I heard of bootleg DVDs and CDs, fake watches and parfumes, but I never knew that a market existed for fake headphones. I found this little page at HeadphoneDeals.com, that explains some characteristics of fake headphones. It’s quite useful if you’re an eBay-user, because it seems that that’s the place where they hang out most. I would always try to buy second-hand through the Head-Fi secondhand forum first though.

Doug