From one seller and it's like $20 a connector. I usually spend less on an entire Paracord than I would on that one connector.

Big fan of diy cables, use them on everything except my Sennheiser because of the stupid connector they use.

It seems we have the same headphones and very similar tastes in music OP! I largely agree with your review but have a few notes I would want to add for anyone interested in an HD58X. I listen to mine with a DIY Objective 2 AMP so my experience may be slightly different from OPs.

1. The included cable is trash, I have had a ton of problems with mine. It's far too long for my taste, made of poor-quality rubber, and I constantly have to fiddle with it to get it working properly. This wouldn't be a huge issue except that Sennheiser uses proprietary headphone connectors so making a DIY cable as I usually do is quite difficult.

2. OP describes the sound stage as "OK" while I would go as far as saying it's downright underwhelming. The soundstage is barely wider than most closed-back headphones I have tried, and as someone who often struggles to find a quiet listening environment, I often reach for my Sivga or Sony headphones which have only a slightly smaller soundstage and the benefits of being closed-back.

Still good headphones, probably the best-sounding pair I own especially in the imaging department. OP has very much made me want to purchase a DAC instead of using what is built into my PC with their remarks on KDA and Itzy, two of my personal favorites.