Pros: Accurate, natural sound filled with great energy and resolve.
Cons: Nothing that comes to mind, but nothing is perfect either; There is always room for improvements.
PSB M4U 1: A New Standard is Born
I am quite sure that many of you, myself included, have started on the seemingly never ending path to finding the perfect set of headphones. Terms such as too bright or too dark, mid-bass hump and recessed midrange, peaky treble and accentuated sibilance, are enough to drive a sane consumer mad. Or at the very least an unnecessary waste of one’s hard earned money. There has simply been no frequency response standard in headphones, until now. In conjunction with their sister company NAD, PSB Speakers has set the new reference standard on how headphones should sound that not only faithfully reproduce the music, but is universally pleasing to all including the most demanding of listener. For a first attempt they sure got it right.
Highly acclaimed for both performance and price, PSB Speakers has been an industry leader in the world of high-end loudspeakers for nearly 40 years. Realizing at an early age that loudspeakers did not sound too great, company founder and chief designer Paul Barton set out to design and build his very own loudspeaker in his family’s woodshop. It wasn’t long before Paul was selling his speaker kits to university students and in 1972 he and his wife Sue formed PSB Speakers. Two years later, with the help of the Canadian NRC (National Research Council), Paul’s psychoacoustic research literally changed the world of loudspeakers forever. His research determined how a loudspeaker’s frequency response curve should sound to faithfully and accurately reproduce the music as intended by the engineers of the recording.
Paul Barton’s on-going research and methods of determination are regularly used by not only PSB, but most high-end loudspeaker manufacturers to this day. Unfortunately, in the world of headphones there is no industry standard. Despite knowing how music is produced and how music is supposed to sound, no manufacturer has developed a transducer headphone with the same acoustic sound signature as the loudspeaker.
“ Nowadays speakers are much more consistent; They aren’t ‘black and white’, ‘day or night’ different, and if they are then they are rejected. So, I think headphones (in 2013) are in about the same state right now that loudspeakers were in back in the 1970’s. Because there is no agreement on what the ideal target response profile for a headphone should be. “
Paul Barton, Hi-Fi+ (Aug. 2013 excerpt)
Growing up in a family consisting of musicians, broadcaster/sound engineers, and amateur DJs, I always had a deep appreciation and understanding of both music and sound. Beyond Elementary School ukulele, my interest was always been in appreciation rather than creation. I was further educated in this self interest after taking courses in both electronics and sound (electro-acousto); There are not many instruments I have have not stuck a mic in or around and sampled it’s waveform. While I believe a listener’s preference in sound is subjective, the science behind it is not. I am someone who, when a guest at someone’s home, takes it upon myself to perfectly calibrate their Home Theatre and HDTV by the time they return with drinks. I am someone who enters a noisy room and hears all the annoying noises that no one else hears. People I know call me first when needing knowledgable advice and opinion when it comes to computers and consumer electronics. I am not swayed by buzzwords, hype, trends, brand recognition, or big numbers on charts; I am the nemesis of the commissioned salesperson. Opinionated as I am, my words are not only objective but honest. I view all criticism as constructive, as long as it is sincere. All equipment in this review was decided upon and purchased by me. No company has sent me any of their products (though I wouldn’t turn them down), and nobody is endorsing me to write this review.
In all honesty, I never had an interest in headphones up until the past two years. To me, headphones were always more of a utilitarian device, used out of necessity. Beyond monitoring and the occasional gaming session, my use of headphones was limited to blocking out the noise of my daily travels. To me, listening to headphones while engaged in either music or movies was less than satisfactory; They simply could not compare to my hi-fi loudspeakers. The problem is not so much that I found headphones to be inadequate, rather I knew that if I wanted sound comparable to a good hi-fi system I would be needing to spend a lot more money than I was willing to. That is, until my work hours shifted to a later start time and I could no longer listen to my hi-fi system; Both my wife and townhouse neighbours would be fast asleep and unappreciative of me blasting my music throughout the dead of night. My work hours eventually went back to normal however I had fallen hard for headphones and was now in search of that perfect sound signature to compare to my WF-34 Icons.
Over the past two years I have gone through the gauntlet of headphone research; Buying, trying, selling, returning, auditioning, inconveniencing, and frustration are but a few words to describe my journey. I had been eying the M4U 1 since I first read about them back in 2013, however I had neither found a retailer with a pair on demo, nor did I actually find one that had them in stock. As a hi-fi guy, Paul Barton is my loudspeaker idol. I have been an admirer of not only his work but PSB Speakers for years, and the technology behind Room Feel looked incredibly promising. It certainly did not help my envy that popular review sites such as Innerfidelity and TheWireCutter raved about both the NAD Visio HP50 and the PSB M4U 1/2. In the end I settled for a few pairs of popular hi-end headphones. The deciding factor was not so much based off from one definitive reason, rather overall sound quality vs the low price I was able purchase them for. By a stroke of luck or impeccable timing, in late November of 2014 a popular nation wide electronics chain put the M4U 1 on sale for 50% off, and by chance my local retailer, one the first day of the sale, had one left. In fact, it was the last one available chain wide in all of Western Canada. My ride on public transit seemed like an eternity but in the end I came, I saw, I conquered! Fantastic!
