If you're into fixing things up,--and since this is a Bottlehead forum, I imagine you are!--the 600-ohm AKG K240 Monitor and K240 Sextett are fantastic and can often be found on auction sites for $50-100. You'd likely just have to clean out the rotted foam and maybe replace the headband-adjustment elastics. And then replacing the earpads with Brainwavz hybrid oval or hybrid Kraken really elevates these old studio cans into something special IMO. Comes to $80-130 total.
I have the K240 Sextetts w/ Brainwavz hybrid oval pads, and my brother has the K240 Monitors w/ Brainwavz pleather oval pads, and he also has the Senn HD-600. We've done many listening tests thru the Crack and agree that the three cans are pretty similar, especially with midrange presence. Where the AKGs excel is in how they sound more like we're listening in a live space, with the Sextett a bit better than the Monitor regardless of which pads we use. The Senn's pull out a little more detail, but the midrange realism goes to AKG.
If you want a more obviously different sound than your Senns, the Beyer DT 770 Pro 250-ohm ($159 new on some auction sites) will give more laid-back mids, brighter treble, and fantastic bass slam. Hope you find something great! Cheers!
Lol Paul, he said under 500 and you're suggesting cans over $1K!! xD
