7HZ AURORA: The Technical Adept Shimmering One

7Hertz or 7Hz is one of the audio companies that has its paradigm shift moments in the audio landscape in 2021. If you are a long timer in the audio enthusiast scene, who will ever forget their first product, the 7Hz Timeless which was considered as the gamechanger of the planar IEM market and a dual dynamic driver basshead-favoured set, the LEGATO.

To be honest, I only have a few product reviews on 7Hz items that I've published so far and this content will be a third one. This product that will be featured here is their latest midrange product and compared to other 7Hz products that I've reviewed in the past, this one is quite different.

This is 7Hz AURORA, their latest product that will cater the midrange segment and it is a hybrid driver set-up IEM earphone. This set has three types of drivers that were implemented inside and these are dynamic driver, new generation micro planar driver and balanced armature driver. Each type of driver was assigned to a specific part of audio frequency as it has its own distinctive electro-mechanical performance. The 12mm dynamic driver has a composite material on its diaphragm as its delivers a clear, deep and rich bass quality while the customised dual balanced armatures (probably a newer generation of Bellsings) is capable to deliver a crisp, clear and brimming sound on the midrange frequency and then the new generation micro-planar driver (I have some  intuition that this might a flat panel driver but need some more confirmation about this particular driver) will add more clarity, well-detailed on its resolution and copious amount of brilliance air. It seems that all these drivers were connected into three-way crossover circuitry for smoother, coherent, seamlessly flat and less distortion on its frequency response curve.

In regards to comfortability, despite its large frame for an IEM, the AURORA can give a very comfortable wear and comfort to my lugholes that I was able to wear it on long listening sessions. Passive noise isolation is quite excellent on this one as it really seals off some external noises from the outside.

The drivers and other components were encapsulated in a composite shell chassis in which the cavity base is made of an opaque 3D-moulded imported resin while its faceplate is a metal alloy with some titanium filament to give distinctive pattern-like banding on some steel forging process. The general dimension of the shells are on the large size just like most multi-driver hybrid sets and it has three ventholes on the top part for escaping some excess air pressure generated from its high performance dynamic driver. Regarding its interlocking mechanism for cable connection, it uses the standard 0.78mm bi-pin connector as it is the most stable and easier to detach.

As for its stock cable, it is truly a premium grade cable which is quite thick, durable and supple that it offers a less susceptible on entanglement. This one has 4-core gold-plated monocrystalline copper wires that were shielded with PVC insulators that are twisted and braided, and it has a modularity feature where we can change its termination plugs for output versatility that most modern audio devices have. The available modular termination plugs are 3.5mm single ended and 4.4mm balanced that were angled into a L-shaped form.

As for product packaging, the AURORA has a medium-sized rectangular box with some illustrations and information prints like basic specification and company addresses. The contents inside were well-arranged and organised as it gives a pleasant overall presentation.

These are the following contents inside of 7Hz AURORA's packaging box:

• Pair of 7Hz AURORA IEM transducers
• Stock cable
• A white-coloured pill-shaped carrying case
• Ear tips casing
• A pair of medium-sized balanced bore ear tips.
• 3 pairs of narrow bore ear tips in different standard sizes.
• 3 pairs of new generation of 7Hz high quality flexible silicone ear tips in different standard sizes.
• User's manual

In addition, I would like to introduce the latest 7Hz ear tips and they are made of pliable high quality silicone ear tips which gives an improvement of its brilliance extension, dynamic range and an increase of soundstage perception. It really offers me a very comfy feeling while having an excellent grip into my ears due to its tacky surface.

The 7HZ AURORA is actually easy to drive as it will amplify a good amount of audible volume level even from a device with decently normal gain output. But powering up on this set on the sources with a better amplitude level will sound even more fuller and vivid. I would like to share about this IEM on pairing and synergy on some sources, if I paired it to a more warmish-neutral or balance-neutral sources with some specified audio ICs like AKMs and Cirrus Logics, there are some noticeable smoothness and subduing those “digital glares”.

As for its tonality, The AURORA has a mild U to U-shaped (depends on the ear tips) sound profile with somewhat balanced presentation in all parts of the frequency range.