PSB ‘Music For You’ : M4U 1
Frequency Response (within +/- 1.5dB)
20 Hz - 20,000 Hz
Total Harmonic Distortion (1kHz/1mW)
Size (W x H x D)
Ear Cushion Outside / Inside (aprox.)
200 x 200 x 70 mm
68 x 98 x 17 mm / 45 x 64 x 15 mm (aprox.)
Designed and Engineered in Canada, Made in China
Packaging and Accessories
Protective Hard Travel Case
Airline Connection Adaptor
Upon pulling off the sleeve to the box, I really felt like PSB was providing me with a premium product. The box is made of 100% recycled materials and flips open like a book. Inside neatly sat the hard travel case which stored the headphones, with 3 bundled accessories bags located under the flap of the left tray. Included in first bag is a quality 3.5 mm to 6.3 mm gold plated adaptor, a universal airline adaptor which will greatly appeal to frequent flyers, a carabiner for easy attachment to bags or luggage, and a micro-fibre cleaning cloth. Unlike what most manufacturers provide, the cleaning cloth is actually of useful size and thickness; So often you get a small 45mm x 25mm piece of cheap polyester that is smaller than what PSB provides, folded up. The next bag included two headphone cables; One standard straight cable, the other with a one-button control-talk module that is guaranteed to work with at least iDevices and Blackberry phones. The last bag contained the extra set of leatherette ear-pads and replacement instructions. I can’t tell you how much this is appreciated as tracking down and ordering a replacement set of ear-pads can be a real hassle, not to mention unnecessary listening downtime. I also applaud PSB for including shaped inserts to prevent loss of form when stuffed in the case.
All of the accessories fit neatly into the high quality, light weight, hard travel case and are held firmly in place by the mesh. Having traveled with the case attached to my bag via the carabiner, I can assure you that everything was held secure in place. Although not pictured, it is both possible and safe to keep the headphone cable attached when the M4U 1 is folded in the case. Simply put, all aspects of packing and travel have been smartly addressed.
Build, Aesthetics, and Comfort
As expected of a company such as PSB, the M4U 1 are of high quality build and construction. Holding these in my hand, they do not feel cheap or flimsy, yet reasonably light. Multi layered thermoformed polycarbonate reinforced with ABS make up the bulk of materials used, ensuring both strength and light weight. Stainless steel extensions run down into the arms and are reinforced at the fold point with a metal plate, which is screwed on to the headband. The ear-cups are attached to the yoke via a brushed-stainless backplate which acts as an up/down pivot. In the centre of the backplate sits a chromed nickel PSB Speakers logo which also acts as the left/right swivel. Located on the bottom of each ear-cup is the 3.5 mm entry plug. The dual left or right entry plugs is a handy feature allowing you to not only daisy-chain another set of headphones, but alleviates the annoyance of either the phono jack or source equipment being on the opposite side of the cable. The stitched ear-pads as well as the head-pad are made of a very high quality leatherette. The material is very soft yet strong and if one did not know better, would swear it was real leather. The provided cables are decent enough. They are of good length, have no bad microphonics, and neither tangle nor have a bad tendency to keep their shape. Although I would have preferred that they would have made the cables a little thicker, it is not an issue as any 3.5 mm cable can be used.
|Buttery soft and breathable head-pad.||The high quality drivers are protected by a perforated hard outer shell.|
|Inside view of the arm at full extension.||Outside view of the arm at full extension.|
Available in Baltic Grey, Monza Red, and Black Diamond (pictured), the M4U 1 sports a modern design. Despite the Monza Red sharing a similar shade as a certain unmentioned ‘fashion’ headphone brand, the M4U 1’s profile is quite elegant and unique. The finish is made up of multiple layers of clear polycarbonate which helps achieve a deep, glossy appearance. Unfortunately the camera does no justice in portraying just how sexy the M4U 1’s finish is; They really need to be seen in person to fully appreciate their look. A narrow grey strip running along the middle of the body helps break up the solid gloss finish. The brushed steel back plate and chrome insert adds additional contrast and is a nice throwback to old hi-fi equipment design, adding that last bit of prestige to overall look. Essentially, the M4U 1 will have no problem fitting in when placed next to a modern HDTV or hi-fi stereo system.
Despite the high gloss, the M4U 1 is quite scratch and finger-oil resistant.
Ingenious 360 degree outer tilt / inner swivel design.
Check out that shiny, deep gloss coat!
The ear pads are very soft and comfortable.
