iFi Audio GO Bar Kensei

iFi currently produces three portable USB DAC dongles. The entry level, iFi Go link, the regular sized iFi Go bar and its limited edition, the iFi Go bar/Gold edition which is now sold out. The brand new addition to the family is the iFi Go bar Kensei which incorporates all the extra technical features that were to be found in the Gold edition plus a few more.



Technical stuff

The DAC section of the GO bar Kensei uses a powerful 16-core XMOS micro controller to process the audio data received at the USB input and ensure a perfect partnership with the 32-bit Cirrus Logic DAC chipset. A customized digital filter minimizes pre-echoes and ringing artifacts and a Global Master Timing precision clock system ensures ultra-low jitter. The iFi Go bar Kensei supports PCM up to 32-bit/384kHz, native DSD playback up to DSD256, 2x DXD and full MQA decoding.

The analogue circuitry features a balanced design with a symmetrical twin-channel output stage. This topology, usually reserved for larger and more expensive amplifiers owing to its cost and complexity, reduces noise and crosstalk in the signal path by fully separating the left and right channels.



New features

The Go bar Kensei employs enhanced power supply and clock circuitry compared to the original Go bar. The Gold edition also featured an enhanced power supply but iFi doesn't specify the differences between it and the Kensei. By closely inspecting the circuit boards we can see one capacitor in the Go bar, three on the Kensei and four on the Gold edition. I don't know the exact values of the capacitors but the Gold edition seems to have higher rectifying capacitance.



K2HD technology

The brand new and shout after feature of the iFi Go bar Kensei is the implementation of the K2HD processing technology that is an algorithm that revives rich, natural harmonics into emotionally flat and lifeless digital recordings.

The unparalleled originality of K2HD lies in its advanced high-frequency extension, enabling the restoration of natural harmonics and overtones beyond 22kHz, delivering audio quality that is close to the original master.

The K2HD technology was originally developed by engineers at the Victor Studio who noticed a lack of emotion between their original masters and digital sub-masters, sparking a quest for a solution. The K2 parameter values provided by iFi for the Go bar Kensei are completely new K2 parameter values that have never been used before and were selected by JVC/KENWOOD and passed a listening test by studio engineers at Victor Studios.

You can enable the K2HD processing technology by long pressing and holding the setup button for 3s. After the MQA LED starts to flash, then press the volume(+) button and the K2HD LED will light up to indicate that it is active.

The K2HD mode is only effective when the audio file format is PCM and the sampling frequency
needs to be ≤192kHz. The K2HD mode is invalid and cannot be enabled when the audio file format is DSD or MQA. The K2HD is compatible with the GTO filter but its upsampling frequency will be limited to 192kHz instead of 384kHz.



Extra features

The Go bar Kensei incorporates iFi’s iEMatch technology for use with high sensitivity IEMs and a Turbo mode (high gain) for power hungry headphones. The iEMatch is effective for both the 3.5mm and 4.4mm outputs, selectable by a micro switch at the side of the chassis. The high gain is enabled by simultaneously pressing the volume + and - buttons. The 3.5mm output additionally features iFi's S-Balanced technology that cuts crosstalk and noise by 50% compared to regular single ended outputs. Standard are also iFi's renowned XBass+ and XSpace analog processing modes that enhance bass and soundstage perception. These two modes can be separately or simultaneously active.



Non Audio stuff

The chassis of GO Bar Kensei is crafted with Japanese stainless steel for maximum rigidity and shielding from EMI. The surfaces have a matte polish that is not too shiny so it doesn't attract fingerprints. The iFi and Kensei logos are engraved at the front surface, furthermore all other markings that indicate the various operations are also engraved and not ink printed. Craftsmanship and finish are of the highest quality, the iFi Go bar Kensei is one of the best made USB DAC dongles in the market. Subjectively speaking, the Kensei is by far better looking than the Go bar and Go bar Gold edition and maybe the most beautiful and premium looking portable USB stick among all the competition.

The size is compact enough (65 x 22 x 13.2 mm), the iFi Go bar Kensei is not bigger or larger than similar products, but it is substantially heavier. It weighs a whole 65.5g when the iFi Go bar is 28.5g. So while it is pocket friendly and small sized, it is not the best idea to leave it hanging out from your smartphone.

