Friday, October 4, 2013

RHA MA750 Part.1: Aesthetics



Introduction

MA750 is a flagship model from an UK-based headphone manufacturer, RHA, who  recently have started getting noticed within the headphile community.


RHA MA750 Part.2: General analysis

Continued from Part.1, Aesthetics



According to RHA's website, they intend to "deliver the most accurate, comfortable and unobtrusive listening experience possible" to the users. And their proprietary Aerophonic™ Design along with hand-crafted drivers indeed represent such commitment.

RHA's description on their Aerophonic Design
In short, Aerophonic™ Design utilizes end-correction effect of a reverse-horn, and effectively attenuates the high frequency range. Consequently, an accurate frequency response shaping is possible once the horn is combined with a proper design.

The official frequency response of MA750
And surprisingly, the manufacturer voluntarily disclose frequency response charts of their products, just like Audeze and Etymotic Research, all of whom known for great sound quality. As it usually means they are well-aware of what they are doing, RHA must be very confident of MA750's sound.


Sunday, September 29, 2013

Sony MDR-CD950


MDR-R10, also known as the king of headphones to SONY enthusiasts, debuts in 1988. And the economic downgraded version, MDR-CD3000, follows right after along with other introductory models. These are known as the first generation CD series.

Starting from CD1000, which has a pair of bio-cellulose drivers within, the introductory models of the first generation CD-series have very similar sound signature from one another. And CD950 is no exception. While its appearance is almost identical to CD1000(except with its ear cushion material), an amorphous diamond-absorpt diaphragm is implemented instead.


Saturday, September 28, 2013

Unique Melody 3DD Part.1: Aesthetics



Introduction

From the China-based custom IEM manufacturer, comes great innovation; a triple-dynamic driver design, which is the very first in the industry. 


Unique Melody 3DD Part.2: General analysis


Continued from Part.1, Aesthetics.


Some people will call it an innovation, while the others say it is a crazy idea. A ⌀13 mm driver for the woofer, a ⌀8 mm driver for the mid-range unit, and a ⌀6 mm driver for the tweeter coupled into one IEM? That is 3DD, designed by Unique Melody, a well-known custom IEM manufacturer from the mainland China.

Oh, but they do not simply end there.. On the back of the woofer, there is an adjustable bass tuner made of a magnet, so that the damper, which is also magnetic, can stick on the woofer conveniently. As a result, the level of bass can be precisely tweakable, and the magnetic flux density of the woofer's magnet is effectively increased(thus its electroacoustic efficiency if the resulting B is any significant at all).


JAYS t-JAYS Three

Disclaimer: This product has been generously provided by Inks!

Driven with a pair of ⌀10 mm titanium-coated moving-coil drivers, t-JAYS is made for accurate sound reproduction and maximum comfort, according to the Swedish manufacturer.


And on top of that, in collaboration with Dirac, the company well-known for their custom sound optimization, JAYS come up with Curves specifically designed for t-JAYS models. While Dirac's DSP technology works most of the time, it may not do the job as well for some applications.


Friday, August 30, 2013

Astrotec AX60: A K3003 Clone from China?

Disclaimer: This IEM, which is not released in the US yet, is owned by a mutual friend of mine. Measurement has been carried out approximately 3 mm away from the reference plane with a pair of reference filter attached.

AX60 is Astrotec's new flagship hybrid IEM, featuring a dual balanced-armature transducer as a tweeter, and a dynamic transducer as a woofer. Currently, there are many hybrid IEMs, such as Audiofly AF78, Atomic Floyd SuperDarts, T-PEOS H series and Ultrasone IQ, in the market; The competition is indeed stiff. What is so special about this particular product then?