Coupled with buttery soft memory foam ear-pads and the complete 360 degree axis of the ear-cups, obtaining a perfect fit should not be an issue. Having an average sized head and ears, the clamping force was sufficient to assure both a good seal and good grip, yet not overly tight with no unwanted and annoying pressure points; Once broken in, the ear-pads meld into the side of your head while still maintaining the proper buffer and cushion. Thanks to the wide arc of the headband the weight of the M4U1 is evenly distributed and never do I feel the full weight of 340 g bearing down on my neck. In terms of long listening sessions, I had no trouble wearing the M4U 1 for 4+ hours before I needed to take a quick break; Like with most closed headphones it was to alleviate and vent some of the heat build up, rather than discomfort due to fit. Overall the M4U 1 remained relatively cool and after a while start to become invisible on your head. Be warned though, people with larger heads and ears may have comfort issues in the beginning, but much like a pair of new shoes the M4U 1 will loosen up after some breaking in.
Despite being the passive variant of the highly acclaimed M4U 2 with ANC, the M4U 1 does an excellent job of blocking out unwanted background noise. Taking a walk down to the local convenient store, which is located along a busy street and multiple bus routes, it was impressed with how much noise the M4U 1 actually block; They are easily on par with custom fit ear-plugs. Although the included hard travel case and fold-up design means the M4U 1 is meant for portable use, in my opinion those features are meant literally for just that; Moving the unit from point A to point B with minimal hassle and packing as opposed to using them on-the-go in the urban environment. Nothing is going to stop you, besides the threat of looking like a Hipster, but due to their overall design they are mean for a more low-impact use. Fortunately PSB also makes the M4U 4 IEM which would be a better match for the urban warrior.
Pictured above are the three available colours, Paul Barton himself and a nice looking model from AudioImage sporting the M4U 1.
In terms of overall size, the M4U 1 are pretty average in comparison to other popular circumaural headphones.
Value vs Quality
PSB has been renowned and praised for their premium quality loudspeakers without the premium price, and the M4U 1 proudly carries that torch. If I were blind folded and had the M4U 1 placed upon my head with several tracks played, and then asked if the sound quality I just experienced warranted a $699 MRSP, I would have no reservations in saying yes. If instead I was asked if $499 was fair for the sound I just heard, I would agree that the M4U 1 are deserving of that price. At a MSRP of $299 PSB not only offers almost unreal quality and value for the price, but puts the M4U 1 in reach of the average consumer who want a premium sound, solid build, and plethora of useful accessories. By choosing to go with polycarbonate and ABS and outsourcing construction to China the savings were passed along to the consumer. Sure, PSB could have gone with more premium materials and had the units hand-assembled in Canada, but this would undoubtedly raise the total cost, potentially making the M4U 1 less attractive for those of us who may not be able to afford them otherwise. All of this is backed up by a 2 year manufacturer’s warranty.
The Sound - Basics
Click here for Head-fi’s interview with Paul Barton.
Room Feel Technology
What is Room Feel Technology? Ever heard DSP or software based headphone sound space enhancers such as Dolby Headphones, SRS, or Razor Surround? Room Feel Technology is nothing like them. Music is recorded, mixed, and mastered in a room with two forward firing monitors. The key word here is ‘room’. Essentially the music you and I enjoy is meant to sound it’s best coming out of two flanking loudspeakers, in a ‘room’. So what is so important about the ‘room’? When loudspeakers pump out sound, only a certain percentage of the sound that reaches your ears comes directly from the cones. The rest of the sound is being reflected off the walls, floor, and ceiling. Without getting too technical, the room actually gives the sound energy, and while that energy predominantly affects the lower frequencies, it actually gives body to the whole frequency response. Without this added energy the sound loses it’s potential resulting in a rendering that is not true to the recording. Up until now, not a single headphone manufacturer has taken the ‘room’ into account, despite having very similar frequency curves to the M4U 1. Thanks to Paul Barton’s genius, the M4U 1 sound not like conventional headphones, rather sound like a really good pair of loudspeakers properly positioned in a room with you the listener sitting in the sweet spot.
It is a lazy Sunday afternoon, nothing better to do you go down to your local hi-fi store with the intent of picking up some speaker wire and perhaps a CD or two. Being a slow day, the salesperson ushers you into a sound room and proceeds to give you the full demonstration of the store’s most expensive amplifier and loudspeakers. Having a decent hi-fi setup at home, you initially agree simply to indulge him only to emerge from the room having listened to quality of sound that you did not think was before possible. This scenario perfectly describes the M4U 1.
From the moment I placed the M4U 1 on my head and pushed play, I was absolutely blown away at how bloody good they sounded, from a loudspeaker perspective. Though not for one second did I ever doubt the claims of Paul Barton and the Room Feel Technology developed by NAD/PSB, truthfully I was not knowing what to expect; A small part of me kept saying ‘Buzzword’ and ‘Overhyped’ every time I read ‘Room Feel’. All reservations went out the windows once I heard how clean, resolving, and BIG the M4U 1’s sound was. Initially the M4U 1seemed like it had a slightly warm tilt, but after further listening I soon realized this was not warmth I was hearing, it was full body across the whole frequency spectrum; Nothing sounded weak, distorted, coloured, or out of place. After playing the Headphone Dating Game over the years, this truly was love at first sight…or hear.
