I have listened to and owned some great headphones in my time and I recently purchased a pair on NAD Viso HP50's on the recommendation of Tyll Hertsens great "I Love These Headphones" review on the product.
When I first got them home, I opened the package and thought they were not the nicest looking cans. I also thought the build quality was a little on the cheap side. I plugged them into my iPod and was thrown back right away at what I was hearing. It's a very well balanced tone between the low and high end. At this point I would say these headphone are really really good. The next morning I went to listen to them again and found that I lost about 66% volume gain on the headphones. I took them back to the shop and they said they have never seen this issue before, they exchanged them for a brand new pair.
I thought it might be fun to hook them up to my Cypher Labs Solo and Blackbird SR71 headphone amp. As soon as I pressed play, I could not believe what I was hearing out of a pair of $300.00 headphones. I immedietly started to wonder why on earth I've been paying THOUSANDS of dollars for a pair of headphones that are in the same league. I'm not saying they are the best headphone I've ever heard, but I just can't believe the quality of sound to price. The price of these headphones give me faith that it is possible to make a high end headphone for little money. I also think that the sound difference between these headphones and my Audeze LCD2's make the LCD2's not as great as they should be for the $1000.00 I paid for them. In other words, if NAD can do what they are doing and sell it for $300, I expect 3x's the headphone for $1000.00. I would also expect a 17x improvement in sound when listening to a $5000.00 headphone and at this point in time I have not found this to be true.
I started getting worried about this a few years ago when companies started charging $1500+ for a pair of headphones that I thought were just okay.
In regards to the HP50's I'm not crazy about the build quality, I had a defective first pair, I have an issue with the cable being to short (this could easily be replaced with a better and longer cable), but over all I have to say these headphones are the best thing I've ever heard for $300.00 ever!!.
More importantly I wanted to say "Thank You" to NAD for bringing the price bar back down to where I think it should be. We are seeing $5000.00 headphones, $2500.00 music players, $10,000.00 headphone/amp combos etc. It's really nice to know that there still are a few companies out there (Like Schitt and NAD), who feel that they don't need to make a 5,000% profit margin on every single item they sell.
Just thought I'd share these thoughts