to simulate an experience closer to listening to music through good speakers in a complementary room space.
NAD Viso HP50 Headphone
- Clean, well balanced sound quality.
- Light weight.
- Crisp, modern design.
- Easy to drive.
- Potential fit issues with larger headed folk.
PSB M4U 4 In-ear Monitor
- Crisp, clean highs and mids with lots of bass.
- Easy, comfortable fit.
- Solid build quality.
- Comes with both silicone and Comply foam ear tips in a few sizes.
- Easy to drive.
So why am I combining two different products in one review? Well, they might not be quite as different as you first might expect, at least when it comes to their overall purpose and goal. Our story begins back in January at CES 2016. I had the distinct pleasure of chatting with Greg Stidsen of NAD and Paul Barton of PSB while visiting the Lenbrook suite. The Lenbrook Group is the umbrella company that oversees both PSB and NAD as well as Bluesound. We were discussing some upcoming products and technology that both gentlemen were working on, when Paul asked me if I had a chance to listen to either of the company’s earphone offerings.
NAD Viso HP50 Headphone
Dynamic Over-the-Ear-Headphones, Closed Back
40 millimeters in diameter
Manufacturer Freq. Response:
20Hz – 20kHz, +/-1.5dB, -3dB at 15Hz
Black, white, red
47-inch, iOS-compatible cord with inline microphone and remote control with 3.5mm jacks, 47-inch basic ribbon cord with 3.5mm jacks, 3.5mm to 6.35mm adaptor, twin 3.5mm airline adaptor, accessory pouch, carry case
NAD, VISO, HP50, Headphones, Over-the-Ear, Closed Back, RoomFeel
PSB M4U 4 In-ear Monitor
Two-way hybrid dual driver in-ear monitors
Single balanced armature driver for mid and high frequencies, 8mm dynamic driver for low frequencies
Manufacturer Freq. Response:
20Hz – 20kHz, +/-1.5dB, -3dB at 15Hz, -10dB at 10Hz
47-inch, iOS-compatible cord with inline microphone and remote control with 3.5mm jacks, 47-inch basic cord with 3.5mm jacks, 3.5mm to 6.35mm adaptor, twin 3.5mm airline adaptor, carry case, carabiner clip, 3 pairs silicone ear tips (S, M, L), 3 pairs Comply foam ear tips (S, M, L)
PSB, M4U, Earphones, IEM, RoomFeel
When he heard that I hadn’t, both he and Greg suggested I try out both the NAD Viso HP50 headphones and the PSB M4U 4 IEMs to get a good sense of what their “RoomFeel” technology could do with both categories of product. “What’s RoomFeel?” I asked curiously. Paul Barton then enthusiastically launched into a detailed explanation of all things “RoomFeel” while Greg Stidsen politely listened, nodded and chuckled good-naturedly! Suffice it to say that both men feel that this technology is a big enough deal to warrant its use on both their products, with Paul Barton taking the lead on the engineering end.
And while I’ll explain it in more detail later on, “RoomFeel,” in a nutshell, is about recreating the experience of listening to music through good speakers in a good room, through your headphones. The theory being that music is produced, mixed and mastered with the intent of it being played back through speakers. Listening through headphones introduces a number of other variables to playback that are not originally accounted for in music production. Do these two earphone products remedy that situation and make good on the “RoomFeel” concept? Read on and find out!
Beginning with the NAD, the Viso HP50 headphones come packed in a nice sturdy box with modern graphics. Upon unboxing, the first thing you notice are the headphone’s aesthetics. It’s got that minimalist, Scandinavian, IKEA kind of vibe going on about its design. The tapering black leatherette-wrapped headband is a simple, but comfortable affair that transitions to the sleek, squared off, black plastic ear cups. The cups have a fairly limited range of motion in the horizontal plane of about +\- 90 degrees in one direction and a limited amount of vertical pivot.
The ear pads are also covered in a soft leatherette and are meant to completely fit over the ears. These headphones are a closed back design with 40mm dynamic drivers and a 32-ohm impedance, which make them ideal for use with a smart phone or digital audio player (DAP). Smartphone functionality is enhanced with an included, iOS-compatible, flat cable with inline mic and controls. Also included is an additional flat standard cable, the usual array of adaptors for travel and home use and a travel pouch. The headphone cable can also be conveniently connected in either ear-cup depending on what side you prefer to carry your DAP on, which is a nice touch.
The PSB M4U 4 IEMs, in contrast, are fairly conventional in appearance, not that that’s a bad thing. They come equally well packaged with a similar assortment of accessories as the NAD headphones. Physically, they are a low-profile design, constructed from ABS plastic, with detachable cables that are meant to loop up and around the ears.
Technically, they sport a unique dual driver design consisting of a balanced armature driver to handle the upper and mid frequencies while an 8mm dynamic driver takes care of the low end reproduction. All this is controlled with a precision crossover network designed to help the disparate driver types integrate and play nicely with each other. The PSB IEMs also come with an iOS-compatible inline mic/control cord, a carry case and an array of silicone and Comply foam ear tips of various sizes.