On Christmas Eve I had decided to bring my iPod and the M4U 1 over to my parent’s. It had been a little over one month since the initial purchase and while I had been impressed with their overall performance, I saw this as an opportunity to get a pooled opinion from both music lovers and professionals. Having all festivities take place downstairs in the rumpus room, I strategically placed the iPod and headphones on the kitchen table that everyone would need to pass on their way to the only bathrooms on the main level; New technology in my family is as enticing as a flame is to a moth. It wasn’t long into the night’s festivities before I heard someone say “ By the way, who’s headphones are those upstairs? “ and the talk turned to the M4U 1. Although it could have been “ PSB makes headphones? ”, out of a group of around 25 family members the top remarks were how ‘clean’ and ’natural’ the sound was, followed by “ These are how much? “. Most agreed that the vocals were some of the most natural and forward sounding they had heard in a pair of headphones; All agreed that overall, the M4U 1 put their beloved (and more expensive) headphones to shame.
Normally I would blather off any and all information on the tech I am showing off before I hand it off. It was both refreshing and rewarding to get unprompted opinions from people who are well informed. I would like to conclude by saying that this time I had said absolutely nothing about the M4U 1 to my family either before or after their listen. Not Room Feel Technology, not their frequency response or impedance rating, not even my own personally feelings. Besides stating that the M4U 1 were made by PSB Speakers and that I had got them for a half-off, the only thing asked by me was in regards to their opinion on the overall fit and comfort level, which received no complaints. My sneakiness and curiosity not only validated my own thoughts on the M4U 1, but every other review giving them high praise; Impressive for a first go!
Frequency Responce Curve
First thing that I would like to disclose is that the above FR graph is a compilation, averaged from many sources found on the internet. I have no means of measuring headphone sound output, and did want to cut and paste an FR graph taken from another site. Instead I thought it would be better served if I compile and average the data pulled from both professionals and enthusiasts measurements. Although most of the FR curves for the midrange were consistent, there were two common variances I encountered in the bass and treble regions. The bass curve on some graphs displayed a steep shelf starting at 30Hz extending down to 20Hz, while other showed consistent curves yet the amplitude of the whole treble zone was about 5dB higher. Oddly enough, both variances were more common amongst enthusiast blogs rather than websites of a more professional nature (such as Innerfidelity). Regardless, I can assure you that the FR response graph is both honest and accurate. Not to mention looks nice and is easy to read.
The frequency response curve of the M4U 1 is actually common in premium top-tiered headphones from manufacturers such as Sennheiser, HiFiMAN, and Denon. Slightly enhanced bass, linear mids, and treble with a gentle roll-off is what many audiophiles consider to be the proper FR curve; It is not surprising that manufacturers would choose to tune their drivers this way. While I personally have not heard any top-tiered planar magnet headphones, I have heard some of the the best of the best when it comes to the dynamic transducer variety; The quality of the M4U 1’s driver holds their own against it’s more established competitors. However as good as numbers and charts are in determining a baseline reference, real world performance is where it counts. This holds especially true for the M4U 1 as the Room Feel Technology adds noticeable effect that helps distinguish itself from the competition.
Music is quantified by more than just the bass, midrange, and treble and therefore I am not going to spend too much time going over the tonal qualities in great detail. My reasoning behind this decision is that overall, the M4U 1 handles the whole frequency spectrum exceptionally well with no perceived negatives or shortcomings, and I would rather put forth the time and effort into covering the many other aspects of the sound.
Bass: The M4U 1 has some of the most accurate, detailed, and fast bass I have head in a dynamic transducer. There is absolutely zero sub-bass bloat nor bloom, and absolutely zero bleed into the lower midrange. When called upon the M4U 1 delivers mid-bass punch as well as sub-bass rumble that is accurate in quantity yet gives gives a good sense of power and energy without being over-bearing. Room Feel Technology not just works, it works very well; It is as if the bass is a separate entity that cleanly and seamlessly compliments the rest of the frequency spectrum. Whether it is the low registers of a double bass, or the fast electronic beats of todays modern music, the M4U 1 has no problems accurately handling the low frequencies in any genre.
Midrange: One word; Smooth! Despite being relatively linear, the midrange has an engaging sound. Instruments are rendered with great precision. A slight bump at the lower end adds body to male and female vocals, which are accurate with no hint of grain or veil. Dialogue is clean, clear, and precise. Considering the midrange makes up the bulk of the sound, the M4U 1 handles the diversity uncoloured and with ease.
Treble: Like a perfectly fermented champagne with just the right amount of sweetness, the M4U 1’s treble is crisp and clean with a touch of sparkle and shine. Fast and detailed with accurate decay, the treble is non-fatiguing. Sibilance sounds natural with no accentuation or harshness. There is no perception of artificially boosted or unnatural detail. With a gentle roll-off, he treble is what it is, sweet; Great extension, non-peaky, zero distortion.
