This is expensive. But I'll buy it anyway.
I agree that this should be on the box, by default.
And I'm still looking for a decent case to store the phones too, they deserve that too.
I have used the "5X8SHORTCABLE" that is the subject of this post, now available from Sennheiser for $13.47. After a few months, it became intermittent, requiring me to move the plastic plug that goes into my left earpiece to restore sound in one of the two sides of my HD 598 headphones.
For a while, I thought the problem was in the jack of the HD 598 headphone and was becoming resigned to having to buy a replacement pair of headphones. On a lark, I went back to the original 10' cable that came with the headphones to find there was no problem with ITS connection, indicating that the problem was in the cable.
Time to buy a new cable.
I found the PERFECT cable on eBay, called "Replacement cable with Remote Mic connect iphone to Sennheiser HD598 HD558 HD518." Price is $16.80. Here: http://www.ebay.com/itm/261280639444?var=560224159548&ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649
I received it and started using it... FABULOUS. It adds the 3-button remote that controls volume, pause, and skip/repeat of songs of the typical iPhone inline remote.
Furthermore, its ends are METAL not plastic.
A great deal that will allow you to take your Sennheiser HD 598 headphones out and about, driven by your iPhone, and putting all those BEATSniks to shame!
You sound unlucky.
Well, we'll see how it goes for me. I bought two cables, one for my Momentum On-ear and one for my K545 to replace the little strings that they originally came with. I think manufacturing tolerances might not be as tight for this cable as the stock HD598 cable fits my Momentum easily and locks firmly but this replacement cable, both of them, fit my Momentum very tight and cannot be turned in order to lock, but at least insertion is proper and the tightness secures the cable anyway, lol. I should have gotten a third one, reduced the 2.5mm plug body's outer circumference slightly with my solder iron or fine sandpaper, then it would fit my HD8 DJ. I knew ahead of time but when ordering I slipped my mind.