Tentatively putting this up as I'm thinking about thinning the herd. Those who remember seeing my nutty trading spree (linky), I think I'm finally settling and figuring out what kind of sound I'm looking for. These two sound great, but I'm finding they just aren't my cup of tea as I find myself leaning towards my other toys first, and I really can't justify having two tube amps either. The AKG K340s are an electrostatic/dynamic hybrid. I actually have two of these; both the bass heavy (modded: recabled, damped, new grill, new earpads) and bass light version (stock, still waiting for it to arrive in the mail). They have a sound signature which is rather difficult to describe: an incredibly crisp high end, and a warm bubbly low end. Here are the specs: Transducer: Electrostatic-Dynamic Hybrid Type: Circumaural, Semi-open Frequency Response: 16 - 25,000 Hz Impedance: 400 Ω Sensitivity: 94 dB / mW Connector: 1/4" Weight: 380 g ( Without Cord ) They are beastly hard to drive. The more power you feed them, the better they sound. Which brings us to... The G&W T2.6f tube hybrid. This is the only amp I have which (in my opinion) can properly drive the K340s and my orthos (and I traded the orthos already). It's got a nice clean industrial look to it, and puts out gobs and gobs of power. Not well known in North America, but well regarded on the other side of the ocean. Overall sound is on the brighter side for tubes though it maintains a tight and solid deep end with a lush midrange, and it runs surprisingly cool no doubt thanks to the giant heat sink across the top. Also comes with some upgraded Tesla E88CC tubes. Reportedly this amp was designed with Sennheisers in mind. I have the HD580 and it does indeed match very well. I find this amp does the best with current hungry cans. There is a preamp output, which (from my very brief testing) offers a warmer sound than the headphone output. Here are the specs: Input sensitivity: 350mV. Output：2×1000mW(RMS). THD：0.01%(50W，8Ω，1KHz). S/N: 98.8dB. Frequency response: 6Hz～78KHz(-3dB). Supply voltage: 110~120V 70mm double-gold-plated PCB, WIMA, ERO pacitors. Double-layer stainless steel housing, matt aluminium front & back panels. Alps 2 x 100K(A) blue volume. Russian Electro Hamonix 6922EH tubes. Hitachi power MOSFET 2SK214/2SJ77. Iron-cored inductor with ruby electrolytic capacitors as π type filter. 20-second mute protective function. I would prefer to keep the K340 and G&W together as a combo unless I happen to find two people interested in each separately. Everything is in pristine condition. Non-smoking, non-pet home. I'm slightly ocd about cleanliness, so everything has been babied and kept fresh as any proud headfier would. I've also got a Yamaha YH-3 ortho that pairs quite well with the G&W as well, if anyone's interested in packaging that together as well. Get your stat and ortho fix all in one shot! Open to trades as well. Looking for a nice solid state amp, or a Senn HD25-1, some other high end can or amp, or anything interesting really. Shoot me offers.