According to the manufacturer's calibration data, AX60 is precisely tuned to match the sound signature of AKG K3003, of which I consider as one of the best IEMs ever made. (but not my favorite)

The secret of K3003's articulate tonality lies in varying the size of front cavity and utilizing a tailor-fitted acoustic damping scheme. And of course, the technique is patent-protected not only in the US, but also even in the mainland China. If Astrotec have successfully reverse-engineered the sound quality of K3003 without infringing the patent, AX60 will certainly become one of the top contenders.


Monday, August 26, 2013

Phiaton PS210

Disclaimer: This IEM is owned by a friend of mine.


Phiaton is a high-end brand of South Korean company, Cresyn, which was formerly known as Leemax. As they have been manufacturing OEM products for Panasonic, Audio Technica, and many other well-known companies for a very long time, they must be well-aware of what they're doing.

...Or are they?

HiFiMAN HE-500

Disclaimer: Finally I am completely done with Rick's headphones- Now I need to work on his IEMs. In less than few weeks, the current batch will be finished! :)



As previously verified with Audeze LCD-2 Rev.2 and Fostex T50RP, planar technology finds its versatility in a dipole driving mechanism. Due to less physical constraint given on the moving-mass, a planar headphone generally has low acoustic output impedance, low distortion, and wide frequency bandwidth.

Since HiFiMAN products usually exhibit an acceptable level of electroacoustic peformance, such as that of the classic RE-series IEMs, expectation is higher than ever.

Saturday, August 24, 2013

HiFiMAN RE-262: A glory from the past

Disclaimer: This is owned by a mutual friend of mine. Measurement was carried out at 3 mm away from the reference plane using a pair of stock single flange sleeves.

Along with its low-impedance sibling, RE-272, HiFiMAN RE-262 has been known for its superb sound quality. Now their successors, RE-400 & RE-600, have proven to be rather a disappointment, it is perhaps a good idea to look back and check what's changed from the past. Have the current RE-models really devolved?

Sennheiser PX100

Disclaimer: This is one of the loan units Rick has generously provided for me. I'll get to the IEMs once I am completely done with headphones first. Measurement was little tricky to carry out, as the stock earpads were continuously being disintegrated due to aging. I did my best not to worsen its current condition.

PX100 is Sennheiser's classic supra-aural headphone. Although the model itself has been revised as PX100-II, and is not manufactured anymore, it is still considered as one of the best sounding portable headphones ever produced.


Friday, August 23, 2013

STAX SR-003 MK1: Electrostatic in the Ear

Disclaimer: This loan has been provided by my friend, vAsurada. This particular pair is SR-003 mkI, not mkII. Measurement has been carried out at 6 mm away from the reference plane with its headband removed.


Released as a Pro-bias version of SR-001 mkII in 1997, STAX SR-003 features small form factor compared to other full-sized headphone from the manufacturer for portable usage, and a 1.5 μm diaphragm, which is the same thickness as the diaphragm of current Lambda models.

And the question is, can this IEM perform as good?


Wednesday, August 21, 2013

Sony MDR-EX210

Disclaimer: This is the biggest surprise from Inks' stimulus package!

松尾伴大-san, who is the developer of MDR-EX1000 and the 5th ear mold master of Sony, states EX-series is designed to be as acoustically transparent as possible, by utilizing the essence of Sony's moving-coil driver technology, so that musicians and Hi-Fidelity enthusiasts can enjoy the sound quality alike. And although MDR-EX210 is just one of those random introductory models of the series, I see a great potential in it.


Maxell HP-CN40

Disclaimer: This is a part of the loaner provided by Inks, a good friend o' mine.

Not only Maxell is not a well-known IEM manufacturer, actually, I have never even heard of this Japanese company until very recently. 


Regardless, one of the main features of HP-CN40 is its oval-shaped nozzle. The manufacturer claim that the shape of the nozzle ensures a tight fit within the ear canal. Due to its unpredictable nature in acoustic design, changing the shape of the bore has never been realized by any IEM manufacturers as far as I know. 