Perhaps one of the more prominent aspects of the M4U 1 is it’s soundstage. Simply put it’s huge, and not just for a closed design either. The overall soundstage is not as airy as an open back design, none the less the M4U 1 either rivals or surpass headphones of that nature. A good analogy would be that the M4U 1 sounds like the music is being rendered in a large room, whereas a good open back headphone sound like the same large room but with the windows open. Another interesting quality of the sound stage is that despite having drivers that are aligned flush with the head, the overall directionality of the sound is more indicative of two angled loudspeakers rather that of a general left/right circular radius commonly found in a closed circumaural design. This provides exceptional forward depth that is both wide and tall. Overall the stereo transition is not only natural but seamless; The M4U 1 do not have a left/right/centre ‘3-blob’ soundstage, nor do they have an obvious centre break exposing the left/right divide. Instrument and vocal placement is precise, accurate, and natural.
Amping and Scaling
The M4U 1 are rated at a standard 32 Ohm with a sensitivity of 102 dB, meaning one should have no problem achieving good sound out of virtually any device that has a 3.5 mm phono jack. While the M4U 1 certainly could benefit from a more powerful amplifier, I was surprised how universally good they sounded coming out of devices such as an iPod, HDTV headphone jack, Micro Gameboy Advanced, or a PC’s onboard audio. Equally surprising was how easily the M4U 1 took to both EQ tweaking and bass-boosting circuitry, showing little distortion and scaling nicely to the adjustment. Overall, it was difficult for me to find a source where the M4U 1 sounded weak, underpowered, or unrevealing; A true testament to their engineering.
How many times have you read that ‘ X ‘ headphones are great with Rock and Country music but fall flat when it comes to Hip-hop or Dance. Or perhaps that ‘ X ‘ headphone sounds marvellous with uncompressed Classical or Jazz yet don’t do modern music justice? Sometimes ’ X ‘ headphones sound very musical but may not be ideal for a competitive gaming session. When it comes to overall versatility, the M4U 1 may as well be nicknamed “The Jack of all Trades” as it handles all forms of sound reproduction with absolute precision, speed, and clarity; There is not one single specific type or genre that these headphones cannot handle, period. This can be attributed to the actual science behind Room Feel Technology, and helps reinforce Paul Barton’s claim that headphone manufacturers need to realize it’s importance and incorporate the ‘room’ into their sonic design.
Whether it be a highly compressed lossy track or a lossless hi-res DTS soundtrack the M4U 1 simply refused to ultra-highlight any ugliness of the sound. Unlike other headphones where the more detailed and resolving they are the worse poorly mastered tracks sound, the M4U 1 holds it’s composure. Although I am not going to deny the fact that you will hear flaws and imperfections in certain recordings, I will say that the M4U 1 handles these issues with grace. Loud / low DR scale lossy tracks commonly found in virtually all modern music are very tolerable, while 24-bit / 96 KHz+ lossless tracks sound simply stunning. It is as if the M4U 1 shows compassion for the poorly mastered while allowing fine detail to shine with recordings of higher quality, all while being 100% passive. My hat goes off to the great engineers who helped design the M4U 1 as I can now revisit my music library and not worry about what is coming up next on the playlist.
The Sound - Review
Mac OS X 10.10.2
AIFF lossless source files
TosLink (optical)—> Teac UD-H01—> Ultralink 3.5mm interconnect—> M4U 1
Angel of Harlem - The Persuasions
Three For All - The Bucky Pizzarelli Trio
Bring it On Home - C.C. Colletti
Midrange purity is perhaps one of the most important qualities necessary for sound reproduction. The body of the sound (voices or instruments) comes solely from this frequency range. So often voices, despite sounding clean and accurate, sound detached from the ‘physical body’. While this can be contributed to the recording itself, the hardware plays an equal role in the presentation. ‘Angel of Harlem’ by the a cappella group The Persuasions is a good example of vocal midrange purity, and the M4U 1 beautifully creates an excellent awareness of body. Each voice of the five members had a good sense of chest, sounding like it was resonating from within the diaphragm rather than that of five floating heads. Detailed and full of life, from the deep baritone lows to the silky smooth highs, the tonal qualities of each members voice were as uniquely distinct as they were visceral. It truly sounded like there were five men singing in front of three microphones.
Instruments can too suffer from a lack of body, especially with today’s preference of over-processing and the quashing of the dynamic range in recordings. Thankfully ‘Three For All’ as performed by The Bucky Pizzarelli Trio does not suffer from the latter. This jazz trio, consisting of three guitars, is a good selection to best illustrate the sense of a physical body in an instrument’s sound. With unadulterated transparency, every pick, every strum resonated within the shell giving way to a full bodied experience of sound accuracy. It was as if each note was it’s own entity occupying it’s own space within the guitar, being both well defined and tactile in nature while maintaining cohesion to the sound. While this piece was purely instrumental, the performer’s energy was apparent through both their playing and their humming along to the rhythm.
