Harman Curve –
The Harman Curve is definitely somewhat of a buzz word these days; in a nutshell, it is a subjective definition of neutral and a progression of the diffuse-field curve who’s most iconic realisation was by the Etymotic’s ER4 earphones. It was pioneered by Dr. Sean Olive, acoustic research fellow at Harman international who introduced a scientific approach to audio. He blind tested a wide range of listeners who gave subjective impressions on various sound signatures. Dr. Olive used a single model of headphone to standardize seal and ergonomics while simulating other models through an eQ. The listeners were then able to tweak the sound via bass and treble dials to their liking. Dr. Olve collected the results and sorted them based on the experience of the listener, age, gender and cultural background. Accordingly, he was able to find the exact signature that most listeners would prefer based on form factor and age. This isn’t a perfectly linear sound, but surely represents a sound target and the style of sound that is commonly preferred by the majority of trained listeners. Read more here.
With that said, the M5 TWS does indeed present a well-balanced sound, however, to my ear it is distinctly on the brighter side. Tone aligns with their reference focus, being neutral, and immaculate throughout. Lows maintain convincing weight and dynamics with sub-bass emphasis while a more even metered mid and upper-bass contribute to the neutrality of the M5’s tone. The midrange is clear and revealing, rising to a prominent 3KHz hump that enhances vocal clarity and presence. Meanwhile, the treble is fairly accurate with a crisp detail presentation and just a slightly brighter background. My most preferred ear tips were the memory foam tips that provided a slightly warmer and smoother sound in addition to the best fit for my ears. I listened predominately from my Google Pixel 4 connected over apt-x.
Where I am usually not a fan of micro-drivers, ADV.’s implementation provides some of the best extension and depth I’ve heard from this driver type, missing just a little physicality at the very bottom. Nonetheless, alongside moderate emphasis, sub-bass has good weight, providing a firm slam and rumble while also serving to increase the fullness of bass notes in general. Meanwhile, mid-bass and upper-bass are neutral in quantity and nicely linear, contributing to a neutral tone and high separation that form the foundation for the M5’s super-clean low-end.
Driver control is also on the higher side with just a slight loss of razor-sharp definition within the sub-bass where a hint of muddiness creeps in. As the mid and upper-bass are neutral, there is good resolution through these ranges and no loss of definition. Decay is very swift for a dynamic earphone, which contributes to high detail retrieval and a pacey presentation that keeps up with complex compositions. As the ADV. M5 TWS focusses on bass weight over punch and warmth, its sound is also quite dynamic. Its cleanliness through the mid-bass combined with the agility of its transients contributes to standout detail retrieval. Though sub-bass heavy tracks can challenge this earphone, its balanced and technically proficient presentation is a breath of fresh air in the TWS space.
Clarity and openness are both defining traits of the M5’s presentation and this is likely the most revealing midrange I’ve heard from a TWS earphone yet. That said, I would not consider it perfectly neutral or natural. As both the lower-midrange and upper-bass occupy a neutral quantity, vocals are imbued with accurate body and are neutrally toned. However, as the centre midrange climbs progressively, approaching a prominent 3KHz hump, the presentation is skewed towards the brighter side with enhanced vocal forwardness. As such, this can be considered a vocal-forward earphone despite having some degree of sub-bass emphasis. Conversely, this does operate in accordance with the Harman Curve to compensate for the lack of pinna gain for the in-ear form factor.
To my ear, it is slightly overdone and timbre isn’t perfectly accurate as a result. Nonetheless, the net result is clear, delicate and intimate if somewhat intense vocals. The midrange is highly defined, layered and revealing though female vocals consistently hold precedence over male. As the earphones return to linearity around the 4KHz region and remain impressively neutral through the lower-treble, vocals are appropriately articulated and devoid of rasp, thinness or sibilance. They are presented with ample density and smoothness so as to mitigate the effects of their increased brightness and clarity. Altogether, the M5 TWS is relatively forward and very revealing, though it has been well-executed to avoid overly skewing timbre. This is obviously not an earphone for those preferring a warm and smooth sound, rather it is energetic and moderately forward.