The common thread that links these two very different earphone designs together is the genetic secret sauce dubbed “RoomFeel.” Stemming from studies originally conducted at Canada’s National Research Council laboratories to improve the designs and performance of hearing aids, Paul Barton has adapted, developed and further applied that research to consumer audio products. RoomFeel is essentially a tuning methodology, for earphones, that simulates the effect of listening to music through high quality loudspeakers in a complimentary room environment. My layman’s understanding of the process goes something like this. The music we consume is, for the most part, monitored, mixed and mastered using loudspeakers as a control, both in the production and with them being the ultimate playback destination in mind. And since we don’t live in anechoic chambers, the loudspeakers we do play back our music on benefit, in the best of circumstances, with a certain amount of room gain that bolsters their output (usually in the lower end) and helps give us the desired sound we are accustomed to. Even an “ideal” speaker tuned for the flattest possible response, both on and off axis, will benefit from room gain as it will tend to increase the total acoustic power output that the speaker will produce. The caveats, of course, being that you are using good speakers and they are setup properly in a good room. Since head and earphones do not come with reverberant rooms of their own, their sound is more directly dictated by what comes out of the drivers. Different manufacturers will tune their headphone based on whatever criteria they feel they want to meet, whether they’re after a more neutral response, or an increased lower end or an accentuation of the midrange, etc. A headphone with a perfectly flat response sounds good in theory, but in actual practice doesn’t sound all that enjoyable for music. What Paul Barton seems to have done with RoomFeel is that, after much experimentation and measurement, he has developed a response curve for head and in-ear monitors that accounts for what an excellent loudspeaker with excellent on and off axis response would sound (and measure) like in an excellent room while factoring in the resulting loudspeaker power response. Both the NAD and PSB head and ear ware have had their drivers and crossovers tuned to match this response curve which, according to Barton, leads to a more natural listening experience.
Let’s see if he’s right!
For the majority of my testing, I used both the NAD Viso HP50 headphones and the PSB M4U 4 IEMs along with my iPhone 6S+ when on the go. At home they were connected through an OPPO HA-1 DAC/Headphone amp () using the supplied cables and adapter in all cases.
Beginning with the NAD headphones I found their styling to be a bit of a refreshing departure from the norm. While not necessarily my style, they are a good looking and well thought out design. The available, and convenient, cable connection in either ear-cup is a particular piece of design brilliance worth noting. Let’s just say that if you like wearing black turtlenecks, wear horned rim glasses, shop at IKEA, drive a SAAB and live and breathe all things Apple, this modern looking set of cans will be right up your alley! Even if don’t do any of those things however, you will undoubtedly look sharp sporting this headset the next time you are out and about. The headphones themselves, while feeling admirably light in hand, appear solid and well-constructed. The materials used all seemed durable, of good quality and gave me no wear issues during my review. When it came down to fit, it took me a little more trial and error than usual with a set of headphones to get just the right seal and seating around my ears and on my head. The ear-pads fit just barely around my ears and due to limited horizontal movement of the ear-cups, I found it hard to get a good seal around the back of my ears. This had the effect of destabilizing the imaging when I turned my head. However, once I got just the right amount of extension on the head band though, the seal was good and the sound remained consistent. It all had to remain just so for me to get a repeatable good fit. If I had to pack up the headphones for travel, I would have to hunt for a little bit to get the fit dialed back in. I must admit to having a fat head though, so this might not be such an issue for more, shall we say, “modestly melon-ed” folk! The clamping force exerted by these headphones was comparatively moderate, perhaps a touch more than I’d like. I could easily wear them for 2-3 hours before needing a break. Having them on all night though would be a little tiring.
From a sonic standpoint I found the Viso HP50 to be a delight to listen to, all things considered. They sounded very clean from top to bottom and they also sounded big. Not diffuse like some open backed cans, but big. They had a bigger soundstage than the 40mm drivers and their overall size would have led me to believe. High frequencies had a nice neutrality to them. There were no cases where cymbals or horns sounded overly sharp or cringe worthy. Upper register piano notes had a lovely crisp ring to their sound. Vocals sounded natural and not too forward or over accentuated. Some closed back headphones I’ve reviewed have had a certain level of darkness or fullness to their sound in the lower midrange to upper bass region making some songs sound thick and a little cloudy. The NADs have none of that. Very, very clean sounding is the thought I kept coming back to whenever I listened the Viso HP50s. And then we get to the bass. The NAD headphones put out an impressive level of bass for their size. In all cases from stand up and electric bass to synthesized and electronic, the Viso HP50s had tight and potent bass reproduction with nary a hint of bloat or overhang. The bass also felt like it always had a good deal of power behind it. Not that it ever rattled my skull or anything but, when required, you felt it as well as heard it. Indeed, in many cases, listening to the NAD headphones did make me feel like I was listening to my studio speaker rig in some measure. The size of the sound was just bigger.
