iFi GO Bar Kensei ($449): There are Dongles, and then there are Dongles.

Pros:

iFi build quality
Sound offerings available from the IEMatch, XBass+ & 3D
Really cool box
Sound can be tailored to your delight
Multiple accessories (as usual)

Cons:

Expensive
Fingerprint monger

iFi GO Bar Kensei ($449):There are Dongles, and then there are Dongles.

GO Bar Kensei

Intro:

The original GO bar was lauded for excellent performance and features, which many others did not have. It was also fairly expensive compared to some competitors, which also performed favorably to it in comparison. While not the costliest, the GO bar Kensei can be placed in that vaunted group of upper-end dongles such as the Cayin RU6, RU7, and Questyle M12 & M15. All are excellent dongles, with many functioning nearly on par with their desktop brethren.

Here is where the GO bar Kensei may separate itself because while it does share some with the family, it goes its way on its own merits. iFi is known for utilizing technologies outside the “normal” portable audio world, and the Kensei is no exception. Here they use technology developed in concert with JVC/Kenwood bringing something unique into play.

I am a fan of iFi products, having tested and owned many including my TOTL Pro iDSD/iCAN models as my go-to home baseline. This will not hinder my review, and it may even make me more critical of the unit, since I own many of their products and have a certain level of expectations going in. The Kensei is a loaner unit and will be returned upon the finishing of this review.

Specs:

Input		USB-C
Formats	PCM	44.1/48/88.2/96/176.4/192/352.8/384kHz
	DSD	2.8/3.1/5.6/6.1/11.3/12.3MHz
	DXD	352.8/384kHz
	MQA	Full Decoder
DAC		Bit-Perfect DSD & DXD DAC by Cirrus Logic
Headphone Output		BAL 4.4mm/S-BAL 3.5mm
Output Power (RMS)	Balanced	477mW@32Ω; 7.2V@600Ω
	S-Bal	300mW@32Ω; 3.8V@600Ω
Output Impedance		≤1Ω (≤3.6 Ω with iEMatch engaged)
SNR		132dB(A) / 121dB(A) (BAL/S-BAL)* 114dB(A) / 114dB(A) (BAL/S-BAL)
DNR		108dB(A) / 109dB(A) (BAL/S-BAL)
THD+N	Balanced	≤0.0025% (600Ω 2V) @ (20-20KHz)
	S-Bal	≤0.009% (16Ω 1.27V) @ (20-20KHz)
Frequency Response		20Hz – 70kHz (-3dB)
Power Consumption		<4W max.
Dimensions		65 x 22 x 13.2 mm (2.6″ x 0.9″ x 0.5”)
Weight		65.5g (2.3 oz)
Warranty Period		12 months
*With Intelligent muting activated

In The Box:


GO bar Kensei
USB-C to USB-C cable-10cm
USB-C to Lightning cable-10cm
Carrying pouch
Owner’s manual
USB-C to USB-A adapter
iFi warranty card

Gear Used/Compared:

iPhone 13 Pro Max
MBP
HiBy R4

Spirit Torino Twin Pulse IEM
CFA Solaris 2020
Meze 99Classics

Cayin RU6
Cayin RU7
Questyle M15

Tech Highlights:

The Kensei comes with the usual aspects associated with quality dongles/DACs, but also carries some tricks up its sleeve. First and foremost, the Kensei uses K2HD technology developed by JVC/Kenwood and modified to fit iFi’s needs over 18 months of collaborative work.

In a nutshell, K2HD seeks to restore what has been lost from the original masters when copying to digital representations. Purportedly harmonics and emotive effects are lost over numerous iterations from the original masters (this is why first pressings sound better than subsequent vinyl representations). Reviving that loss leads to a more organic, rich signature of the music revitalizing what the studio sound was meant to be when we hear the recordings. This iteration is a new version developed specifically for the Kensei and iFi.

The Bit-perfect 32-bit DAC chip developed by Cirrus Logic is capable of PCM up to 32bit/384kHx & DSD up to DSD256. The Kensei also supports 2x DXD and full MQA decoding.

The 16-core XMOS microcontroller offers support for the inbound sound also optimizing sound quality. With GMT (Global Master Timing) clock system for low jitter and the choice of four bespoke digital filters (GTO-my favorite on my Pro set), Bit-Perfect, Minimum Phase, and Standard) and two analog processing modes, the Kensei comes fit for use.

Throw in the usual iFi characteristics of Turbo mode (IEM Match off), XBass+, IEM Match (3.5mm se & 4.4mm bal), and XSpace and you have a highly tunable dongle.