Recorded at Chesky Labs with the latest in Binaural+ Technology, the Led Zeppelin cover ’Bring it On Home’ as performed by C.C. Colletti is a good test of midrange purity in a natural environment. I decided on this song because it was the sole track on the album that has a male voice accompanying Caroline’s, and because he is occupying the same space as his guitar the vocals can get garbled in to the strumming and sound grainy. Providing excellent body with perfectly rendered timbre, the M4U 1 handled this trouble with ease, cleanly separating the two sounds giving both the singer and instrument their own space while still maintaining their relative position to one another. Of course, the songs highlight is that of C.C.’s sweet Southern voice. Full of energy, her vocals sang out with complete transparency; The textured raspiness of her voice was smooth with not even a hint of grain, reaching the top octaves with perfect clarity. Every strum of the guitar yielded the individual reverberation of each string, while the harmonica belt out it’s notes with an echoing sense of soul. Modestly sitting off to the far right, a weighted feel of power emanated with every pluck of the upright bass, filling the studio with a deep lucid sound.
Bass Resonance- Best of Chesky Jazz and More Audiophile Tests, Vol. 2
Ain’t No Sunshine - Christy Baron
Up On You - Coming Soon
When pushed, a headphone’s driver can produce unwanted and nonmusical sounds. This what is commonly referred to as distortion and the sound produced can not only lose it’s overall detail and resolve, it can cause bloat and bleed into the the lower midrange. It is far too common for headphone manufacturers to artificially boost the lower frequencies to compensate for their tendency to distort. This may be appealing for both modern recorded music as well as the younger generation’s preference for BIG-BASS, it is hardly ideal for listeners who want quality over quantity. The M4U 1 not only have the speed, the power, and the accuracy, they have the energy with the ability to reach DEEP when called for; Response is solid down to 26Hz with a gentle roll off down past 20Hz.
The tracks I chose for this section are a good test of both natural as well as artificial (or synthesized) bass resonance. First, ‘Bass Resonance- Best of Chesky Jazz and More Audiophile Tests, Vol. 2’ features a solo stand-up bass approximately 3’ from the mic located in a large studio. Every note featured a sharp transient pluck followed by the deep resonance of the body. There was a human quality to every pluck with real sense of flesh pulling on the strings which twanged and reverberated along the frets. Never was the response boomy or bloated, just a pure, clean sound with power and energy felt with every note.
Moving along to ‘Ain’t No Sunshine’, again featuring a solo upright bass but this time accompanied by Christy Baron. This is a good test at showing the power and control of the bass when challenged with maintaining transparency to the midrange. Once again the M4U 1 masterfully handled the bass with precision and control with absolutely no bloat nor bleed. Every note resonated with each pluck showing both energy and grace. Christy’s sweetly seductive vocals were rendered with such subtlety and clarity, giving a good sense of breath yet the M4U 1 refused to lose control of the lower bass, never overpowering or shadowing her voice.
This section would not be complete without a true test of extreme bass. For this I chose the trance/electronica track ‘Up On You’ from the Audiophile compilation by Audiomatic. As one would expect from this genre, this track features impressive amounts of elevated mid-bass and sub-bass. The M4U 1 was able to deliver mid-bass punch with authority, yet still revealing the nuanced low frequency textures of the electronica sounds. Sub-bass possessed impressive amount of weight and energy and was rendered with such speed there was simply no time to bleed into the higher frequencies. Simply put, the M4U 1 is more than capable of supplying ample but appropriate bass when needed, but nothing more. Bass-heads will be more than satisfied with the output quantity while audiophiles will pleased with the quality; Both will impressed with the absolute control.
Spanish Harlem - Rebecca Pidgeon
Allan Taylor - Colour to the Moon
Hajji Baba - Monty Alexander
The audiophile classics I chose are a good test of the M4U 1’s ability to render fine detail and it’s overall resolve. Featured on several female vocal reference compilations, masterfully recorded in Binaural stereo, ‘Spanish Harlem’ by Rebecca Pidgeon contains high resolution detail that can be easily lost if the driver is unable to adequately perform; Not so here. Rebecca’s voice sounds very natural and just breathes with a good sense of space all around her. Every subtle in-between breath she takes can be easily discerned, and never did the sweetness of her vocals sound peaky nor possess any grain. The bass sounds full, robust, and detailed, never getting in the way or sounding overpowering. The strings are airy and sweet yet don’t sound detached from the rest of the band. The shakers are located in the back of the soundstage but don’t sound distant, with each shake being unique and distinct. Nothing sounded congested or out of place, all while maintaining excellent transparency.
‘Colour to the Moon’ by Allan Taylor is one of B&W Audiophile Recording’s favourite reference tracks, as is mine. Alan’s voice is beautifully rendered with detail and emotion; Trenched with warmth it’s deep sound saturates the sound-space. Filled with both joy and sorrow, the delicate picking of the acoustic guitars render great resolve; Every strum glistened with texture, almost visceral, with detail so precise that I could feel the edge catching the coil of the strings as the pick glided across the surface. Possessing an almost holographic quality, the bass cleanly resonated from the back with deep, enveloping, and powerful detail, yet never sounding overwhelming to the contingent of sounds. Distant but never shadowed, the seductive sound of the saxophone gently echoed it’s tune from a far.