(Graph measurement was provided by [USER=516219]@baskingshark[/USER] , credits to his effort)

LOWS/BASS:

The bass response of this set is reverberating, precise, tactual and clean. It shows the quality of its bass region that makes this set's defining tuning. While it appears that it focuses more on subbass presence, it still balanced out with the ample texture on its mid-bass to give some semblance of authority and slam.

The deep, vibrant subbass presence can be perceived clearly on how it responds from subbass-focused instruments like low tone bass guitars, synthesisers, octobasses and drum machines. An adequate mid-bass texture somehow gives a sufficient note weight on instruments like bass kick drums, bass guitars, double basses, bass trumpets and male vocals like bass and bass-baritones. Bass kick drums have resonant, rumbly and sustaining sound on every stroke that even it can cope up with the fast double bass kicks on extreme metal tracks, bass guitars and double bass have rasping, sombre and resonant as both sets can be an accompaniment with music ensembles, the former instrument is for modern genres like rock, jazz and pop while the latter is for classical, operas and orchestras. Bass trumpets have metallic and a less fuller sound as it should have on its usual register, and as on male vocals, while it doesn’t have that depth and dark tone to give that guttural and booming voice but at least it has an ample weight with little vibrato to give  some dense and wool-like sound on bass and bass-baritone vocals.

MIDRANGE:

As on how it renders its midrange presentation, it is quite discernible on how it is slightly a bit notch on the overall frequency range of this set but it has a well-balanced texture on its note weight to give some heft and density on instruments and vocals with an energetic and shimmery sound on it to add more clarity and openness on high-pitched female vocals, strings and some woodwinds.

On male vocals, baritones have a smooth, velvety and lushness on their vocals which are excellent on both light and lyric types of baritone voice although while other types of baritones like Kavalier baritone, Verdi baritone, dramatic and noble baritones sounds somehow natural but they are a bit too mellow, milder and less powerful as these voices needs more warm and note density. Tenors vocals are excellent on this one as all tenor voice types either it is leggero, lyric, spinto, dramatic and heldentenor have a spiciness, brassy, dazzling and tinny sound on them while countertenors have a graceful, tender and softness on their vocals albeit a tad brighter to this set's energetic tuning nature.

As on female vocals, while contraltos have this smoky and full voice on this set, I wish that they have more weight and depth on them as it is a typical timbre characteristic on this particular vocal type. Mezzo-sopranos have those intense and bold sounds while maintaining a velvety and tender vocals as they convey a melodic and soothing quality. Soprano vocals are probably the AURORA's most strongest forte on how it depicts the quality of this particular vocal type whether it is coloratura, lyric, soubrette or dramatic ones as they sound crystalline, silvery and shimmering.

On how the instrument sounds on this set, it appears that they all sound organic and detailed as it is able to capture some of its tonal colouration but some added brightness. Strings instruments like guitars, violins and cellos, there's a crisp, presence and bright sound on every plucking on the notation strings of guitars, while the violins have a sparkling and vibrant sound on every motion on its bowstring and a clear, lively and incisive sound on cellos. When it comes to woodwinds, flutes have bright, rich and silvery sound,  have intense and brilliant sound, clarinets have bright and expressive sounds that evokes some pastoral theme on some orchestral tracks and saxophones have lively and reedy sound on them. As for brass instruments, trumpets have brilliant and vivid sound while trombones have penetrating and metallic sound, horns have a resounding, brilliant and metallic sound, and tubas have resonant and rumbling sound on them. Then on percussives, snare drums have clear, precise and sharp sound on every stroke, tom-toms have resonant and reverberating sound albeit it somehow lack of warmth, field or tenor drums have majestic, sonorous and reverberating sound on them, plate bells have some metallic and rich of overtones on them and kettledrums have dry, rumbling and substantial sound. Pianos have a well-balanced sound as it has a bright and even tone on its characteristic.

HIGHS/TREBLE:

Probably, one of the highlights of the AURORA's tuning to showcase its treble response. It is definitely on a brighter side of tuning but not that too intense or glaring that might ruin the overall balanced sound of this set. It has some emphasis on the upper-mids up to the presence part of the treble region to give a definition, detail and clarity on vocals and instrumental attacks. Despite the mild boost on those particular regions, I don't hear any stridency and the sibilance is kept under control although in some sibilant-laden tracks, I've encountered some occasional hissing sound. This type of tuning should take caution by some treble-sensitive folks out there due to its energetic and intense tuning of this set.