Accessories

The iFi Go bar Kensei comes packed in a nicely crafted wooden box together with a leather carrying case, two short USB type-C to C and USB type-C to lightning cables plus a USB adapter.



Power output and efficiency

The rated power output of the Go bar Kensei is 475mW/32Ω or 7.2V/600Ω from its balanced output and 300mW/32Ω or 3.8V/600Ω from the unbalanced, the same as with the iFi Go bar. This is amongst the most powerful USB DAC dongles that can drive full sized headphones like the Meze Liric 2, the Sennheiser HD660S2 and the Focal Clear Mg. The Kensei is also suitable for use with sensitive earphones because it is silent enough and you also have the option to enable the iEMatch and kill any hint of background noise.

The power consumption of the iFi Go bar Kensei was measured at 0.12A/0.63W when idling and about 0.16A/0.81W with the Meze Liric 2 playing high resolution material at a pretty loud volume. This is not the most efficient USB dongle that you can buy but it also doesn't consume more power than similarly power hungry dongles like the Cayin RU-7 (0.18A/0.92W).

Audio stuff

The iFi Go bar Kensei has an excellent sonic performance that positions it among the top specimens of its kind. It outperforms the iFi Go bar with sonic qualities that match that of the Go bar Gold edition which is already one the best sounding dongles in the market. They do sound a little bit different of course but this is something that is going to be discussed later on.

The Kensei is exceptionally musical and engaging with a sound signature that combines an analog-like and organic timbre with top notch technicalities. Even with the K2HD mode disabled, the sound of the Kensei is realistic and lifelike without any significant digital glare. Sometimes the treble can be perceived as a little fake but this is something that completely vanishes after enabling the K2HD mode. The effects are subtle but worthwhile, consider them as the perfect icing on the cake. The K2HD mode really reinstates and adds all the natural harmonics that were previously missing from the higher frequencies. The result is an expressive and realistic sound with unparalleled fluidity, full of vibrant harmonics and colorful overtones. The Kensei sounds like a miniaturized analog set-up, this is the kind of source that will make your music sound rich and full of emotions. Please note that not all audio tracks will benefit from the K2HD processing technology, sometimes I couldn't notice any audible differences with or without the K2HD.

Technicalities are stellar, the iFi Go bar Kensei is crystal clear and transparent with excellent definition and precision. It can produce deep and layered bass which is tight and controlled with huge physical impact. Dynamic and highly contrasted it can make all earphones come alive and follow the most instantaneous and sudden dynamic changes. Resolution and refinement are among the best ever heard while the Kensei is very skilful at reproducing the finest micro details without never sounding analytical or mechanical. Truth is that some of the competition, and not necessarily more expensive, can sound a little more transparent and crystalline with better precision and deeper detail extraction but they usually tend to become a little sterile and clinical, something that never happens with the Kensei.

The soundstage of the Kensei is not only spacious and expansive with good positioning accuracy but it is also exceptionally holographic and immersive. The Kensei really excels in the way that it communicates spades of ambient information thus contributing greatly to the overall realism. The Kensei will make your earphones sound like ear-speakers and is one of my top recommendations for listening to classical music.



Internal affairs

The iFi Go bar Kensei is not only the most beautiful looking member of the family but also the best sounding one. The Kensei is better than the Go bar as it surpasses it in transparency and clarity, it has an improved suit of technicalities and much better timbre thus creating a more lifelike listening experience. When it comes to the Go bar Gold edition, they are in the same league without a clear winner, the differences are rather a matter of taste than actual performance deviations. The Gold bar has a warmer and slightly thicker sound signature with a bit more visceral and weightier bass but the Kensei is more transparent, has better clarity and definition while it sounds more controlled and tight. The Gold edition has an already natural and organic timbre but the K2HD further enhances these qualities, especially in the critical higher frequencies that sound less digital and more resolving.

