I picked up a pair of these on a whim in a junk shop the other day, Pioneer SE-205s, for a shade under £3. They're in good nick, comfortable, built like a brick shit house, offer nice isolation and when properly driven have surprisingly good, clear bass response, much better than I'd expect from a set of headphones of their age (somewhere between '74 and '88). Unfortunately, while they're nice enough for classical, folk, jazz and so on, they get muddier as the source gets hotter; not great for anything much modern, and hopeless for metal, breakcore etc.

So I'm wondering, is studiolad still around, or any of the other audioheads that have graced these parts over the years, to offer a bit of advice? They're 70mm drivers (4Ω) so I'm thinking of trying to find a suitable "spare/repair" modern donor pair on ebay, but are there alternatives, like somewhere specialist online where I can just buy decent replacement drivers without them costing more than the project is worth? At ~£2.80 it's not like I'm particularly invested so far, and while I do like how solid the construction is on these, I'm not about to go cannibalising a better working set of headphones for that reason alone.

Ta lads. (I thought this was more /g/ than /beat/ on account of it being a hardware question, but will repost there if requested.)