Dumbleroar-Leather pads should last a virtual lifetime, I see know need to replace them
radioscott1, I would doubt that there is any significant difference between S-Logic and S-Logic plus beyond marketing, however the Sig Pro does a fine job of imaging and soundstage presentation. I haven't heard the 580s, however the Sig Pro is in another class to the Pro550 and DJ1 Pro and Pro900 that I have owned.
The Signature Pro is very well balanced, almost neutral in presentation, with an ability to render instruments and vocals in a convincing way. The most natural sounding of the Ultrasone line-up I have heard and amongst the most neutral/natural sounding headphones regardless of type. The Sig Pro is a dynamic
headphone, with energy to its sound signature, music sounds intense and alive, very punchy, crisp, clean, and detailed. Drums have a “thwack” and "thump" to them, hi-hats crash, cymbals "clank and ping" when they should (not just a one note tish), and guitars are full bodied from the twang of the strings, slide of the fingers, to the resonance of the wood. Imaging and instrument separation is superb, never congested or blended, good positional sound-stage, not overly airy but not closed and claustrophobic in any way. This detailed and lively sound helps the Sig Pro achieve the balance between being quite neutral but also being a fun engaging headphone. The Sig Pro does benefit from home source components, however it performs and outperforms from a humble DAP. A great all-rounder, certainly one of the best closed
headphones available and in my opinion clearly in the same league as the top tier open headphones of today, and King of the portables.