Comparison with the Cayin RU-7

This is really a difficult comparison as both sound more alike than different. They are two of the best (if not the best) USB DAC dongles you can buy if you care about timbre realism and tonal accuracy. To my ears, the Cayin RU-7 is a little more natural sounding with just a bit better sense of overall realism and soundstage holography. Differences are really subtle and I could happily own one of those as my end game USB DAC dongle. They both earn my highest recommendation and someone should consider other, non audio, differences in order to decide which one to get. The iFi Go bar Kensei has more bells and whistles that allow for a more personalized listening experience but the Cayin RU-7 has a real, unamplified, line output (both 4.4mm and 3.5mn) so you can use it as a miniature 1-bit DSD DAC.

Conclusion

The iFi Go bar Kensei is not only an improvement over the regular Go bar but it even surpasses the limited Gold edition, depending on someone's listening tastes. The Kensei is a bit expensive but not without a reason as it offers class leading sonic performance and plenty of features. Actually, the Kensei is one of the best sounding USB DAC dongles in the market, thus earning the “Kensei” honorary title.

The price of the iFi Go bar Kensei is €449 and you can buy it from all authorized dealers around the world.

The review sample was kindly provided as a long term loan.

The GO Bar Kensei is a portable DAC (digital-to-analog converter) it is designed to offer more power and clarity when compared to the stock output. My thanks for ifi lending a review unit.

Design and Build Quality:
The GO Bar Kensei is meticulously crafted, akin to a legendary sword forged for a Kensei (Kensei (Japanese: 剣聖, sometimes rendered in English as Kensai, Ken Sai, Kensei, or Kenshei) is a Japanese honorary title given to a warrior of legendary skill in swordsmanship. The literal translation of kensei is "sword saint".)

The Kensei is the heaviest dongle and size wise it's one of the biggest I've used but it's not unmanageable.
The GO Bar Kensei is the first Dongle-DAC to feature the renowned K2HD technology. K2HD enhances audio quality significantly and is a game changer in my opinion.
Power Supply and Clock Circuitry: Improved power supply and clock circuitry contribute to superior sonic performance. The Kensei surpasses the original GO Bar in audio quality, thanks to an enhanced clock and a more powerful 477mW power supply.
The GoBar Kensei offers a range of filters to tailor the sound to your preference giving the dongle a wide range of customization with features like IEMatch, Xbass, and Xspace. The price of this Dongle is high when compared to the competition like the original or the questyle M15

Sound opinions:
The ifi GoBar Kensei is a large improvement over the OG and many of its competitors. It has a big sound, everything I put on it sounds better, larger, and clearer.

In conclusion, if you’re looking for a high-quality, portable DAC that delivers exceptional sound, and features the iFi Audio GO Bar Kensei is worth considering. It's made extremely well, sounds amazing and the only cons are the weight and cost.

Introduction

I don’t think iFi-Audio need much introduction on head-fi anymore, over the last few years they have amassed an array of products covering almost every need you could need for your music and headphones, all bar a DAP!

I’ve liked and owned a few of their products, like a lot of products I own, I don’t always keep things a long time bar a few longer term items that just stay in my cycle. The original Go bar’s fall into that category for me. I owned both the standard first edition and the limited edition Gold Go bar.

In my quest to find the ideal portable solution for my needs I sold my Gold Go bar when I bought the iFi Go Pods (wireless adaptors) thinking I was done with dongles. A few months on and as much as I love my Go pods I found myself still trying new dongles. This led me here to trying the new Go Kensei bar.

Disclaimer

iFi-Audio provided me this unit to review and return when finished or choose to buy. This was/is not a gift



Unboxing/Packaging

Usually with all of the other iFi products I’ve owned the packaging is pretty standard, nice enough but functional boxes with all the cables and adaptors that you will need to get listening. The Kensei is the exception, as well as the normal packaging it also comes in really nice engraved wooden box. The quality of this box is really good and is a nice touch.





Design and Features

Detailed tech specs are on this showcase page as well on the iFi page so I won’t go into them here


iFi-Audio make some really well designed products that are on the whole easy to use and the Kensei is no different.

The size is just right for a USB-C Dongle, it is a lot smaller than you think it is going to be. It is very weighty which I’m fine with as it adds to the overall feeling of a high quality product. The Kensei is a slab of solid steel which feels very sturdy. Some nice Japanese engraving on the steel body.