Sony MDR-ZX700

Disclaimer: I am not even half way done with Rick's loan.. IOW, I've got a long way ahead! :)

Although ZX700 is a part of Sony's new generation of Studio Monitor headphones, according to 角田直隆-san, who is the mastermind behind the development of E888, D777, Q010, and 1R, the headphone is tweaked to suit the taste of ordinary listeners, rather than of studio engineers. 角田-san clearly distinguishes the difference between his Studio Monitor headphones and Sony's classic monitors:

from http://www.sony.jp/headphone/special/park/products_ms/tech1.html
"MDR-Z1000 is meant to be used outside of a recording booth, while MDR-CD900ST is specifically made for musicians residing inside of the booth. ... The sound, of which a musician hears on stage, is basically a cacophony of noise from various sources. Yet, by clearly distinguishing his performance from that of others, a harmony is created. ... On the other hand, a mastering engineer listens to the entire session, and accurately checks the tonal balance of the result."
And unlike its sibling, Z1000, which is equipped with a liquid crystal polymer diaphragm, ZX700's diaphragm material is made of a plain PET.

Sennheiser HD219

Disclaimer: This is another pair I borrowed from Rick.

Sennheiser HD219 is a low-cost, closed-air/closed-back supraaural headphone, which is designed for portable usage.


Apple ME186LL/A: A budget wonder [Revised]

[Updated on 08/21/13: Rick has provided a pair of MA850G/B for comparison. A brief comparison is presented here along with the result of his personal request.]

In September of 2012, along with the release of iPhone 5, Apple introduced their innovative earbud, Earpods. In addition, they revised their classic dual-balanced armature IEM, MA850G/B, to ME186LL/A. Other than the remote configuration, nothing is known about the detail of the revision.


First released in September 2008, Apple In-Ear Headphones was one of the earliest dual-balanced armature IEMs that were actually marketed for affordability, whereas its dual-driver competitors, such as Shure SE420&SCL4, Ultimate Ears Super.Fi 5 Pro, and Westone UM2 were considered high-end. Highly praised for its value by many Apple product users, nothing was really known about its electroacoustic property, other than the official frequency response graph shown above. Enigmatically, Apple not only set the y-scale unusually high, the x-scale was also unconventionally ranging from 1 Hz to 21,000 Hz, making visual assessment rather tricky.

Tuesday, August 20, 2013

Creative Aurvana Live!

Disclaimer: This headphone is one of whooping 18 loan pairs generously provided by Rick. I can't describe how grateful I am..

Along with Denon D1001, Creative Aurvana Live! is known as a clone of Foster's OEM model, 443741, which features a ∅40 mm bio-cellulose driver. Not only the specifications are identical, but also their exterior designs are very similar to one another. Of course, it doesn't necessarily mean 443741, D1001, and Live! should sound the same, but at least their electroacoustic potentiality should be on par.

Foster's patent documents indicate the mix ratio of bio-cellulose to carbon fiber is between 3:20 to 1:2, depending on how much of flexural rigidity is required in contrast to internal loss for a particular application, or vice versa. And in order to achieve ideal elasticity of the diaphragm for faithful bass reproduction, a separate edge, which is made of urethane elastomer, is utilized. Consequently, the driver is durable, water-resistant, and highly elastic with much lower 2nd/3rd harmonic distortion below 200 Hz compared to the electroacoustic characteristic of any of conventional PET drivers.


Saturday, August 17, 2013

Sony MDR-XB300



According to the designer of XB series, 松尾伴大-san, this first generation of XB-series (XB300 to XB1000) is specifically tuned for club-goers, who are frequently exposed to fast-paced bassy dance music. In order to accommodate their musical taste, 松尾-san prudently shapes the frequency response to be heavily bass-oriented, while keeping the transient characterstic as quick as possible.


This has been realized by utilizing a pair of huge closed-air ear pads, which effectively eliminates acoustic leak from its source, thus preserving the sub-bass response largely intact.

