I am very interested to know where you buy your audiphile headphones new/used from well for me the best websites i found is Reverb.com , scan.co.uk for uk residents , thomann.de, drop.com you could great deals on ebay sometimes and plz do not mention amazon Tell me what is yours? off-topic these are great deals on
hd 600: Sennheiser HD 600 (2019 Edition) + Case and Headphone Holder | Reverb , DT1990 pro:Beyerdynamic DT1990 PRO 250 Ohm | Reverb ,Akg k361 https://www.scan.co.uk/products/bmo-akg-k361-over-ear-closed-back-studio-headphones-black?utm_source=google&utm_medium=cpc&utm_campaign=feed_clicks&utm_content=surfaces_across_google&gclid=CjwKCAjw9qiTBhBbEiwAp-kb ,
FiiO k9:FiiO K9 Pro Desktop Bluetooth Amp & DAC. Free UK Postage. | eBay
As far as new (or like new) I wouldnt say there is a single website that is “the best”, for example “The site who shall not be named” (Amazon) might be pricier at times but it has worldwide shipping with free/low rates along with a fairly robust return that is a great option for some (practically if you are outside the US & EU).
You can also find great deals on sites like Adorama, Linsoul, Audio46, hell even Aliexpress has really great deals if you are willing to wait. if you want to find the best deal the Deals thread is a good place to start, also checking a varity of websites is alway.
Ebay is a bit of a wildcard, i wouldnt advise it for high ticket items (from what i remember their buyer protection is only up to 500$)
For just general source equipment including headphones I use the below:
- Audio Mart | https://www.usaudiomart.com/ or https://www.canuckaudiomart.com/ depending on your location
- The Music Room | https://tmraudio.com/
- Audiogon | https://www.audiogon.com/
- This forum and other forums like the HEADPHONE Community, Head-Fi Classifieds, etc.
Other than forum listings you can just use Hifi Shark for https://www.hifishark.com/ which does an aggregated search across multiple websites including the ones I mentioned above.
Some oddballs include Ebay and on extremely rare occasion Goodwill Auction (for the US folk) Home - shopgoodwill.com where I saw an Audeze LCD-1 once.