Intro.
It has been over three years since the original Cayin N8 release back in October of 2018, the first portable audio player with Solid State and Korg NuTube (6P1) dual output design. For those who are not familiar, NuTube is a double triode tube which implements vacuum fluorescent display technology in a compact low power design that operates similar to traditional triode vacuum tubes. N8 had a lot of other cool features, but the dual output including NuTube was definitely the highlight of the design, even though some audiophiles questioned why it was only available from 3.5mm output without realizing that if you want to have a truly balanced architecture, you need to have 2x 6P1 modules, similar to Cayin’s C9 portable amplifier.
The non-Android nature of N8 played a big role in the longevity of that release, but sooner or later you have to move on to the next gen which Cayin has been working on for a while now. According to Andy Kong, Cayin even had to restart the design due to DAC availability issues after AKM factory fire, forcing them to search for a new flagship DAC. Plus, when N8ii model name was announced, some missed the significance of “ii” suffix, assuming it stands for “mk2”. It certainly does, but there is also another clue associated with it. Cayin always uses “i” with their Android DAPs, and N8ii model name was a dead giveaway of next gen N8 joining the list of their previously released Android-based i5, N5ii and N6ii audio players.
I started working on my First Look write up prior to the availability of N8ii spec and design details and had a very short time with this DAP before it went back to Musicteck in preparation for CanJam NYC show where it made its debut. Thus, my initial First Look review didn’t have the complete design description and was missing my usual Comparison, Pair-up, and Wired/wireless details. After the show, I received the official review unit and spent a month with this new flagship DAP from Cayin. Here is my Full Review of N8ii, and I hope any open questions from the First Look have been answered in this updated write up.
Unboxing and Accessories.
The unboxing experience of N8ii is very similar to their C9 amplifier and Fantasy IEMs. The removable outer sleeve in the final packaging doesn’t have the same cutout around “8” like it had in pre-production packaging, but the rest is all the same, including a glossy DAP picture on the box cover underneath. That giftbox quality packaging box had a split magnetic top cover to reveal a non-removable foam insert with a secure cutout for N8ii and another magnetic side door for a sliding tray with accessories. In a gap between these magnetic covers, there is a metal tab with N8ii model number. Besides having a premium presentation, I also found it to be very convenient to access the accessories without digging through or removing layers inside of the storage box.
Included was a premium quality usb-c to usb-A charging/data cable, L-shaped 2.5mm to 4.4mm and 2.5mm to 3.5mm adapters, and tempered glass screen protector. A film screen protector was already applied to the back. While my First Look review mentioned a
brown prototype case, the final version of N8ii arrived with a teal/bluish color leather case. According to Cayin, it uses a premium Italian leather, and utilizes a metal grille on the back for enhanced heat dissipation and airflow. This particular case has a fully open top where N8ii slides in, open bottom to give access to all the ports, split window on the left side for NuTubes, and covered hw playback buttons and micro-SD slot on the right side.
The case I received fits N8ii like a glove, tightly and securely wrapping around the DAP. I have read comments on head-fi with some people finding the case to be a bit loose. Not sure if some of the units from the first production batch had a looser fit, but I can only speak for the one I received which I found to be just perfect.
Also, some might remember that original N8 had 4.4mm to dual XLR adapter cable, but it is not included with N8ii anymore. Back when N8 was released in 2018, such breakout cable was rare, and Cayin decided to make a custom one. Today, there are many cable adapters in different price brackets, and Cayin decided it is unnecessary to include it with N8ii.
Design.
This section carriers over from my First Look
review. I found it doesn’t require any additional info.
N8ii vs N8
Relative to the original N8, the exterior of N8ii has been completely redesigned. With dimensions of 147mm x 77.5mm x 25mm and the weight of around 442g, this DAP is on a bigger and thicker side, but I still find it to be portable rather than transportable. It is definitely thicker than your average flagship DAP, and one of the reasons for that was upright position of two NuTube modules. Everybody wants to see a pair of NuTube green “eyes”, and to accommodate that, Cayin has both modules upright, on the left side, facing outside through the glass “window”.