Design:

Dongle/DACs are by nature small and mostly unobtrusive. The Kensei is no different, except for the look and heft. This is not a light dongle by comparison, and much of that can be attributed to the stainless-steel shell, which carries the bulk of the 65.5g weight. It also carries fingerprints. Coming in at 65x22x13.2mm it is slightly thicker than the Cayin RU7, but markedly heavier by almost 3x.

Carrying the Kensei script logo on one side, the other is side is all business with the nomenclature for all of the decoding choices and color LEDs, along with XBass+ & XSpace. The right side (as you look at the side with the LEDs) carries the function button on the top portion, which controls turning XBass+, XSpace, and actuating MQA on (long press). Below that are the volume up and down buttons, with the IEMatch toggle below that.

iFi has long held that a bit of fine-tuning could help with your jack of choice, and this is where IEMatch comes in. Switching to 3.5mm allows a synergistic approach with those headphones and IEMs that have a 3.5mm jack. Conversely, the 4.4mm bal does the same thing, dropping the volume level of either a bit. When in the off position the volume is raised back to “normal” or what is considered Turbo mode here. While not quite as brutal as the Turbo mode on iDSD Diablo or the older micro–Black Label, it does raise the volume enough to warrant me turning the volume down first.

The bottom carries the lined 3.5mm se and 4.4mm bal jacks while the top houses the USB-C connection port. Simple and straightforward to operate, it does carry extra weight compared to its competitors.

Wired Connectivity:

USB-C to USB-C

Using the included cable for connection to my MBP was seamless and permission was immediately asked to allow connection. Entering Tidal, the Kensei was already connected (which does not happen on some items I have reviewed of late).

The connection was stable, and the Kensei could easily lay on the desk next to the MBP with just the right length of the cable.

USB-C to Lightning

The same can be said about connecting to my iPhone, but the heft of the Kensei was felt more here. Permission was granted again and I was listening within a few seconds to Tidal and Qobuz.

Battery impact:

I was seeing 5-7% per hour on my MBP, and that much or more on my iPhone. Not the best, and not the worst I have encountered.

Sound Impressions:

All sound impressions were made on my iPhone 13 Pro Max, MBP, or HiBy R4 using a combination of the Spirit Torino Twin Pulse IEM, Campfire Audio Solaris 2020, or the Meze 99Classics.

Summary:

iFi products to me have always slanted a bit (or more) towards a warm, musical signature, with richness and an organic nature to them, which separates them from competitors. The Kensei, while sharing some of those characteristics comes across as musical but with a lighter hand in the overall sound signature. Brighter, compared to my desktop Pro duo, the Kensei immediately sounds more succinct in sound quality, with an accuracy that sets itself apart.

Both ends are lifted a bit, making for the typical V-shaped signature, but mids still come across as harmonious, melodic, and detailed; if a bit lifted and behind the extremes.

K2HD effect:

The K2 implementation makes the end product sound more natural to me, giving the overall sound signature a bit more clarity and detail. There is a slight amount of holography as well, with a more musical note to it.

The bass response becomes a bit more pronounced, with an increase in presence (especially with XBass+ on). The mids come forward while the treble gains some presence. Both seem to be “closer to true” than before.

The overall stage is more energized and the timbre becomes organic. Layering seems to take on levels not heard before, which becomes closer to the original. I found Pop and Rock work well here, but jazz also becomes more sensual in tonality.

I am a fan of vinyl and the Kensei embraces that vintage sound, albeit with excellent translation moving away from the “typical” analog sound often heard with devices that promote detail and clarity first and foremost.

Timbre:

There is what I call a “typical” iFi sound, which comes across as vibrant, detailed, and rich. But one not having the most clarity. There is a definite sound to it, which purists may not like; but as mentioned above the K2HD implementation goes a long way towards combining all of this into a coherent sound.

The Kensei lies on the warmer, richer side of life; with thicker notes giving a velvety touch to the music, but with sufficient clarity to satisfy most. While detail retrieval does suffer a bit as a result of this, the K2HD implementation and XSpace go a long way toward combining the best of both worlds. I am beginning to see the value of such a device, especially for those who may want something that works across many platforms and in many situations.

Think of the Go bar Kensei as a device pining to be a desktop unit besides a portable device.

Even without XBass+ and XSpace toggled on, the sound carries a good holographic feel to it, along with detail in its character. There is a solid if not depth-reaching bass line holding the foundation, with the mids coming forward. Treble reach carries good height without becoming grating or too much sizzle for my liking.