Side of the Kensei has a function button along with volume up and down buttons. There is also a selector for the inbuilt IEMatch. I don’t personally have any really sensitive IEM’s that require the use of this but it’s nice feature to have included.

3.5mm single ended and 4.4mm balanced earphone connections adorn the bottom of the Kensei. On the back of the Kensei is a row of small LED’s which indicate various functions.

Overall this looks, feels and functions like a premium product should.





The Kensei features a list of different filters to allow the listener to adjust sound, however I tend to use the filter that keeps what is a fairly neutral profile. I did listen with the other filters and they all make very small subtle differences, none are detrimental to the sound.

The biggest factor that iFi have emphasised for the Kensei has been the inclusion of JVC’s K2HD technology, from what I can understand this a processing feature that JVC say enhances the sound of a recording. It is not a new format but merely a process. It seems to have been around for over a decade and was used for a period of time in the mastering of some CD releases. I tried it and will comment on how I found it.

In addition to this there is the Xbass and Xspace. Xbass is designed to add some low level thump to the bass response and Xspace to open up the sound. Lastly there is the Turbo mode which is essentially a high gain mode




Gear used

For testing I used the following

Earphones

Sony IER Z1R

Fir Audio Rn6

Custom Art FIBAE 5

Headphones

Sennhieser HD660s

Grado RS1X


Source was my Samsung S24 Ultra smartphone using a mixture of streaming from Tidal and Qobuz and the UAPP app. Battery drain considering the power that this dongle can achieve is quite impressive. I listen for maybe an hour to two at a time and notice my battery life take a small hit but nothing that worries me too much.

Selecting the filters and sound enhancements are easy to do with a press of the function for 1-3 seconds and a press of the volume button dependant on usage, not having a screen is really no issue with the Kensei or any of the Go bars.



Sound

The majority of my listening was with the earphones listed above with some light headphone use. I tend to use a set playlist of certain songs that I always use when trying new gear. Most of my music taste is of an indie/alternative nature but do also like some electronic music.


Although I tried the different filters and found very minimal subtle differences I used the ‘BP’ Cyan filter for most listening which is the bit-perfect most neutral filter on the Kensei

In addition for most listening the 4.4mm balanced connection was used.


Fir Audio Radeon 6 (Rn6) – These earphones are probably the best earphone I have owned and when using with my normal DAP/Amp combo of Cayin N7/C9 they are just simply stunning with very little that seems to compete. So I was keen to see how the Kensei would fare as the Hip DAC 3 fared well when I tested that a few months ago.

First thing of note was that the bass rumble on the Rn6 was still very evident with the Kensei, and the mids were still majestic, detail in the highs was also presented extremely well. The Kensei and Rn6 played through my playlist of Bowie, The Smiths and others with ease, producing excellent results. The Cirrus Logic DAC chipset retains what I always consider to be the iFi ‘house sound’ which is to my ears, neutral yet detailed and warm without you ever really thinking it too much of either (really hope that makes sense!).

On most tracks that I tried with the Rn6/Kensei combo, the ability of the Kensei to get very close to the N7 in terms of detail and smoothness is not be underplayed.

The same applies to the Sony IER Z1r, this earphone needs no introduction, an absolute classic that sometimes splits opinion. I was late to the party with the z1r, only getting them a few months ago used but they were worth the wait. Even after a few years they are rarely bettered (in my opinion) and produce a wonderful sound, which is even better when powered well. I wondered if the Kensei could provide that power and it does, needs quite a few notches over the Rn6 on the volume but the depth it gives is really good.

It’s a similar tale with the Custom Art FIBAE 5 and their dual planar drivers, on paper they shouldn’t need much power but they benefit from it and again the Kensei doesn’t disappoint.

The output power of 477mw through balanced is very impressive for this kind of dongle that takes it power from your USB-C device. Most that I have tried have been around the 230-300mw output power.

Xbass when I tried it does add a little low end into the mix and it feels well implemented but none of my earphones really need it so I didn’t really use it.


K2HD

What is it and what does it do?

I’m not going to lie and say that I knew what this was before and I’m not going to go into any kind of explanation as I won’t do it justice so here’s the link that iFi provide

https://ifi-audio.com/wp-content/uploads/2024/03/iFi_GO_bar_Kensei_K2HD_Tech_Note_2024_Mar.pdf

Does it work?

