Thinking of making room for other things to come. Only shipping to the US at this time. No trades. Smoke-less and pet-less home.---------------------------------Basically, I bought DT880 600 ohm drivers from Beyerdynamic and transplanted it into a chassis of a vintage headphone. The chassis is of a Peerless PMB80 which is an old orthodynamic/planar magnetic headphone that didn't sound too particularly good below 100-200 Hz. The DT880 600 ohm drivers are just better. I still have the original drivers but it is pretty much impossible to put them back on - IIRC, they essentially suspend in mid-air in the chassis only kept in place by the foam that it had but now has crumbled. I will still include the orthodynamic drivers. The right side seems to have had some sort of repair done that doesn't allow for any horizontal swivel. The left side does swivel. They still fit and seal around my head surprisingly well. The top of the headband started to develop some cracks in which I put some electrical tape around it to prevent it from breaking. The pads are modern DT880/DT990 pads and they still look to be in very good condition since I nearly never use them.As for sound, they sound like a DT880 with less mid-bass and treble. You can extract the drivers for spares though just be careful and quick when desoldering them. The little wires damage very easily - I've destroyed around 4-5 Beyerdynamic drivers by lingering a bit too long.Measured on a MiniDSP EARS. HPN compensation.---------------------------------This was an experimental mod that I was in too deep in. Basically CAL! drivers in a vintage Fostex T20 chassis (the very first, 1970s one). They sound surprisingly good. Original T20 drivers are busted. Condition is ok. Missing one of the badges on the adjustment yoke though it's merely a cosmetic issue.The pads are a bit old and dirty but they do good things in terms of frequency response. The cable is the one used on the CAL!You can just extract the drivers and use them as spares or for other chassis. Should be pretty easy to find being 40mm drivers - blu-tack will be your best friend.Measured on a MiniDSP EARS. HPN compensation.---------------------------------I bought these again to replicate the mod that I did to a pair a few years back. Unfortunately, I don't quite remember the exact materials I used and they don't sound quite as good as they could be. They still sound pretty nice overall. One side of the headband has a broken plastic bit where the threads are for the screw to connect - I put some blu-tack there to sort of adhere that side of the headband on. You can pretty much remove the cardboard headband and just slap a ZMF Pilot pad on top since the earcups adjust vertically rather than the headband.I couldn't get these to seal well on the MiniDSP EARS to measure them.