Add in XBass+ and XSpace though, and the sound be very immersive. This to me makes for the more typical iFi signature sound. Raising the volume becomes a necessity as you engross yourself in the music at hand.

Staging & Dynamics:

The soundstage without XSpace on is good, equally spread in all three dimensions to me. Adding XSpace to the equation makes for an out-of-head experience in all three dimensions. This adds to the holographic sound to me, allowing the layers to become more prevalent and discernible. Not in a separate way, but cohesive. Expressive notes come across with excellent heft and the right amount of thickness. All while not becoming thick or slow in response.

Transient response especially with XSpace takes on those extra detailed levels in a good way without becoming too expressive or sharp in shortness. I have always what appreciated XBass+ and XSpace can do, and this is no different. Some might think this added filtering makes for a less-than-realistic sound, but I would rather have the choice(s) of this than not. There are times when I leave both on and others where both are off or use one singularly. To me, that is the benefit of having that choice. Change when you feel like it.

Dynamically speaking this can compete with some of the best out there, including the Questyle M15, while also having the ability to change some “filters” to your choice.

Pairings:

For ease of use, while typing this out, I connected the iFi GO bar Kensei to my MBP, which of course limited its CODEC response. That said, Tidal still sounded full and vibrant with a rich character that made me appreciate the positive response hooked together. Playing with XSpace and XBass+ allowed me to tailor the sound to my liking, even with those limitations.

Switching to my iPhone 13 Pro Max with similar limitations still afforded me better sound than without, by a good amount. Transient response was faster, with better clarity coming forth, without losing the depth of the notes. iFi’s traditional note-weight heft shone through without becoming drippy. XSpace and XBass+ were a wonderful treat, but not needed as much with this pairing. I still used both regularly, especially when the song needed more volume to satiate my appetite.

Moving to a non-iOS device in the HiBy R4 allowed me to experience more options to stretch the legs and strengths of the Kensei. All music had to be played through the USB Audio Pro app, but logging into Tidal and Qobuz was easy and play within the app was seamless across SD card and the streaming platforms.

The R4 carries a bit of richness to its signature, but with a bit of flair to it, which I appreciate. Adding the Kensei into the equation raised that flair factor, adding depth to the low end as well. Mids were moved forward a bit using the Kensei, too. Playing Los Lonely Boys came across as raucous & fun, with a rich, warmer signature giving me an immersive effect.

IEMs/Headphones in use:

I leaned heavily on the Meze 99Classics with the DDHiFi BC150B 4.4mm bal cable and came away impressed. The only “fault” I can find with the OG 99’s is a tendency to sound a bit thin in sound signature. I still consider it one of the best bargains out there, especially used (my pair was used and it was in “as new” condition). A simple aftermarket cable and the addition of the Kensei have made me appreciate the versatility of the 99’s even more now. The Kensei took the 99’s positives and added an extra bit to each segment, which was greatly appreciated and could be “tuned” by turning both XBass+ or XSpace on or off.

When I reviewed the Spirit Torino Twin Pulse IEM, I came away impressed with the sound, while thinking I would like to try their headphones in the future. Until then, this will certainly do. Adding the Kensei to it, the vibrant tonality stuck out to me yet again. The Kensei comes across as typically iFi in its warmer signature, but the clarity coming forth adds to the Kensei’s reputation for quality along with the “house sound.” Using this pairing I gauged the sound equally impressive and palatable with and without XBass+ or XSpace turned on. While I did prefer both to be activated in this setup, the punctuating mids coming out filled in what I might consider the Spirit’s weaker point. The midrange is very, very good, but a bit behind the signature. Using the Kensei brought the whole into focus again, heightening my overall appreciation of both.

The CFA Solaris 2020 is a polarizing unit. When I reviewed Thomas’ copy, I came away with the positives of it being my favorite of the 2020 trio release. Tight control of the bass coupled with mids that define the CFA legacy were accentuated using the Kensei. Bass reached a bit deeper using XBass+, and the spatial awareness of the sound became a bit tighter and more detailed using XSpace. The DDHiFi Nyx Pro is an astounding cable for the price but does bring with it a punctuating midrange that may not be the best choice for the Solaris 2020. But I used it anyway, and combined with the Kensei it made for a thoroughly engaging signature, especially with electronic-oriented music such as Jamiroquai’s Deeper Underground. Punctuating treble notes and a solid bass foundation made me think I was in a fine Paris underground nightclub. A good mix again.

