My colleague owns a pair of HD 580. Their sound is very versatile, bass and highs are extended perfectly. Despite that, extreme ends never flood the mids. Whatever you listen to, they will not let you down. So I bought one too. A huge disappointment. One word: veil. "WTF?", I thought. The same headphones model, sound totally different. The answer is: there are 4 versions of HD 580. Germany made, early Ireland made, mid Ireland made, late Ireland made with bright driver screen. I probably bought the worst one (mid Ireland). My colleague has early Ireland version. I read some headfi opinions about HD 580 line. Apparently the oldest one (made in Germany) were the best sounding. So I started to look for them and never succeeded. I gave a try some other old models: HD 545, HD 540 and landed here with my HD 540. HD 545 are the brightest sounding headphones I've ever heard. It's pleasant to listen too as long as you don't miss the bass and good balance. HD 540 blew my mind. The highs are unbeatable, never heard better. The timbre of treble and mids is so relaxing and sweet pure joy. The rsolution is very satisfying. Bass is good. Not as good as HD 580 tough, not as extended as I'd like it to be. But it's ok. The texture of bass is well recognizable and when a song is based on bass, you can feel it does. Generally I prefer HD 540 to my colleague's HD 580. The comfort is near HD 580, not easy to compare beacause the pads are not as fresh. Both are good for long listening. I love the look. Very subtle and noble. They survived almost 30 years and are in very good condition. I thought HD 580 are light. I was wrong, HD 540 seem even ~30% lighter. I am ready to buy HD 250 (or HD 430) pads and a cable replacement, but there's no need. I compared them also with AKG K701. The main differences: bass is very similar, K701's mids are artificial and too bright, K701's treble is dry, and unpleasant, scene is wide but undifferentiated. HD 540 has mids on the right place and uncanny timbre, scene - sometimes you hear voices near, sometimes they are further, you can notice the movement of them. I hope they will serve me well for years.
Purchased used from a friend. I shoe-gooed the pads to keep them going, but otherwise... I have AKG 701 and Yamaha yh-100 and I keep going back to these. They are as good as my other cans in many ways, but just not as demanding physically. I mean they are light and comfortable like a glove. The AKGs leave huge dimples in my bald head, where these don't. They need power, which I can hardly supply with my equipment. But they are a true hifi experience every time I use them and you hear everything like it's in your head. I'm having a hard time finding pads though.