In terms of tonality, I don’t think I could have expected any better at this level. The NADs are about as balanced and enjoyable to listen to as anything else in this price range and, in some cases, more so. I think these could easily be my go to headphones if I didn’t have the fit issues that I mentioned earlier. When it comes to comfort, the OPPO PM-3 are still the king of the hill for me in terms of closed back headphones. The Blue Lola come in a close second. I have worn both the OPPO and the Lola when working all night long and my head and ears felt none the worse for wear when I took them off in the morning. I could not do that with the NADs. Again, for smaller-headed persons, my fit issues may be a moot point so try them for yourself if you can. With all that being said however, for shorter listening stints, I would choose the NADs without question.
Moving to the PSB M4U 4 in ear monitors, they also feel suitably light weight but are undeniably well built. The ABS outer housing feels durable and should be resistant to daily abuse. As with all earbuds and IEMs, a good deal of experimentation is needed to get the right ear-tip combination that will ensure a proper seal when fitted. In this particular case, the large size Comply foam ear-tips proved the best choice for me to achieve the best seal and sound. The PSBs sounded too thin for my liking when paired with any of the silicone ear-tip options. With ear-tips selected, the PSB IEMs were easy to insert and created an excellent seal, blocking out most outside sounds. Looping the cables over the tops of my ears made sure everything stayed put. Similar, to the NADs, the first thing I noticed about these PSB IEMs was the clarity of the overall sound. Second thing I noticed was the size of the soundstage and, sure enough, it was big. The PSBs definitely had the sensation that I was listening to something other than headphones. Their upper end airiness and refinement is particularly noteworthy with crystal clear highs that sounded grain-free. I could see that some who prefer a more relaxed sounding top end might find the high frequencies on these IEMs a little too forward, but I wouldn’t be one of them. Both male and female vocals seemed properly placed and were presented with plenty of body while still remaining clear and in balance. The midrange, in fact, sounds rather lovely. It comes across as smooth and balanced, like a good pair of speakers, and does make some other earbuds and IEMs I’ve tried sound a little thin or laid back in this area by comparison. Throughout my listening, I couldn’t discern any particular darkness or thick sound in the lower mid to upper bass region. And speaking of bass, these little PSBs sure have the goods in that department, almost more so than the NADs. The M4U 4’s bass was powerful, verging on almost too much for acoustic bass. On rock music and electronica though, I think it’s a safe bet that most people will be pleased with the bass levels. It didn’t sound sloppy or boomy at all, but what was there was certainly there in abundance. The Comply ear tips may have a little something to do with the bass levels as it’s been my experience that using them tends to accentuate the bass level on earbuds to varying degrees.
From a comfort standpoint, I had no complaints with the PSB M4U 4. They were very comfortable to wear for hours on end and totally easy to live with for work and travel. Insertion and fit was unfussy and a good seal was easily repeatable. I could happily live with these for daily use without reservation.
As my review time with these earphones drew to a close, and I reflected on my experience with both the products and the concept behind them, there was one thought that kept popping back into my mind. That is, how much I would like to see the RoomFeel system applied in a no-holds barred over the ear headphone design. A high end and cutting edge statement that could compete against the likes of HiFiMAN, AKG, Sennheiser and Beyerdynamic’s top offerings. While surely not the most practical of products, it could be glorious fun to listen to!
Two Sides of the Same Coin. That’s How I Would Describe the Nad Viso Hp50 and the PSB M4U 4 EARPHONES.
- Big, wide sound stage.
- Clean, balanced sound.
- Unique styling.
- Left or right side cable connection is genius!
- Wider, thicker ear-pads for a more comfortable fit.
- Wider range of horizontal motion for the ear-cups.
- A touch less clamping force.
PSB M4U 4 In-ear Monitor
- Big, wide sound stage.
- Clean mids and highs with gobs of bass.
- Very comfortable.
- Instead of a carabiner accessory, maybe include a few extra pairs of Comply ear-tips.
Two sides of the same coin. That’s how I would describe the NAD Viso HP50 and The PSB M4U 4 earphones. Each product provides a big clear and balanced sound that does, in many ways, mimic the sound of good speakers in a good room. An enviable trait to have in a pair of sub $300.00 earphones to be sure. There is definitely something to be said about the RoomFeel tuning methodology used on both these products. It’s certainly more than just a simple tuning curve or target. While each product still retains their own particular sonic characteristics, RoomFeel does imbue a larger and more potent soundstage than what might otherwise be the case. It also bears repeating that the sense of clarity that each of these products conveyed during listening was indeed impressive in this price range. Both those characteristics, combined, helped give me the sense that I was listening to something bigger than just a set of earphones. Well done Mr. Barton and company!