NAD's first entry into the very busy headphone market is the Viso HP50 headphone, a full-size but lightweight (9.6 ounces) over-the-ear model. When NAD decided to introduce its first headphone, the company turned to Paul Barton, founder and chief designer for NAD's partner company PSB to design it. Paul Barton has long been known for two things. First, he's known for his comprehensive approach to audio engineering, conducting extensive R&D to craft his designs. Second, Paul is renowned for designing value-priced high-performance loudspeakers. The Viso HP50 headphones follow both of these longstanding approaches.

Paul has long collaborated with the National Research Council (NRC) of Canada to study the relationship between the measurement of music and the subjective evaluation of music, or measuring versus listening. He took the same approach in designing both the NAD Viso HP50 headphones and his own company's PSB M4U 1 headphones, albeit with a slightly different target sound for each. Paul points out that one of the key differences between listening to music through headphones and listening to music through a pair of loudspeakers is that the effect the room has on the sound is missing with headphones. Since most music is recorded and mastered to be played back on a pair of loudspeakers in a room, Paul created an innovative headphone technology he has coined "RoomFeel" that's intended to add back the effect the room has on music, more closely matching the sound's timbre and balance to what's heard when listening to a pair of loudspeakers.

On top of that, he set an attainable suggested retail price of $299 (current street price of $250) for the Viso HP50. While admittedly that's not inexpensive, it's certainly reasonable compared with the price of most audiophile-grade headphones today.

So what do you get for your money with these NAD headphones? Well, the Viso HP50 is a sealed design, with elliptically shaped, soft leather ear pads that I found to provide a very effective seal while still remaining very comfortable. The pivoting ear cups help to provide that tight seal for a variety of head sizes and shapes. The headphones also fold flat for easy storage and transport in the included padded vinyl zipper case. The outer panels of the ear cups also come in a choice of three gloss colors: black, red, or white (shown here). The headband is narrower than most other headphones but is sufficiently padded to be comfortable.

There are two included 48-inch headphone cables in a ribbon style to prevent tangling: one with an Apple controller three-button remote with microphone for smartphone control and one standard cable. For listener convenience, the cables can be connected to either the right or left ear cup. Both cable types are terminated with right-angle 3.5mm plugs for connection to devices such as a DAP (Digital Audio Player), portable headphone amp, smartphone, iPod, or iPad. Also included in the box are 3.5mm-to-0.25-inch and airplane adapters, providing additional source connection capability. To top it off, there is also a small pouch included to keep track of the extra cable and adapters.

The Viso HP50's 32-ohm impedance and 100-dB sensitivity mean that it should be capable of outputting plenty of volume when paired with a smartphone or DAP. And in fact, from the first time I connected the Viso HP50 to my Astell & Kern AK240 DAP and hit play, it was obvious that these efficient headphones could play more loudly that anyone would ever need or desire. I had similar results with my iPhone 6 Plus. I did briefly test the Viso HP50 headphones with a headphone amp to see if there were sonic benefits. While I heard a slight improvement in bass dynamics, soundstage width, and imaging, it was less of an improvement than I've experienced with other less-efficient headphones. So, use a headphone amp if you want, but there is no need for one.

I used my AK240 and iPhone for most of the evaluation, listening to my own ripped 16/44.1 files, Tidal streamed content, 24/96 and 24/192 files from HDTracks, and even MP3 files streamed from Pandora. I even took the Viso HP50 on a two-week trip to Alaska to see just how well they play while on the move. I listened to these headphones on a plane, a train, and a cruise ship. The Viso HP50 did a good job of blocking out external noises except for the lowest frequencies. I compared the effectiveness of the Viso HP50's passive isolation to that of my Shure 535SE in-ear monitors that have been my long-term travel headphones. The drone of jet engines came through to a greater degree with the Viso HP50 than with the Shure IEMs. Not a big surprise since the IEMs fit snugly inside the ear canal to create their seal. Still, the Viso HP50 did a better job at isolating noise than similar designs, proving to be quite listenable. The Viso HP50 had a silent background on the train and cruise ship, with no external noise detected.

The sonic character of these headphones is one with plenty of bass punch when the music calls for it, but they're also balanced through the midrange and have good clarity and tonal precision in the upper ranges. There's a bit more presence to vocals and airiness to the music. Overall, these headphones just seem to have a pleasing, balanced response that's enjoyable no matter the genre.

High Points
• The NAD Viso HP50's sealed design provides effective isolation from environmental noise while also managing to sound more like you're listening to music from loudspeakers in a room, with a more natural, open, and three-dimensional sound.
• The NAD Viso HP50 headphones' slightly relaxed top end, paired with their lightweight, comfortable fit, means that users are able to listen for hours on end without the usual listener fatigue or discomfort found with many other headphones.
• The Viso HP50 can be paired with a smartphone or portable DAP without the need for a separate headphone amplifier to achieve adequate listening levels.

Low Points
• The gloss finish of the ear cups picks up fingerprints easily.

Comparison and Competition
There are many competitors at similar price points, including the PSB M4U 1, the Audio Technica ATH-MSR7 (read Adrienne Maxwell's recent review here), and Monster's DNA Pro 2.0 (review coming soon). I haven't listened to the PSB or Audio Technica headphones enough to form an opinion, but the Monster headphones provide more bass boost compared with the Viso HP50 for a slightly darker sound.

Conclusion
In the NAD Viso HP50, I've found a closed-back, audiophile-grade headphone for everyday use that sounds more like an open-back design and has a more reasonable price than typical audiophile headphones. The Viso HP50's balanced sonic presentation makes it pleasing to listen to with any music genre, plus these headphones are comfortable to wear and easy to drive. I couldn't ask for more.

Additional Resources
• Check out our Headphones category page to read similar reviews.
• NAD Expands Range of Headphones with VISO HP30 at HomeTheaterReview.com.
• Visit the NAD website for more product information.