Sony MDR-XB700

Disclaimer: At last, the loan Danganronpa has generously provided is now completed. I sincerely send my gratitude to him.


According to the designer of XB series, 松尾伴大-san, this first generation of XB-series (XB300 to XB1000) is specifically tuned for club-goers, who are frequently exposed to fast-paced bassy dance music. In order to accommodate their musical taste, 松尾-san prudently shapes the frequency response to be heavily bass-oriented, while keeping the transient characterstic as quick as possible.


This has been realized by utilizing a pair of huge closed-air ear pads, which effectively eliminates acoustic leak from its source, thus preserving the sub-bass response largely intact.

A fundraiser for M.R.O

[Updated on 8/16/13: Since Paypal have deliberately taken down their donation widget, this is now a simple fundraiser for this blog.]


Ultrasone HFI-780 and S-Logic

Disclaimer: I am finally down to Danganronpa's second last pair!! Oh you have no idea how bad I wanted to talk about this manufacturer.. 


Ever since Ultrasone introduce their proprietary technology, S-Logic™, the legitimacy of their claim has been disputed quite heavily within the headphone enthusiast community.
"...In studying the past, it is clear that S-Logic is the only way to influence stereo or channel tone signals to produce a 3-dimensional auditory event without any digital, binaural processing..." from http://ukrtech.com/root/faqfileref/27049.pdf
According to the manufacturer, S-Logic™ is an acoustic passive filter that promotes a front-localized surround sound. In short, this is done by creating an accurately controlled acoustic passage through an opening at the bottom part of the front baffle, and the reflected sound wave originated from the port yields directional pinna notches along the frequency spectrum.

B&K 4128C's HRTF characteristic:  / 45° / 90° / 135°
Since conventional headphone auralization techniques, such as Focusrite VRM, Creative CMSS, WaveArts Panorama, or even ToneBoosters Isone involve with actively simulating a specific HRTF target acquired via different head & pinna models, Ultrasone's approach seems rather passive and dull, like that of a simple cross-feed network.

Thursday, August 15, 2013

AKG K702

Disclaimer: Yet again, this is Danganronpa's fourth pair. Now I only have two more to go..!

Along the history of headphones, AKG have continously made many technological innovations, such as K340, the ultimate electrostatic-dynamic hybrid, and K1000, which is driven like a pair of loudspeakers. AKG's reference headphones surely have a great heritage to carry on!

And K702 has two notable features: The first one is its bi-layered diaphragm, which is claimed to improve the high-frequency response characteristic, and the second one is a flat voice coil. Although the electroacoustic effect of a flat voice coil is not verifiable, AKG's patent, US6185809, states the diaphragm with variable thickness "significantly improves the vibration behavior of the diaphragm".


Westone UM3X

Disclaimer: This IEM was sent all the way from Singapore. Much appreciated, Nate! Measurement h as been carried out at the reference plane with a pair of small Westone mushroom tips. Unfortunately, it turned out his pair is faulty on the left.. :-/ Thus, only the electroacoustic performance of the right unit will be discussed in this analysis. 

I first auditioned this IEM at the CanJam 09, which was held in Los Angeles, California, along with Westone 3. As far as I can recall, my initial impression was just "OK" and UM3X was slightly more linear than Westone 3, at least to my ears.


And four years later, one of the regular visitors of my blog, Nate, sent in his pair for analysis with specific requests. And as always, I never turn down a friend's request ;)


Monday, August 12, 2013

Sennheiser HD280 PRO

Disclaimer: This is Danganronpa's third pair, and I still have three more to go after this. As I am trying to analyze everything as fast as I possibly can, please bear with me for just a few more weeks! :)


Sennheiser HD280 PRO is a closed-air/closed-back circumarual headphone, which is specifically made for a studio monitoring purpose. 

Sunday, August 11, 2013

Sennheiser Momentum

Disclaimer: This is another loan provided by my good friend, Danganronpa. I shall return his generosity with an accurate analysis! 