Select Comparisons:

You should ideally have 3 comparisons but 2 is ok also if you are short of options. If you only have one then talk to me as we can tailor something different.

Choice of comparisons should be a factor of similar price, similar features and ideally, brands people identify with but I know that is not always possible. Talk to me about this if you have concerns.

Cayin RU6

Technical

At $249, the RU6 is half the price of the Kensei, and much simpler. The RU6 is a 24-bit R-2R DAC, which comes with 48 resistors (23-R & 25-2R) per channel, totaling 96 resistors. As opposed to the typical Delta Sigma DAC, the R-2R is a ladder-back array as mentioned above. This can purportedly isolate potential feedback better making for a “purer” sound coming forth.

With power up to 138mW at 32ohms in 3.5 and 213mW at 32ohms in 4.4, that may not seem like much. Coupled with the device LO set at 100 typically, I found the power much more than adequate. The large SNR ratios of 113dB’s and 114dB’s (20Hz-20kHz, A-weighted) respectively played into the versatility of the RU6, too.

Design

At 65mm x 25.4mm x 13.7mm and 28g, the RU6 is slightly larger, but half the weight of the Kensei.

The black glossy plastic does make for a fingerprint magnet, but the orange case not only looks fabulous it gives you better tactility. Plus, with only three buttons to control, usage becomes second nature. The difference here from “typical” dongle/DACs is that the volume buttons are next to each other instead of sandwiching another control.

That last button (closest to the headphone jacks) controls access to the simple menu, which contains gain (H/L), sampling (NOS/OS), and the backlight. Accessing this functionality requires a long press, which keeps it from accidentally being pushed. This is especially good since gain is the first option.

Performance

While comparing some dongle/DACs in this price range, the RU6 quickly became my favorite along with the Questyle M12…until I heard the RU7. Separating that, the RU6 is vibrant and tantalizing in signature with a sound that may be too bright for some.

Digging deeper reveals that the forward nature of that sound is excellent detail retrieval and an increased level of clarity. Cayin knows a thing or two about producing portable devices, and the RU6 is a home run in the semi-affordable market.

The differences here are usable features and the definitive difference in sound signature. If you prefer a tighter, more accurate signature, the RU6 wins. But if you want a more immersive sound, one which can draw you in allowing some level of control; the Kensei wins to me going away. Both are excellent in their own right, though.

Cayin RU7

Technical

Currently on sale for roughly $220usd, the RU7 would be considered a steal for that price. With a 1-bit resistive ladder DAC configuration, Cayin continued its adaptability in forging a different path. Sharing some technology with an in-house item, as does the Questyle mentioned below. Nominally more powerful than the RU6, the output of 160mW on a 32Ω load, and balanced output of 400mW make for a very adequate jump across your devices.

Both the R-2R for the RU6 and the 1-bit for the RU7 were the first of any kind in the dongle/DAC world. There is a degree of similarity to how R-2R and the 1-bit work using matching 0.1% resistor ladder arrays for conversion. The 1-BIT DAC however benefits primarily apply to processing native 1-BIT DSD, as opposed to PCM, which is multibit. Arrayed in 128 pieces (4×32) the resistors go through a 3-level LPF conversion before being converted to a single-ended signal for volume adjustment. This is almost unheard of adding dynamic range and channel consistency not often heard at this level.

The RU7 with no FPGA differentiates between the two signals (PCM & DSD), adopting an “all-to-DSD” processing approach. That means both PCM and DSD get processed (upsampled) to DSD before being sent to the DAC, an approach that yields benefits in sound impressions well beyond what it should.

The RU7 decodes up to DSD256 natively as well as PCM up to 32BIT/384kHz, consistent with the RU6’s decoding capability.

Design

At 66m x 24mm x 12mm and 25g, it is lighter than the RU6, but roughly larger than the Kensei. The black glossy shape again carries fingerprints. I am again thankful for the good-looking green case, which adds looks and tactility to it.

The LCD screen also carries more sub-menus including “All to DSD,” which is the LPF mentioned above as well as output (PO/LO), gain (L/H), and backlight (complete with changeable timer).

Performance

I like the RU6 performance. I love the RU7 performance. Rich, and velvety but with finesse and substantive increases in clarity make this one of the best dongle/DACs out. Yes, there are newer ones, but the level of detail wrought from the 1-bit ladder array makes me a believer.

While not quite having the bass depth of either the RU6 or Kensei, the quality of sound makes up for that “lack” of reach down low. Mind you it is still there in plenty, but without the sub bass reach of the others.