I’m going to say that for the most part it does seem to make a positive difference. I’m not normally one for using different enhancement options, I barely ever use Xspace or Xbass and haven’t really used anything in the past.

With the K2HD I used my normal test tracks along with a few others to see if I could hear a difference and I think that I did, and in a positive way. Notes felt a little more rounded and on some tracks there was more depth to the music, an example being a little more echo to the snare drum in the first minute or so of ‘I Know It’s Over’ by The Smiths. The drum is isolated slightly and the timbre/echo/depth seems better. I’d say the bass response on most tracks is also marginally more rounded. The one aspect that surprised me was that most of the tracks felt smoother with more of a natural feel however this is only to my ears and others might not experience the same.

I noticed small differences like this across most tracks and find myself having it turned on all the time.





Closing thoughts

Normally I would do some comparisons either from gear I still have or from notes on previous equipment.

This time I’ll just say that this is the best dongle I’ve tried to date, I can’t compare to the Gold Go but from memory and some notes I wrote they are much the same. I’ve tried a fair few dongles over the last 2-3 years and this one is by far (for me and my usage) the best I’ve used. It gets close to my main DAP at times but doesn’t surpass my Cayin N7 but I wouldn’t expect it to given they are different devices however if I had to give up a DAP and just have a dongle, the Kensei would be more than sufficient for my needs.

thaslaya's star rating system:
☆☆☆☆☆ - Fantastic!
☆☆☆☆ - Recommended
☆☆☆ - There are buyers but not for me
☆☆ - Can't see the appeal
☆ - Product is a failure

Disclaimer:
This product was provided to me by iFi Audio in exchange for my impartial and honest review. I recieve no compensation and all thoughts and opinions are my own. A special thanks to Karina at iFi for coordinating this unit for review.

Gear used:
● LG v30+
● Samsung Galaxy s22 Ultra
● Samsung dongle
● Various iems

Source:
● Listening was done through Amazon Music HD or Ultra HD.

Introduction:
Honestly iFi Audio needs little introduction for those in the audiophile community and, if you're looking to purchase the GO bar Kensei, chances are you're familiar with the brand. The Kensei is the third iteration of the GO bar dongle DAC/amplifier. The previous being the original GO bar and the 10th Anniversary gold edition. Kensei is a Japanese word that translates to "sword saint" - an honorary title bestowed on very few warriors who displayed legendary swordmanship. It's a catchy name for sure but does the newest model of the GO bar live up to it's namesake? A question I hope to answer in this review.

Unboxing:
The packaging isn't much different than other iFi products but once the outer box is open there is a nice surprise waiting. The Kensei comes in a beautifully engraved wooden box. It's a work of art in and of itself and makes a nice display piece to place on a shelf. Included with the usual paperwork and user manuals are both a USB-C and lightning cables. Also there's a small USB adapter for use with desktop setups. It's simple to include all the connections one could need but it's always appreciated as some companies make you choose between cable types when ordering.

Design:
I have seen pictures of the GO bar many times in listings on Head-fi and Reddit. I always assumed its length to be much longer so I was taken aback when I opened the box to find how little it really is. It's surprisingly small but very dense and much heavier than anticipated. Don't let it's size fool you though, this thing is an audiophile's dream tool whose size undercuts its power, not unlike the samurai swords of old. Made from Japanese stainless steel, the Kensei is sturdy, robust and lustrous. The build quality is absolutely superb. It feels great to hold in hand and premium to the touch. The only drawback may be the finish is a bit prone to fingerprints and scratches. On one end of the unit you'll find the USB-C connection and on the other are the 3.5mm and 4.4mm ports. Located on the side of the Kensei are the function button, + and - volume buttons, and the IEMatch toggle. On the back are a plethora of indicator lights to show the playback format and the current options being utilized.

Technical Information:
The Kensei utilizes a 32-bit Cirrus Logic DAC chipset. It supports the following audio formats: PCM up to 32-bit/384 kHz, native DSD playback up to DSD256, 2x DXD, and full MQA decoding. I'm not a very tech savvy user so I will have to differ to iFi's website for all that mumbo jumbo. A full rundown of the internals and circuitry can be found here.


