A not-exhaustive* guide for helping listeners get the best synergy for the HD800** Note: This will be geared toward the HD800S since the OG HD800 is getting hard to find. HD800 is slightly different from the HD800 (which I still prefer with the Sandevistan mod). 2021 Edition here 2017 Edition here BACKGROUND - WHERE I AM COMING FROM I only like the HD800S under certain conditions. The frequency response of the HD800S, despite the Armin Zola resonator (that lessens the 6kHz peak) is still bit too screwy for my tastes. I find that EQ doesn’t work well for the HD800S because its screwy frequency response is caused by super early reflections from how the driver is suspended and angled in front of the ear and by the large ribs and mounting structures of the cups. The treble is hot, the mids are recessed, and the lows are a bit cloudy (the HD800S took a slight step back in the lows), especially compared to the awesome low-distortion planars available today. This guide should still be applicable to those with the OG HD800 with mods (BTA, Sandevistan, Superdupont, etc.) As far as amping, tube amps are recommended, but solid-state amps are definitely getting there. What we are looking for is one or more of the following traits: Wetness or bloom (the HD800S can be on the dry side) Smooth highs (to counter the hot and grainy HD800S highs) Commits few sins of omission, capable of rendering microdynamics and microdynamics (the HD800S is super resolving, subpar gear and subpar recordings won't make the HD800S any more special than lesser headphones) Capable of slam (the HD800S can hit like a truck with the right gear) Also, tube amps which are overly warm, syrupy, slow, or romantic (cathode follower OTL designs, OPT with cheap output transformers, Chi-Fi push-pull cathode bias, etc.) will not be mentioned. They do cure the HD800S dry sound, but at too high of a price in terms of clarity, transient response, microdetail, microdynamics, etc. Personally, I think you are much better off with an HD650 and LCD-2 with a very technically and musically capable amp. If you like the romantic smoothed-over-to-shit kind of sound, best to seek advice somewhere else. Trying to make the HD800S into sounding like an LCD-2 is plain wrong. It's like trying to convert someone who is gay into being straight. One thing I've noticed is that amps with output impedance from 2 to 20 tend to work well for the HD800S***. There will always be exceptions of course ADDITIONAL CONTEXT: https://www.superbestaudiofriends.o...-hd800s-2023-edition.13859/page-4#post-417687 *The reason why this list is not exhaustive is that we HAVE NOT heard every amp. Conceivably there are other amps that work very well here. **This list is a work-in-progress and will be updated to reflect this **One trick with cheap solid-state amps that may sound a bit too lean or dry is to add a small resistor, 2 to 20 ohms in series from the headphone output.