Changing the DSD filter can alter the signature a bit when utilizing something that handles DSD, but is pretty useless on iOS devices. Nonetheless, the majority of the planet can enjoy the decoding levels.

If I had to choose between one, it would come down to features vs sound. There is no denying the absolute gem the RU7 is in terms of sound. Considered by many as one of the absolute best dongle/DACs out, I cannot deny that. The Kensei has filter-changing abilities, and slightly more power, which can sway some, but this will come down to whether you prefer pure unadulterated sound versus the ability to add spatial awareness and extra bass down low. I cannot decide.

Questyle M15

Image courtesy of Headfonics.com

Technical

At $250, the M15 comes in at half the price of the Kensei as well. Carrying the company-patented CMA (Current Mode Amplification) like its desktop units in 2 SiP modules, the familial sound here is as telling as iFi’s. Using the ES9281AC PRO chipset, the M15 goes for a different approach than many of today’s Cirrus Logic choices (but the same choice as the M12).

A 32-bit two-channel DAC make for use up to DSD256 native and PCM 32BIT/384kHz as well as an 8X MQA hardware unfolding capability. The Torex power management unit along with 11.97mW @ 300Ω (3.5mm se), and 22.60mW @ 300Ω (4.4mm bal), seem extraordinarily low, until you see that is at 300 Ω. The M15 provides plenty of power for most devices.

Design

At 61.8mm x 27.2mm x 12mm and 28.5g, it is bigger and heavier than the other two comparative efforts here. With an open side, you can see the insides at work, complete with a light denoting CODEC, but does fall behind the others at DSD128 only. I like the look of it and preferred it to the others due to the ability to see inside.

Performance

The Sabre-equipped chip M15 pretty much set the bar for sound when it came out. The then lofty price of $270 was “justified” due to its extraordinary sound emanating from within. I found myself not wanting to give back the loaner unit at the time, contemplating the selling of much of what was sitting on my desk as “desktop units.”

The levels of detail wrought from the M15 far surpassed pretty much any dongle out, and I still lament for a Questyle desktop unit such as the CMA15 or even the CMA12, they sound so good. For those looking at purely sound, this is the benchmark to me (RU7 is a close second). Levels of detail you thought were not possible from a dongle/DAC come forth with waves of euphonic clarity. Exacting sound is one thing, but to do so with emotive effects as well comes down to the tuning of that ESS Sabre chip and Questyle’s in-house engineers; which need to be given a hefty raise.

But a large downside does exist: when using an iPhone, you need the Apple camera adaptor to get proper power to the unit. The iPhone power sent to the M15 is insufficient to properly drive it or drive it at all according to multiple reviews (my results as well). Once this issue was taken care of, the functionality was fine. But to those of us using an iPhone, the levels of gain from a dongle pale in comparison to Android or Linux users. If this was on pure sound, the M15 would be my choice, but factor in the functionality issues (there is now an M15i that has corrected said issues) and lack of customizing and the Kensei makes a strong case for itself.

finale:

The iFi GO bar Kensei is the latest iteration of the venerable GO bar series. The OG GO bar cost a pretty penny itself, setting the bar (so to speak) high, while winning awards as the top dongle out. The Kensei, with its additional K2HD sound enhancements and new shell, raises that bar even higher.

Providing excellent sound to start with, the user can add bass or soundstage via a somewhat holographic effect tailoring the sound even further. To do this, the price has been raised. We are now entering into the category of solid-performing desktop DAC/amp units that have more connecting options and most likely provide more power. So where does the Kensei fit in?

The Kensei will provide the user with an excellent option to add more power to their Smartphone (which many now arguably do not need) or laptop, while also enhancing the sound coming forth. This is probably its greatest strength twice over: more power and enhanced sound. Who doesn’t want that for when you need to drive your hard-to-drive headphones through your laptop or Smartphone?

The downsides? The price for one, and the fingerprint-prone stainless-steel shell. Another downside to me is the small lettering on the Kensei which is also harder to see on that shiny surface. And (minor) like any portable iFi device, both sides are worth looking at, but one will be face down most of the time covering most likely the Japanese script.

But the positives, including the excellent IEMatch, more than make up for the cost increase. Especially when we consider the sound coming forth from the Kensei. For those looking at a portable solution that while heavy, provides excellent sound characteristics, plus the venerable XBass+ & XSpace; the Kensei is well worth a look and muscles its way to the top (or close to) of the dongle/DAC category.

I again thank Lawrance and iFi for the loan of the Kensei and appreciate their continued support. The Kensei will be missed, so I guess my desktop units will have to do it for now.

Cheers.