My Sennheiser HD 555 ear pads have worn out. But I just realised my 555 is nearly 20 yrs old.
What’s a good up/side-grade from the Sennheiser HD 555 around 10k?
Do I go with the similar 599 SE or are there better options? My preference is for the Sennheiser sound.
Also have a look at HD 560s. This has better imaging and tighter and more balanced tunning than 599/599 se.
The 599 has elevated mid-high bass along with more forward upper mids into the treble. It plateaus at 1k-2k so it trades the quality of the mids for a more dynamic V-shaped sound.
Although the 560s has terrible noise isolation, but that may be attributed to the open-back design.
I’ve heard nothing but good things about FiiO FT-1s if you extend your budget slightly more or find an used one…
This is a closed back headphone so the sound stage delivered by these wil be inferior to the open back design of Sennheiser 560s/599/599se/555.
OP has been driving open backs for past 20 years so they are accustomed to the wide sound stage and now shifting to close backs will be a major change for him
On plus point you will get way better sound insulation.
Though if ft-1 pro offers the same tunning as ft-1 then it can be considered as it’s a open back design.
You still get replacement ear-pads -
I’ve bought these replacements and also from another brand called Crysendo a couple times. Despite the cost, the inner stitching tears up in less than a year. And i take good care of my gear.
We don’t really have many options though. So it’s better to go for the cheapest option. 1.8k for this stuff is just too much.
Unfortunately old models don’t have much quality options unless you go custom, which will still be costly. The OEM sells aftermarket pads for some models so Senn India can be asked. Dekoni and Brainwavz makes decent pads but not sure if they stock this. According to this, other model pads may fit but ymmv. Perhaps OP can replace the earpads, sell it and get new headphones.
Rs 1.8k for two pieces of foam 
I have a HD 598 SE nearly 8 yrs old, the ear pads and headband have worn off and I am looking to replace them, but at these prices better to buy another headphone for 10k than replace the pads and headband for 4k
Also keep in mind you probably wouldn’t like how any replacement sounds for the first few hundred hours. Twenty years is basically a life spent with ever-sweetening sound, anything new would a drastic departure.
Back when I cared about these things, I wouldn’t put a new pair to my ears until I had put two weeks of audio through it inside a closet.
If you are talking about burn-in then honestly it’s total bs. Headphone or speakers don’t require burning to unlock their potential. Its more of marketing gimmick to sell you bad pair of audio gear. If it sounds bad at first point nothing is going to change after running it for a couple of hours or even a week. If you believe it sounds better after a few listening sessions then its basically your brain adapting to the new sound so every time you listen it sounds better and more natural.
But if you speaking from emotional or sentimental point of view, I get that. Its had to accept a replacement which you have daily driving for 20 years. You ears have adjusted to that sound. The old was better inspite of the new one being better in every sense. Thats exactly what nostalgia is 
Yep, burn-in!
Just another reason why I decided being an audiophile is not worth shortening my lifespan for.
Some would say it’s not real, others would swear by it, a group who would say it’s all in your head and yet another group would say it’s more about pad wear.
There’s just way too many subjective variables.
Of course now @Crazy_Eddy has the perfect chance to compare the frequency response curve of his unit with a brand new one, haha.
I’ve done it in the past with a couple of koss headphones, the newer stuff just was more crisp. Five year old porta pros or ur40’s just didn’t sound the same as new ones.
My personal theory is that burn-in was real in the olden days but manufacturing QC became better at some point in the last 15 years and negated the entire concept.
Its been a myth since the birth of time -
You can go with either of the following:
OR
Did you do it after replacing the old earcups or pads with new ones? That could be a reason for the difference between the variations. The older pads have oil and dust absorbed which acts like dampener making the sound a bit mushy when compared to fresh new ones.
Indeed being an audiophile is a tough job, the market is full of snake oils. The worst part is there are groups which die heartedly believe in these snake oils so it’s hard to cut the clutter and focus on things that truly matters.
I had relatives ask for my 2003 ur40 and 2008 portapro on different occasions but after a few years of owning each. Both times, I bought replacements within a week and I felt the sound was different and switched them back with my originals and preferred them over the newer ones.
Could definitely be pad wear because I never experienced it with ear buds.
Artsy people I knew in the early 2000s used to swear the grado sr60s changed over time but then they were artsy people, a sneeze probably reconfigured their worldview.
The driver burn-in thing is very dependent on what kind of driver the headphones have, and it’s largely been debunked.
Pads however do affect the sound substantially and the foam inside the pads do wear out, thus changing the sound over the course of the pad, till a point anyways. This has been proven with actual measurements time and time again rather than just words and snake oil. Does that mean everyone can hear the difference? That’s up for debate.
I thought the same way about flac vs compressed mp3. Thought there’s probably no audible difference because I never could hear any. Until I got better gear, and now depending on the track complexity, the difference can be fairly substantial.
Though most people still can’t tell the difference.
And for that you’re very wise.
I personally found the 599SE kind of shouty and a bit boomy on some tracks. If you’re looking for the sennheiser signature sound, which is just the mids they have honestly, 560s is a solid option.
I really want to see a frequency responsive curve comparison between OP’s new and old headphone if both are Sennheisers.
Since it’s a relative comparison, he doesn’t even need high-end gear. Just any old omnidirectional microphone would do.
You can also do a simple blind test with new gear pre and post burn-in