Equally impressive is how the M4U 1 render the finer details in Monty Alexander’s ‘Hajji Baba’. The percussive strikes of Monty’s piano were as dynamic as they were subtle; Every note, every chord was distinct, full of energy while maintaining transparency and clarity. Besides Monty’s dynamic piano work, this track features percussion with a dazzling array of cymbals, and is why I chose this piece in particular. Each explosive strike of brass resonated with excellent attack and release resulting a a multi-layer of textured and shimmering sound with a touch of sparkle. Never did the cymbals sound thin, brittle, or weak yet possessed an almost ethereal delicacy. The beat of the drum, though not as forward as the rest of the kit, had both body and impact. The upright bass sat politely behind the rest of the music, each pluck robust, weighted, and detailed yet remained modest.
Transparency and Focus
SlÂttar pÂ tunga - Springar Etter Gudmund Eide - Berit Opheim Versto
Haydn: String Quartet in D major, Op. 76, No. 5 - Finale - Presto - EngegÂrdkvartetten
Wa Wa Wa - Candido Camero
Transparency can be defined as sound that is clear and uninhibited, while focus refers to the definition or ‘clarity of outline’ of that sound. Without these qualities, instruments and vocals can sound cluttered with the notes sounding fuzed together thus taking away the natural detail and convincing resolve. ‘SlÂttar pÂ tunga - Springar Etter Gudmund Eide’ is a trio of female yodellers and best illustrates the transparency and focus of the human voice. The rapidly fluctuations of the falsetto were rendered with absolute clarity, speed, and precision. The characteristics of each singer’s voice were trenchant in their execution; Vocals were full bodied and had a feel of naturalness, each breath having a sweet innocence. Well defined and coherent, there was no muddled notes, no grain, no harshness, just an open window to the sound.
‘Haydn: String Quartet in D major, Op. 76, No. 5 - Finale - Presto’ as performed by popular string quartet EngegÂrdkvartetten. While four stringed instruments may sound simplistic by definition, the complexity of their sound is not; This piece boasts very fast and dynamic bow and finger work by the performers. Each performer’s instrument exists in their own transparent space with their relative positions apparent to the listener. The sharp transients are perfectly complimented with the airy, dry yet sweet sound of the reasoned bow; Fast and detailed, well textured and defined, every note exhibited both energy and life. Both transparent and focused, the characteristics of each instrument was easily discernible, highlighting the M4U 1’s overall precision and resolve.
Finishing off this section, Candido Camero’s ‘Wa Wa Wa’ is a fun Binaural recording. Set in a large soundstage, mixed with dynamic sound of brass horns, this track features a plethora of funky percussion and voice work. With a good sense of impact, each strike of the hand against the skin resonated from within the drum’s chamber, sounding detailed and discrete with a focused outline of it’s shape; I got a good sense of not only the position of each drum within the sound-space, but the position of the performers hand or mallet upon the instrument. Cymbals explode with a textured shimmering sparkle. Distant yet easily discernible and well rendered, the vocals relayed the performer’s vigour giving way to a sense of natural energy. The crisp, bright sound of the brass are focused, possessing good bite that excites the senses while maintaining excellent transparency. Though subtle, the guitar sits gently behind the percussion but is not overshadowed with each pic presented with great detail and resolve. Nothing sounded cultured, just pure musical glue.
Dr. Chesky's Sensational, Fantastic, and Simply Amazing Binaural Sound Show
Dr. Chesky’s The Ultimate Headphone Demonstration Disc
There is no better studio that better understands natural depth than Chesky Labs, and I can think of no better compilation of test tracks that would be more fitting. In all honesty, I did have my reservations at first by choosing to go with Binaural recordings. As good as they are at creating a more realistic sense of space and natural depth, more times than not I found Binaural recordings to be lacking in absolute precision. This is not the fault of Binaural technology, rather the inability of the headphones. Manufacturers unfortunately try every trick in the book to artificially create depth with the end result being a more expansive soundstage but one that sounds distorted or unnatural. For example the Height Centre Bell : Test track would indeed give an excellent sense of a rising sound, however that same height test on either the left or right channel were not straight; The sound would be skewed and follow the shape of the headphones cup as opposed to a straight rise. With open backed headphones, left/right height can be presented with more of a recessive step-out (or what I like to call sound floating away) rather than a convex curve.