The sculptured design of N8ii aluminum chassis is not your typical rectangular brick. The front is occupied by 5” OLED display with 1280x720 resolution, surprisingly lower than some of the other flagship DAPs with large display, though not an issue to display album artwork in vibrant colors. Below the display you also have multi-function soft touch home/back button for navigation. The left side has two angled facets with flat glass windows in the middle to showcase the glow of NuTube modules. Right side closer to the bottom has spring-loaded microSD card slot for storage expansion, and 4 round buttons at the top – a larger power button and 3 smaller playback (play/pause/skip) buttons below it.
The top has an interesting, angled-facet design as well, including a cutout in the top right corner for a “golden” volume wheel with an etched artwork that reminded me a bit of LPGT. The volume wheel is open at the top and has easy access from the front and the back. At the bottom, you have a shared 4.4mm PO and LO outputs and dedicated 3.5mm PO and 3.5mm LO ports. To the right in the corner, you have usb-c port for charging, data, usb audio in, embedded SPDIF, and digital-out functionality, and I2S port for connection to other desktop equipment with the same port connector. The back of N8ii looks like it has a glass panel.
Under the hood.
The new Cayin N8ii is packed with a lot of top-grade goodies under the hood. From what I heard, the original idea was to have dual AK4499 DACs, but after AKM fire the plans have changed and Cayin decided to explore other DACs outside of AKM, ESS, and CS. N8ii features a high-end ROHM BD34301 32bit/768kHz (DSD512 supported as well, and MQA certification is coming soon) current mode DAC chipset from their MUS-IC series, being the first portable DAP to introduce it. Another addition to the design was using dual NuTube 6P1 (double triode tube) module, instead of a single one like in N8. You still can select between Solid State and dual NuTube timbre, and now can also enjoy both in a fully-balanced configuration. And similar to original N8, you also have either standard P or high output power P+ mode which boost the operation voltage of internal headphone amp to increase the output power. The new addition to the design is its fully discrete headphone amp being balanced now and having Class A and AB amplifier modes like in C9.
Cayin already had a lot of experience with NuTube implementation in their N8 and C9 products. Similar to those designs, N8ii uses flexible printed circuit (FPC) and custom-built shock-absorption silicon housing to hold, to damp, and to minimize shock transmission, and to eliminate microphonics as you move around with N8ii. And to isolate and to prevent interference, they designed compartmentalized CNC aluminum chassis with a vertical-hanged suspension pin to mount the NuTube and its silicone housing securely.
The dual output mode, P and P+, actually regulates operational voltage of amplification circuit where P+ will boost it up which has a noticeable effect on sound signature. It’s not the same as gain control, you still get L, M, H gain, but with P+ the output voltage scales up higher. And the dual amplifier operation mode gives you a choice to switch between Class A and Class AB modes of discrete amplification circuit, adjusting the bias point which also results in a noticeable sound change of the output.
Furthermore, N8ii is no longer playback only DAP like the original Unix-based N8. Now, N8ii is running a highly optimized Android 9 OS and using Snapdragon 660 SoC along with 6GB of LPDDR4X RAM and 128GB eMMC internal solid storage. If you want to expand the storage, you can use microSD card. The open Android OS, courtesy of Hiby, uses DTA architecture which bypasses Android SRC to make sure audio, regardless of local or streaming playback, is not down-sampled. The 3D Benchmark performance of Android 9 OS in N8ii has the highest score (191572) I have seen in comparison to other Android DAPs on the market. I’m using AnTuTu v8.4.3 test app, while revised AnTuTu v9.x recalculates this score to be over 200000. But it is not just a benchmark score, in practice the DAP feels very fast and responsive.