Though the midrange is bright, the high-end is quite accurate and linear so as to promote a non-fatiguing sound. Lower-treble sits in line with the bass and sits just slightly behind the upper-midrange. Instrumentation is very crisp with thinner body but ample texture nonetheless. They can sound more aggressive as a result, though treble isn’t sharp or metallic either. Foreground detail retrieval is excellent with precise attack and slightly truncated decay that saps that last iota of texture from instruments like cymbals. Treble then extends linearly before gently rolling off through the middle-treble with just a hint of sparkle from the highest octaves.
As a result, the background is quite clean and doesn’t glare over the earphone’s foreground detail presentation. There is a moderately high perceived sense of distance and width but, as with most TWS earphones, background detail retrieval is just average and there is no upper-treble sparkle or micro-detail. Nonetheless, the M5 TWS has the highest resolution of any TWS earphone I’ve tested so far. They are resolving of small details by combination of a linear treble tuning and an agile driver. Extension performs with the best in the category delivering impressive headroom and detail retrieval. Of course, wired performance cannot be expected here, but the M5 TWS is impressively resolving for its class.
With such characteristics, it comes as no surprise that the M5 TWS crafts one of the widest presentations for a TWS earphone, extending beyond the head with the ability to project a good amount of depth too. Imaging is standout, vocals possess a stable centre image, layers aren’t especially well-defined, however, the M5 has very sharp directional cues and swift transients that provide a keen sense of direction. Their similarly excellent separation emphasizes this quality, with neutrally sized notes within a spacious stage permitting the listener to easily discern space between instruments and focus on small details. As the upper-midrange is quite forward, vocals can occasionally overshadow background details in the midrange.
Lypertek TEVI ($90): The TEVI is, to my ear, slightly more balanced than the M5 TWS but at the cost of technical ability and separation. Bass extends better on the M5 TWS, delivering more defined slam and rumble. Both are tuned similarly, the TEVI has a touch more sub-bass, the M5 TWS a touch more mid-bass. Both are also well-controlled and highly defined, the M5 TWS has the edge technically with quicker decay and greater detail retrieval. Both feature forward centre midranges, however, the TEVI has lower emphasis and isn’t as bright and forward as a result. As its upper-midrange is slightly attenuated, the TEVI is denser, smoother and more natural but also drier. Meanwhile, the M5 TWS is more vocal forward, revealing and delicate. Both are neutral in tone and exceptionally clean. The M5 has a more prominent lower-treble, making it a crisper and more detail forward, it is the more detailed earphone by a fair margin. The M5 is more linear through the top-end and has better extension with more headroom and air. In turn, the M5 also has a substantially wider soundstage alongside better separation and layering. Both image accurately, however, as the M5 has more space to play with, its presentation is more involving.
Samsung Galaxy Buds ($149): A $50 premium brings superior technical ability and build quality. Both are voiced similarly as both target the Harman curve. That said, the Galaxy buds traces this more accurately with a slightly warmer voicing whereas the M5 TWS is slightly brighter and crisper. The M5 TWS has better sub-bass extension with more slam though it has less bass overall with the Galaxy buds being fuller and warmer. The M5 TWS is noticeably tighter with quicker decay and a cleaner mid-bass, creating a more defined and detailed but also leaner presentation; where I find the Galaxy Buds a bit sloppy and ill-defined. The M5 TWS has a brighter and more upfront midrange where the Galaxy buds are more even between bass and midrange with more body. Both are actually very similarly tuned through the midrange, but as the M5 TWS has less bass, it sounds brighter. As the M5 has slightly bolstered lower-midrange body it doesn’t explicitly sound thin but is certainly thinner than the Galaxy Buds and with a more neutral tone as opposed to a light warmth. The high-end is where the M5 TWS differs most. It has a crisper and more aggressive lower-treble. In so doing, it sacrifices a touch of instrument body and smoothness. However, the M5 TWS is noticeably more detailed and extended with a lot more air and headroom. It has a substantially wider soundstage and better separation, imaging also seems sharper to me.
