivers should fit. If it just has the sennheiser logo, then it is the newer driver. You can use the new drivers but may have to glue or tape them as they don't click in firmly enough

if you search for 6mm self adhesive lead you should find some

It does not make as much difference on the 1990s as the lower models as the drivers are already quite heavy

@@CustomCans Thanks, i just have to try it anyway as its so cheap. Balanced mod took a little bit of base away i felt but not by much. Maybe it just increased the sound stage elsewhere giving that illusion, who knows lol.