The battery has high capacity, 10,000 mAh (3.8V), assuming the same battery as Hiby R8, which I also suspect as being baseline Android platform for N8ii design. In my battery test, while being in P mode, Tube output, Class AB amplifier, medium gain, and using BAL output, I was able to get a little over
9hrs of playback time. Switching from Tubes to Solid State can give you even more playback time, to reach closer to 10hrs. And thanks to support of QC3.0 (and PD2/3), you can charge N8ii faster. Just please be aware, when you are playing and charging at the same time, especially in more demanding Class A (less efficient) mode with Tubes (higher current) selected and leather case on (less air cooling), N8ii will get warm and can trigger overprotection shutdown if internal temperature crosses 50degC threshold.
Implemented was also Bluetooth 5.0 with a support of all common wireless protocols up to LDAC, and dual WiFi with 2.4G and 5G bands. The output spec is impressive as well, where
4.4mm BAL output (1.2ohm output impedance) gives you
750mW @32ohm in P+ high output mode, and
3.5mm SE output (0.6ohm output impedance) gives you
480mW @32ohm in P+ high output mode. But it’s not always about power numbers. For example, switching to P+ can give you a more noticeable sound improvement than using another DAP with a higher output power.
During my testing I made a few interesting observations. First of all, you do have Double-tap option to wake the screen, very convenient feature that works quite well in N8ii. Also, whenever you switch modes or go between SS/Tubes or amplifier types, there is a gradual volume increase instead of a quick change to make sure you don’t blast your ears. And one thing that was very important to me, thanks to compartmentalization and isolation of NuTubes from WiFi antenna, when I’m streaming with Tubes output selected, I never experienced any EMI interference.
Sound Analysis – Overall.
The sound analysis of N8ii was done using Oriolus Traillii, playing a selection of test tracks, such as Agnes Obel “The curse”, Sandro Cavazza “So much better” (Avicii remix), C-Bool “Never go away”, Ed Sheeran “Shape of you”, Alan Walker “Darkside”, Galantis “Hunter”, Iggy Azalea “Black widow”, Indila “Boite en argent”, Dua Lipa “Love again”, Counting Crows “Big yellow taxi”, David Elias “Vision of her”, and Michael Jackson “Dirty Diana”. I had about 150hrs of burn in time before I started analyzing N8ii.
I prefer to describe the DAP sound based on the comparison to other DAPs and pair ups with different IEMs/headphones since the DAP by itself doesn’t have a “sound”. What we hear is how the sound characteristic of a source shapes the sound signature of connected IEMs/headphones or the difference in sound relative to other sources using the same pair of IEMs/headphones. As a result, this section of the review usually summarizes what I find in the follow up Comparison and Pair-up sections. Of course, this is my subjective opinion, describing how
I hear it.
I found the tuning of N8ii to be more transparent and to have a natural revealing tonality. The difference in timbre setting between Solid State and NuTubes will have the effect on mids and vocals from more revealing and dryer (SS) to smoother and more natural (Tubes). But overall, it has neutral sound with a balanced signature leaning toward natural
revealing tonality with expanded vertical dynamics (both micro and macro), black background (very quiet noise floor), and relatively fast and clean transient response of notes with details popping out of the blackness, even when it comes to sensitive iems.
The Tube mode gives instruments and vocals more body, more texture, richer timbre, while still keeping the sound quite resolving, layered, and with impressive retrieval of details. Those who are familiar with the original N8 or C9 amp, know that NuTube is not your traditional “tube” that colors the sound. NuTube’s double triode tubes are rich in texture, not coloring or saturation. But still, when you switch from Tube to Solid State, you can sense more transparency and less coloring in sound.
Soundstage is
big, especially from balanced output, expanding in all 3 directions, making the sound very spacious and open. Also, impressive 3D holographic imaging with a very precise and accurate placement of instruments and vocals in most of my IEMs and headphones.
4.4mm vs 3.5mm.
The only noticeable difference I hear is in soundstage width, spreading wider (Left/Right) when connected to balanced output. Also, BAL has more power, thus SE needs a few more volume clicks to match it. Otherwise, tonality, sound sig, and overall technical performance were nearly the same.
Hissing test.
N8ii is relatively quiet with Solaris 2020, passing my Agness Obel "The Curse" first 30sec test without a problem. I tried it with P/P+, SS and Tubes, and Class A/AB (in P mode). There was just a slight background waterfall hissing in high gain, but nothing in middle or low gain.