The M4U 1 are a good example of Binaural technology sounding right. Whether it be the height tests, the walk-arounds, or the surround voices, each position of the sound was not only precise but natural. There were no skewed lines, each voice seemed to emanate from where they were announced, and never did elliptical walk-arounds sound flat instead perfectly followed the instrument’s path. There was an realistic sense of natural depth with each announcement of distance from the microphone. Whether it was 3’ or 30’, I believed the instrument or voice I heard were in fact recorded at that distance. It was surreal, almost haunting when Dr. Chesky announced he was about 30’ from the mic on the right side and started walking closer and closer, announcing his movements until he stops right before my and whispers into my ear “ Only Binaural technology can do this… “ ; Not only was it convincing that he was walking towards me in a large cathedral, I could literally feel his breath upon my ear. Perhaps one of the most impressive examples of natural depth was when Dr. Chesky gave me a virtual shave. The movements and precision of the sound were so believable it made my ears twitch in reflex thinking a razor was about to clip them.
Rhythm and Pace (PRaT)
This Song is For You - Johnny Frigo
Sweet Georgia Brown - Montey Alexandar
Para Los Rumberos - Santana
Rhythm and pace, otherwise know as PRaT, by definition is quite ambiguous and is often overlooked. This term gets thrown around a lot, and often incorrectly used. Essentially, rhythm and pace relates to the overall energy of the track. It demands a physical response to the music and should make the listener want to bob their head, tap along with their foot, or get up and dance. Since PRaT can only be quantified as a whole, I won’t be breaking down each song individually as they are only listed for reference; The tracks I chose offer up the potential to make the listener get up and move. Thanks to Room Feel Technology the M4U 1 dominates in it’s ability to relay the energy of the music. Whether it’s the fast latin rock of Santana’s ‘Para Los Rumberos’, Johnny Frigo’s dynamic jazz trio playing ‘This Song is For You’, or the visceral sound of two bands facing off in Montey Alexander’s ‘Sweet Georgia Brown’, the M4U 1 makes short work of all of these tracks. Lively and natural, tactile and detailed, resolved with speed and accuracy, I got an excellent feel of the performers energy being relayed through the transducers that was as palpable as it was visceral. Before long I found myself tapping along to the rhythm with my fingers upon the keyboard. Of course there is a common tendency of the listener to turn the volume dial to 11 when rocking out to rhythm and pace, and the M4U 1 says to this an enthusiastic ‘Yes please!’. At higher volume the sound remained undistorted, allowing me to feel the full impact of the energy while the frequency response remained true to it’s form.
In all honesty, I could have transplanted any song from one category to another. The M4U 1 made short work of any track I chose. Detailed, textured, clean, transparent, natural and pure, it is difficult for me to find anything negative to say about their overall sound. Do the M4U 1 sound perfect? To my ears they do. Is there any aspects of the sound that could use refinement? Absolutely. Not because I feel there is anything lacking, rather I believe that nothing is ever technically perfect, especially technology; There is always room for improvement to be had with anything and everything. In fact a little birdie told me that PSB is working on a new flagship headphone. Ok, it was Paul Barton himself hinting at Head-fi’s Jude when asked what he is working on next. Needless to say I look forward to seeing what PSB does next.
“ Hey Paul, if you are reading this I just want you to know that it would be awesome if I can get a sample pair for review purposes when that day arrives eh! “ :)
First and foremost I would like to thank you good folk for taking the time to read my review of the PSB M4U 1. If you didn’t think it was a good read, I hope at the very least you found it to be informative. In writing this review I gained a new found respect for people who have written many themselves; It was quite daunting trying to decide what to write, let alone the format. My initial intent was to write a quick praise for my new favourite headphone, but the more I wrote the more I felt the need to write more and before long I found myself angling lights and setting up my tripod. It is quite obvious that I love the PSB M4U 1, and I felt it was difficult for me to stay objective. In all honesty, all I wanted to type in giant bold text under each section was ‘ Wow these are good! ’ over and over again. Considering that I live in a Capitol city with one of the highest ratios of retail:population, it speaks volumes (pun intended) that it was difficult for me to find a store that had the M4U 1 in stock. In my opinion, the M4U 1 are a true sleeper hit.
I tried to think of a good closing cliché that would best describe the M4U 1, but in the end all I could think of is that PSB and Room Feel Technology really hit a home run first time up to bat. They hit the ball so far out of the park it crashed through Zeus’s patio window and disrupted the game of back yard croquette he was enjoying with Jesus. You don’t have to go looking too far to find the many accolades the M4U 1 has received since their release in 2013. From making the list in Head-fi’s Buyers Guide, to The Wire Cutter having the M4U 1 as their top pick for two consecutive years, PSB’s first foray into headphones has accomplished what it’s competition has yet to even attempt; A sonic signature that takes into consideration the listening environment in which the music was intended to be heard. The end result of this forward thinking is one of faithful and accurate sound reproduction that holds true to the original recording. While there may be headphones who’s sound may be more refined or resolving, it’s not by much and nowhere near the price point of the M4U 1. Room Feel Technology is very real and is as much of a game changer as Paul Barton’s 1974 loudspeaker research was 40 years ago. It is time for the old guard to wake up and embrace a new standard in headphones. Le Roi est mort, vive le Roi!