Dr. Axel Grell of Sennheiser holding a pair of Momentum
from http://www.aes.org/conferences/51/invited_speakers.cfm

Introduced in the late 2012, Sennheiser Momentum is a closed-air/closed back portable circumaural headphone featuring a real leather ear pad & sleek design. At the CES 2013, Dr. Axel Grell, the designer of Momentum, has mentioned:
"The sound is still sennheiser-like and the style meets the sound quality."
As Sennheiser have always been very truthful to their reference sound, which is a downward sloped diffuse-field response, it can be assumed that Momentum is accurately calibrated to match the target as well.


XTZ EarPhone-12 Part 1: Aesthetics



Introduction

EarPhone-12 is the very first IEM made by XTZ, an audio equipment manufacturer originated from Sweden. As their philosophy aims for a high price per performance ratio, the IEM shall reflect their value as well.


XTZ EarPhone-12 Part 2: General analysis + XTZ Player

Continued from Part 1, Aesthetics


XTZ EarPhone-12 is designed with an appropriate philosophy in mind:


IOW, unlike other random IEM companies, the manufacturer actually employees a conventional ear simulator for calibrating their products. As such practice is essential for making an accurate, high-quality headphones, it can be assumed that XTZ certainly know what they're doing.

And most importantly, in collaboration with Dirac, XTZ provide an iOS app dedicated for EarPhone-12. XTZ  According to the manufacturer, the app yields:

- An improved soundstage
- Clearer voices
- A tighter and deeper bass reproduction
- Improved timbre
- Perfect Balanced Sound

Since Dirac's HD technology has been proven to be very legit, a huge improvement in sound quality can be expected.


Saturday, August 10, 2013

SONY MDR-CD1700: The heir of the throne?

Disclaimer: I purchased this headphone in 2004 from an UK distributor. The model was already discontinued in 2000, so the price was £63 + shipping. Not a bad deal, I guess.



MDR-R10, also known as the king of headphones to SONY enthusiasts, debuts in 1988. And the economic downgraded version, MDR-CD3000, follows right after along with other introductory models. These are known as the first generation CD series. SONY have had a great success with the first generation, but none of the headphones really sound like R10; they are all too bright! And finally, in 1996, the second generation, starting with MDR-CD1700, equipped with 50 mm bio-cellulose & Vectran composite drivers, rocks the scene with its neutral tonality close to that of R10.


Friday, August 9, 2013

Sony MDR-CD780


from http://www.sonicstudios.com/mdr-f1.htm

It has been 10 years since the release of the last generation of Sony's CD-series headphones. While Sony MDR-CD2000 is featuring a Vectran-bio cellulose composite diaphragm, MDR-CD780 simply utilizes a PET diaphragm, while sharing most of the technical specifications with its sibling. Although CD-series mainly consists of a closed-air/closed-back design, this generation adapts a radical open-air/open-back configuration, like that of MDR-F1, for better airiness, but with more isolation and comfort.


Tuesday, August 6, 2013

Sennheiser HD650




Sennheiser HD650 has been known for its deep bass and neutral tonal balance ever since its release. After 12-consecutive-years of dominance, does this headphone still have a chance against new-bloods?

Stax SR-207: Back to the basic

Disclaimer: This unit has been generously provided by my good friend, Danganronpa. And this is what I call a Southern hospitality, thank you very much! In order to minimize the linear error in the low frequency range, measurement has been carried out with acoustic leak minimized, by using a silicone putty as a sealant.


Although SR-207 is STAX's cheapest entry model, it is still a part of SR-Lambda series, which has a great heritage and legacy in the history of headphones. And since all of the current Lambda series models from SR-207 to SR-507 share very similar technical specifications, this entry model indeed deserves a good look as well.

