**HD800 SDR SOLD** I'm considering selling my HD800 with super dupont resonator (SDR) mod installed, along with my ECP Black Diamond headphone amp. Both are in excellent cosmetic and working condition. I purchased them both used recently from reputable head-fiers a few weeks ago. This HD800 was modded by the previous owner and contains no nicks, scratches or blemishes that I have observed on the cups or headband. If desired, I can share the frequency response graph for this particular modded unit provided to me by the previous owner. The HD800 comes with original packaging with like new Periapt cable terminated to 1/4" ($100 value). Please note that stock cable is not included! The ECP Black Diamond amp also shows minimal signs of use with only a few very minor surface scratches present on the tops of the transformers that are barely noticeable. The amp comes with the stock power cable and contains an upgraded power supply installed by ECP Audio. Why am I listing these items together? Because the general consensus is that this amp is a perfect match for the HD800, and I tend to agree. This amp has a very euphoric, somewhat forward midrange, intimate presentation and organic tonality that helps bring out the best in the HD800. I am letting these go because after much deliberation, I have decided to slim down my desktop set-up in favor of portable gear. As much as I try, I just can't find the time to listen enough at home to make it worthwhile to keep these. So instead, I would like to stick with a more budget friendly home set-up and put more funds into my portable rig, which gets far more use. Pricing: - HD800 SDR with Periapt Cable = $750 - ECP Black Diamond Amp = $650 - Package Deal (HD800 + Amp) = $1325 Price includes shipping within CONUS with insurance, tracking and PayPal fees. For a 3% discount, feel free to pay via friends and family transaction (I have excellent feedback, so buy with confidence!). Please let me know if you have any questions, and as always, thanks for looking!