I’ve got those Sony MDR 7506, I think they might be the brightest sounding headphones that ever were. Brighter than my Grados even. You are going to need to carefully select the amp for those phones. I’d suggest something that has a warm sound signature.
And just so you can get a different flavor, I suggest getting a pair of Koss Porta Pro headphones. A warm sound but still good detail. Don’t be thrown by the looks, they’ve been in production since 1984 for a reason. At 30 bucks or so, you’ll thank me.