Sunday, August 4, 2013

On the modification of Sony MDR-1R: It's as easy as ABC


Several months ago, a friend of mine asked me to see if there is a chance of modification with Sony MDR-1R. So here I am at it. The goal of this modification is to be quick, simple, and reversible, while taming the mid-bass range effectively. All you need here is a scissor, a masking(duct) tape, and a screw driver! (And preferably some foam pads with various density)


Wednesday, July 31, 2013

The effect of ear sleeves: TDK BA200

Disclaimer: Measurement has been carried out at the reference plane.

Thanks to its high acoustic output impedance, TDK BA200 is very susceptible to bore resonance induced acoustic interaction. Upon assessing the acoustic effect of various types ear sleeves, the optimum setting for BA200 shall be discovered.

Aurisonics ASG-2

Disclaimer: I thank the owner, UnityIsPower, for letting me analyze his precious gear. Measurement has been made with the bass-tuner set at its minimum.


Aurisonics ASG-2 is a hybrid IEM, featuring a dual-driver balanced armature tweeter and a ⌀15 mm dynamic woofer, just like T-PEOS H-200. Moreover, the IEM has an adjustable bass-tuner on its faceplate. According to eke2k6's review, this IEM doesn't have a passive crossover network implemented in order to avoid any kind of unnecessary complication arising from electric impedance interaction.

Now that's quite a bold move, considering the fact that three transducers are coupled together.. And since Mr. Dale Lott, the founder of Aurisonics, claims ASG-2 is tuned with their reference sound signature but treble further enhanced, the hope is higher than ever! But then again, one of my visitors says:


Oh..


Sunday, July 28, 2013

DBV#3 modified T50RP by BMF

Disclaimer: This loan has been arranged by Rick, who is a regular visitor of this blog. I truly appreciate your support, my friend! Will return the headphone back to you promptly.

BlueFlyerMonkey, the creator of this modification, keeps record of his efforts on this thread at Head-Fi.org as an open-source database. I send my sincere respect to him for his continuous devotion. BFM describes the sound of DBV #3:
Sub-bass and bass are deep, musical, and textured. Bass does not bleed into the midrange or mask the treble range. Midrange is clear, lush, and properly placed. Treble extension and clarity are improved over DBV #1. Imaging is very good. These headphones are Fast.  


Saturday, July 20, 2013

HiFiMAN RE-600 Part.2: General analysis - Songbird

Disclaimer: This IEM is owned by James. Measurement has been carried out at approximately 3 mm away from the reference plane, using a pair of stock bi-flange sleeves.





After a sudden discontinuation of their introductory model RE-0, HiFiMAN comes up with a new pair of IEMs, RE-400 Waterline, with a price tag of $99. And in order to reinforce their high end IEM line up, RE-262/272 are replaced with RE-600 Songbird. As HiFiMAN RE-262/272 have stunning electroacoustic characteristics, if RE-600 turns out to be as good, or even better, it will surely be considered as a very successful transition done by the manufacturer.


HiFiMAN RE-600 Part.1: Aesthetics




Introduction

HiFiMAN, which is Head-Direct's own brand, is well-known for manufacturing IEMs with solid electroacoustic performance. And this has proven to be true every time their IEMs are analyzed here. The recent model, RE-400, is somewhat of a disappointment to me personally, but the sound itself is fine nonetheless. Thus, several weeks ago, I asked the representative of HiFiMAN for a demo sample of this new product. However, it seems the request has never reached to the founder, Dr. Fang Bian. Perhaps there was a communication error between the reps? I am not sure.. So, as always, one of my good contributors, James, hooked me up with a brand-new pair. I can't believe it.. Thanks again, James!

Brookstone Clear JI-280Z (Radius HP-TWF22) + Ne AUDIO


Beats by Dre Powerbeats, Brookstone Clear Dual-Drive JI-280Z, and Radius HP-TWF22 share one common feature: A double driver with the exact same specification.