On the brilliance part of the treble, there's a copious amount of harmonics and well-defined sparkle and excellent treble air extension. On how it affects the tonal colour on each corresponding musical instrument, cymbals have bright, metallic and brilliant sound while hi-hats have a shortened buzz and sizzling sound. Glockenspiels on either mallet-types or keyboard variant, have this shimmering and brilliant sound on them and celestas have bright and lustrous sound that gives those “heavenly” and royal ball-like atmospheres.

SOUNDSTAGE, IMAGING AND OTHER TECHNICALITIES:

As I ascertain regarding this set in terms of technical facets, this is truly its strongest asset on why this set is such a remarkable performer in these aspects. We could clearly perceive its vast, spacious sound field with wide lateral span, excellent height reach and good depth distance from front to rear.

It does project an atmospheric and  three dimensional stereo presentation where I can accurately locate the placement of instruments and singer(s) in a well-layered soundscape with excellent separation on each element.

The cohesiveness of its tri-brid drivers works pretty well on how these drivers work in unison with a homogeneity performance. Dynamic driver has fast transient to deliver a pristine bass response while the balanced armatures gives a smooth yet detailed output that works in support with added airy ambience from the micro planar.

Resolution capability wise, both macro-dynamics and micro-dynamics are commendable on this set as it shows a solid note texture while having a sharp definition of micro-detail retrieval on how it extracts the nuances of notation attacks, vocals ends and room effects like reverberations.

PEER COMPARISONS:

AFUL PERFORMER 8

• AFUL PERFORMER 8 has a hybrid driver set-up consisting of a single dynamic driver and seven (7) balanced armature drivers. Unlike the Aurora, it doesn't have micro planar driver and its shell chassis is entirely made of medical-grade resin shell with a sandstone-like colour theme and also.it has a smaller size compared to the AURORA which makes it more suitable to all ear type sizes. While it also has quite well-accessories like the AURORA and also has a premium quality cable but it doesn't have a modular termination plug feature.
• As for tonality, it has a mild U-shaped sound profile but in some way it has an almost balanced-neutral type of sound that I'm quite adhered to. Compared to the AURORA, it has a bit tighter bass response, a less colouration on timbre and more natural sounding vocals and instruments on its midrange presentation and smoother and even treble response albeit it has less airy extension.
• On technicalities, the PERFORMER 8 has a bit narrower and less spacious sound/speaker stage if it is compared to the AURORA. But the rest of most technical performance, it has a similar capabilities collated with the compared set.

KIWI EARS QUINTET

• This is probably the closest one that I currently have in my collection of multi-hybrid driver set-up and I can definitely compare it with the AURORA. QUINTET also has a micro planar driver aside from dynamic drivers, piezo-electric bone conduction driver and balanced armature drivers that were arrayed inside. It also has a composite shell chassis like the AURORA although it is more compact and its faceplate is quite more minimalist. Knowing KIWIEARS, they are a bit meagre in terms of accessories and its stock cable seems decent but doesn't have a modular feature.
• This set has a mild U-shaped sound signature and it seems it has less coloured sounding compared to the AURORA. It has more subbass-focus bass response as it has more rumble with a decently textured midbass just to give enough slam, a linear and more neutral midrange presentation with a hint of transparency and a bright treble with good sparkle and air on it.
• On the facets of its technical capabilities, while it has a pretty wide sound/speaker stage size, my main concern was its depth as it is quite lacking in my opinion. But at least it has a remarkable stereo imaging presentation, layering, separation and coherency. It seems that it has a sharp micro-detail definition but its macro-dynamics is less solid.

To sum up my assessment about this product, for the past few days, I'm quite impressed with the overall performance of the 7Hz AURORA as it gives me that engaging factor to enjoy its coloured tuning. The most thing that I truly amazes me was it's overall technical performance as if it reaches some of the best midrangers and probably even some TOTLs that I've tested so far, spacious sound/speaker stage, atmospheric stereo presentation, layering or whatever technicalities we know to determine its performance of playback.

While there are some improvements in terms of tonality and its timbre as there are some noticeable colourations like a bit too energetic that causes some tinny and brazen sound characteristics to some vocals and instruments as it might be an issue to some treble-sensitive folk. But with its balanced tuning with good bass quality, transparent, vivid and spacious vocal presentation on the midrange and a detailed, sparkly airy treble response, these particular tonal aspects are enough to outweigh those concern unless if you want a neutral head, treble-sensitive or wants a more colouration on its particular sound profile.