Sennheiser Momentum TWS ($250): The MTW is more V-shaped and a lot warmer. Bass extends similarly well on the Momentum, however, there is more emphasis throughout, especially with regards to mid-bass. It has fuller, thicker notes that command more weight and space but also less control so texture is a lot smoother, missing small details compared to the more balanced, defined and quicker decaying M5. Mids follow suite, they are more laid-back on the MTW, more full-bodied and also warmer. The M5 TWS is substantially brighter through the upper-midrange delivering a lot more clarity and transparency. Meanwhile, the MTW is more powerfully voiced and easier to listen to for long periods of time but is also vocally recessed. Both earphones have a crisp lower-treble, it sounds more forward on the MTW by contrast to its less present midrange. The MTW has more instrument body where the M5 TWS is crisper and more resolving. The M5 TWS extends further, the MTW has a black background where the M5 TWS is brighter with a lot more headroom. It has a wider soundstage and more separation than the MTW, both have defined layers, however.
Master & Dynamic MW07 Plus ($250): The MW07 Plus is more U-shaped but similarly is tuned for clarity. The MW07 Plus offers superior bass extension with more physical slam and rumble. It has more bass emphasis throughout and is slightly warmer with more mid-bass focus. It has great driver control but doesn’t match the quickly decaying and more neutral M5 TWS in terms of fine detail retrieval. The MW07 Plus actually has a similarly tuned midrange, building in emphasis through the centre midrange to 3KHz focus. However, as its bass is more present, it is a fuller and slightly warmer presentation. Furthermore, the MW07 Plus has a sharp dip at 4KHz which makes it a lot smoother and mitigates its forwardness. Meanwhile, the M5 TWS is more revealing, even clearer and also more resolving. The MW07 Plus has a warmer lower-treble that is similarly crisp but has a darker background and more instrument body. Meanwhile, the M5 TWS is thinner and more aggressive with more headroom and air. The M5 TWS has better extension yielding higher resolution and aiding sparkle and background detail retrieval. This grants it a wider soundstage than the MW07 Plus, however, its layers are not so defined.
What once was fairly sparse market has now become so diverse that it is hard for consumers to navigate, an issue only further exacerbated by its youth. And yet, though only on their second generation of TWS earphones, ADV. Sound are already aiming their sites at the heavy-hitters, going toe to toe with premium offerings from companies with substantially higher marketing budgets. This isn’t fully represented by my comparisons, they are my honest words, yet they do not paint an accurate picture. This is because, my comments about the M5 TWS are in reference to earphones that aren’t especially balanced, making the M5 TWS an outlier. For this is a true audiophile wireless earphone and ADV. even traces the Harman curve to ossify their intentions. Furthermore, the M5 TWS offers all of the main conveniences of a top-tier TWS earphone; excellent battery life, stable connectivity and water resistance. It isn’t perfect, the midrange is a bit intense (but you can equally blame Harman for this) and the fit isn’t quite as locked-in as competitors with stabiliser fins. Should the user not like their sound out of the box, they’ll be confined to the eQ built into their music app of choice. Regardless, if you’re jaded by the V-shaped, sculpted wireless earphones out there, the M5 TWS joins the select elite of TWS earphones, offering class-leading resolution, a proper soundstage and very strong if not quite perfect balance.
The M5 TWS can be purchased from ADV. for $199 USD. I am not affiliated with ADV. and receive no earnings from purchases through this link.
Track List –
Anomalie – Metropole Part II
Arcade Fire – The Suburbs
Blazo – Colour of Jazz
Courtney Barnett – Tell Me How You Really Feel
Daniel Caesar – Freudian
Daryl Braithwaite – Rise
Dirty Loops – Next To You
Frank Ocean – Blonde
Fleetwood Mac – Rumours
Jimi Hendrix – Axis: Bold As Love
Kanye West – Late Registration
Mac DeMarco – This Old Dog
Missy Higgins – The Sound of White
Radiohead – Kid A
SOLE – Slow
SiK-K – iffy
ZICO – THINKING Part.2