Manufacturered by a well-known ODM company in Asia, this driver, also known as Double Driver Matrix, is a coaxial dynamic microtransducer with a ø7mm tweeter and a ø15mm woofer joined together by a crossover network on a same yolk. However, their magnetic systems, voice coils, and acoustic outputs are all separated in order to prevent any type of acoustic interference among the drivers from occurring. And by inverting the polarity of one of the magnets, both drivers remain in-phase with one another.


And in conjunction with an Italian DSP solution provider, Dirac, Radius comes up with a proprietary iOS application, Ne AUDIO, in order to further increase the fidelity of the IEM. According to the manufacturer, Ne AUDIO not only corrects the overall frequency response , but also helps damp any unwanted transient characteristic of the driver itself. Really?


Sunday, July 14, 2013

Ultimate Ears Triple.Fi Reference Monitors: Modified by Rin Choi


A $990 vs $99 Challenge



About a month ago, a parcel originated from Changstar was dropped off at my doorstep. I was afraid it was a fart bomb(My apologies to the folks at Changstar, LOL) or something, but thankfully, it was a scratch pair of Ultimate Ears Triple.Fi 10 Pro, sent to me for modification from James. Previously, I stated:
"Is it just me, or the frequency response of the UERM really resembles that of good old Triple.Fi 10 Pro?"
So I set out to find out whether TF10 can be modified to closely match the frequency response of UERM or not to fulfill my friend's request. And if possible, the modified TFRM will be sent off for user auditioning, along with the IEM it was modeled after, UERM itself.

Ultimate Ears Universal In-Ear Reference Monitors

Disclaimer: This special version of Ultimate Ears Reference Monitors has been provided by James. My blog would've been long gone without my friends' continuous support, THANK YOU!

In a collaboration with Capitol Studios, Ultimate Ears developed this custom IEM for studio engineers. The manufacturers claim that the IEM has been meticulously tuned to be flat, in order to match any type of professional recording/mixing/mastering conditions.


Thursday, July 11, 2013

Samsung HS330



Originally designed by Young-Bo Electronics of South Korea as a stock IEM for Galaxy S 4, HS330 is Samsung's counter-blow to LG's hugely successful IEM, HSS-F450 aka Quadbeat, which is bundled with their Optimus G.



In order to overwhelm their competitor's sound quality, these South Koreans start to talk about boldness: They double the number of transducers, by coupling a ∅8 mm tweeter to a ∅10 mm woofer via a crossover network split at 4 kHz. Moreover, various acoustic tweaks have been utilized here in order to increase the overall fidelity.

First, a slit is created at the nozzle. This effectively relieves the air pressure built up in the ear canal, thus yielding airiness.

Second, two acoustic vents optimize the tonal balance of the IEM, by equalizing the air pressure deviation between the frontal cavity and the rear cavity.

And by further investigating into the document that the developer, Young-Bo Electronics, have provided, a deeper look into the double driver's working principle can be taken. Above diagram excerpted from the document suggests two drivers are acoustically well-insulated, removing the possibility of any ill effects caused by phase cancellation. However, as the rear driver is completely inverted, a good care must be taken during the manufacturing process in order to prevent polarity inversion of the entire frequency spectrum.

Monday, July 8, 2013

T-PEOS H-200

Disclaimer: As always, I can't possibly thank enough Flysweep, for providing me with this opportunity. I'd like to express my sincere gratitude to you, my friend. And of course, Inks takes credit for arranging the loan.


After the commercial success of H-100, T-PEOS takes another spin on their BA-Dynamic hybrid technology. Now featuring a dual balanced-armature driver as a tweeter, H-200 is claimed to be the next-generation hybrid IEM.



Surprisingly, unlike its predecessor, H-100, H-200 does not come with a performance certification chart provided by Goldenears.net. It is a well-known fact that the partnership between T-PEOS and Goldenears has been put to halt simply because the performance of the IEM can't be guaranteed; the manufacturer have been constantly changing the sound tuning of H-100, even after the IEM is certified.