7Hz AURORA is now available at LINSOUL, if you are interested in this product, there's a provided unaffiliated link below.

★★7HZ AURORA - LINSOUL★★

For more 7Hz product review, check out the following items that were outlined with links.

■ 7HZ LEGATO

■ 7HZ ZERO II

SPECIFICATION:

MODEL: 7HZ AURORA

IMPEDANCE: 30Ω

SENSITIVITY: 105dB

FREQUENCY RESPONSE: 5Hz – 40KHz

CABLE LENGTH: 1.2m

PIN TYPE: 2-PIN TYPE CONNECTOR

PLUG TYPE: MODULAR 4.4mm, 3.5mm

DRIVER UNIT(S):  (1) DYNAMIC DRIVER + (2) BALANCED ARMATURE + (1) MICRO PLANAR.

PROS:

● Durable composite shell structure.

● Regardless of its size, it fits well to my medium size ears due its smooth contours thus it provides better passive noise isolation.

● That metal pattern banding look on its faceplate looks pretty gorgeous.

● Tri-brid driver set-up has excellent cohesive performance.

● Like all midranger sets, This set has a lot of accessories.

● Premium-quality stock cable with modularity feature.

● Its new stock ear tips have the potential to be one of the best in the market.

● A well-balanced mild U to U-shaped tuning

● Reverberating and vivacious bass response.

● Fairly textured, dense and energetic midrange presentation.

● Perhaps it has some vocal versatility on it, excellent on tracking some tenors, countertenors, mezzo-sopranos and sopranos.

● Good for instruments with some metallic timbre like brasses and some woodwinds.

● Bright, airy and sparkling treble response.

● One of the most resolving sets that I've heard in the midrange segment.

● Outstanding overall technical capabilities, from sound/speaker stage up to the layering and separation.

CONS:

● Definitely not a neutral sounding one due to its coloured tuning.

● Instances of slight sibilance especially on sibilant-laden tracks.

● While it is not to be considered as strident, the energetic and tinny sound might be bothersome to some treble sensitive folk.

TRACKS TESTED: ( * = 16-bit FLAC, ** = 24-bit FLAC, *'* = MQA, '*' = DSD, *'= .WAV)

Alison Krauss -When You Say Nothing At All *

Jade Wiedlin - Blue Kiss**

Led Zeppelin - When The Levee Breaks **

Mountain - Mississippi Queen *

Queen - Killer Queen **

Guns N' Roses - Patience *'*

Eric Clapton - Tears in Heaven '*'

Sergio Mendes- Never Gonna Let You Go '*'

Pearl Jam - Daughter **

Roselia - Hidamari Rhodonite *

Assassin - Fight (To Stop The Tyranny)*

Celtic Frost- Visual Aggression *

New Order - Blue Monday *

The Corrs- What Can I do (unplugged version) *

Jimi Hendrix Experience - Voodoo Child *

The Madness- Buggy Trousers *

Metallica - Motorbreath **

Mariah Carey- Always Be My Baby *

Destiny's Child - Say My Name *

Malice Mizer- Au Revoir *

Mozart - Lacrimosa *

New York Philharmonic Orchestra - Dvorak- Symphony 9 " From the New World." *

Eva Cassidy - Fields of Gold (Sting cover)*

Michael Jackson - Give In To Me *

Exciter - Violence and Force *

Diana Krall - Stop This World **

Debbie Gibson - Foolish Beat *'*

The Sisters of Mercy – Lucretia My Reflection**

Suzanne Vega – Luka **

Lauren Christy – Steep *

Ottoman Mehter - Hucum Marsi *

Diana Damrau - Mozart: Die Zauberflöte*

Type O Negative - Black No.1 *

Felix Ayo - Vivaldi: Presto **

Three Tenors - Nessum Dorma *

Mercyful Fate - Witches' Dance *

P.S.

I am not affiliated to 7Hz  nor receive monetary incentives and financial gains as they provide me a review unit for an exchange of factual and sincere feedback from yours truly.

Once again, I would like to send my gratitude to MS. KAREENA TANG of LINSOUL for providing this review unit. I truly appreciate her generosity and trust towards me and other reviewers.