Features:
The list of features on the Kensei is very impressive, especially when you consider there's no companion app. There is, of course, iFi's staple XBass and XSpace. There's also a Turbo mode, essentially a high gain level, and 4 digital filters to toggle through that I'll touch on later. Specific to the Kensei version of the GO bar is the new K2HD mode that, according to iFi, "revives rich, natural harmonics into digital sound, adding an organic quality unlike any other". It essentially aims to make your music sound a bit less digital and more lifelike.

Power consumption:
With great power comes great...battery drain? I don't think that's quite right but in the case of the Kensei it's close. This thing does indeed drain your source's battery fairly quickly but it also depends on what options are enabled at the time. When using higher volumes, XBass, XSpace, and Turbo mode, the power consumption will be higher. My LG v30+ was only able to last about 2-3 hours of continuous use. My S22 Ultra faired better at around 4-5 hours but I was also browsing and utilizing other functions of the phone.

Sound impressions:
I don't know what magic is going on inside the Kensei but it elevates everything I've paired it with to another level. There's enough variety with the plethora of options that makes using any iem/headphone an easy and fun interaction. The 4 filter options are Bit- Perfect (cyan), Standard (red), Minimum Phase (yellow), and Gibbs Transient-Optimized or GTO (white). My filter of choice varied with each iem depending on the synergy. It's a bit hard to explain the subtleties that accompany each filter and compare them to each other. I believe the best way to convey what I hear is to share what settings I used with each individual pairing and how it affects the sound compared to the stock tuning.

●Aful MagicOne - Standard (red) filter, K2HD enabled, 4.4 connection with IEMatch, Turbo mode, and XBass and XSpace enabled. This added a touch of warmth to the vocals but still allowed them to shine. It also opened up the soundstage and added some much needed bass emphasis.

●Kiwi Ears x Crinacle: Singolo - Bit-Perfect (cyan) filter, 4.4 conncection with IEMatch, Turbo mode, and XSpace enabled. This added more vocal presence while preserving the excellent timbre of the mids, more tightness and speed to the bass, and an enhanced soundstage.

●Softears Volume - GTO (white) filter, 4.4 connection with IEMatch, Turbo mode, and K2HD enabled. There's a bigger midbass slam and texture, vocals had a slightly more organic timbre, and the entirety of the frequencies had more energy without any troublesome peaks.

●Truthear x Crinacle Zero:Red - Minimum Phase (yellow) filter, 4.4 connection with IEMatch, Turbo mode, K2HD, and XBass enabled. There's a deeper subbass rumble and presence bordering on basshead levels but overall the bass had more separation with no bleed. The overall warmer tuning was still present but vocals and mids had more clarity and were presented more forward on the stage.

●Accoustune HS1790ti - Bit-Perfect (cyan) filter, 3.5 connection with IEMatch, K2HD, and XBass enabled. The bass sounded more full with a bigger rumble, vocals were slightly more forward with a warmer organic tilt, and the upper mids/lower treble had better separation and overall better dynamics with more energy.

Final thoughts:
Honestly, this was an arduous review to get through. Not because I didn't like the Kensei. It's quite the opposite actually, I thoroughly enjoyed every moment! Reviewing was difficult because I found myself getting lost in the music due to the superb sound quality. I often felt drawn to hold the Kensei, relishing the weight and excellent build quality. Also somewhere deep in my subconscious I knew that with every word I typed I was closer to having to return the unit to iFi (maybe I should have drawn this one out a few weeks ). I have been a fan of iFi since I first tried the original hip dac. I'm now a full on disciple at the feet of the Kensei. Yes the price is high but the quality is absolutely there and in spades. The 4 distinct filters, K2HD, Xbass, XSpace, Turbo mode, and IEMatch all somehow add up to something that is more than the sum of their parts. I understand that a lot of consumers will probably never consider spending $450 for a dongle DAC. However, for those that can afford the cost of entry, the iFi GO bar Kensei is one of the finest products I've had the pleasure of using and easily the best portable DAC that I've come across. In my opinion, it has cemented it's legendary status and earned the moniker of "sword saint".