EMI/RFI interference.
Tried a few extended listening sessions streaming Amazon Music HD and Tidal, and even with my S22 phone next to N8ii I haven't noticed any EMI interference.
Sound Analysis – SS/Tube, Class A/AB, P-mode.
Please keep in mind that in P-mode (regular output), you have a choice of either SS or Tubes output and can switch between Class A or Class AB amplifier type. In P+ mode (higher voltage output), you also have a choice between SS or Tubes, but can only select Class AB amplifier. So, between P and P+, Solid Sate and Tubes, Class A and Class AB, not to mention 3 levels of gain on top of that, you have a lot of different combinations to try with your IEMs and headphones. To give you a better idea what you can expect, I partitioned my testing as following. Also, please keep in mind, while I find changes noticeable, nothing is night-and-day drastic.
The P mode
Class A to
AB comparison applies to both
SS and
Tubes timbre settings. Switching between Class A and AB is like going from a smoother and slightly more laidback and relaxed analog sound to a faster, snappier, and with a blacker background Analog/Digital hybrid sound. The difference in tonality is noticeable due to speed/attack change in the sound where in
Class A - bass has a slower attack with less punch, mids are smoother, more relaxed, with a little more analog warmth, treble has a bit less sparkle, and in
Class AB - bass has a faster attack with more punch and improved articulation, mids are more resolving, and have blacker background, treble has more sparkle and airiness.
In P mode
Class AB, when switching from
SS to
Tubes, there is a clear distinction of the sound gaining more body and smoother analog texture in mids/vocals. As a result, in
SS timbre setting the sound is dryer, has more precision and control, and faster transient of notes popping out of the black background. Switching to
Tubes makes mids/vocals wetter, smoother, even a touch warmer while still keeping the same high resolution and retrieval of details. The technical performance doesn't change as much, but the coloring of the mids becomes more apparent.
In P+ mode
Class AB when switching from
SS to
Tubes, I hear the same changes as I noted above in my comparison while testing in P mode.
After a number of extended listening sessions, I found that in P mode with SS timbre I preferred Class A setting which gave me a perfect combination of faster sound with higher resolution and smoother analog coloring. But, when I was in P mode with Tube timbre, I enjoyed more Class AB amplifier setting to give the sound more punch, to improve the layering, and to add more sparkle to the upper frequencies.
In P+ mode, since Class AB was the only amplifier option, choosing SS or Tubes will depend on pair up synergy with IEMs I was using. For me personally, warmer smoother IEMs paired up better with SS while brighter or neutral tuned IEMs had a better synergy with Tubes.
Also, switching between P and P+ to boost the output voltage/power, had a different effect depending on your IEMs or headphones. For example, when listening to BA/EST iems (like Traillii), it didn't make as much difference to my ears. But when I switched to hybrids with
DD/BA/EST drivers (like Jewel), the bass punch had more authority, better articulation, and a tighter sound. This effect was even more noticeable when I used demanding headphones like my 470ohm open back ATH-R70x. The boost in performance of R70x when I switched to P+ was quite impressive, including a better articulation of bass notes, more clarity and blacker background in mids, and some expansion in soundstage. Also, I noticed same changes with Meze Audio Empyrean.
Overall, P+ with Tubes and Class AB was my favorite setting with most of my IEMs and headphones, but I also enjoyed Solid State with P+/AB. I think the choice will be based not just on pair up synergy, but also the preference of tonality. Either one offers a unique finetuning of the sound and makes you feel like a mad audio-scientist, experimenting with different settings.
Comparison (Line Out test).
In this comparison section I’m going to cover 2 specific test scenarios. In each one I was using Traillii w/First Times cable, volume matched.
Test 1:
N8ii PO (P+ mode, Tubes, Class AB, 4.4mm BAL)
vs N8ii LO (4.4mm) +
Cayin C9 (Tubes, Class AB, 4.4mm BAL)
This was a very interesting and important comparison because I'm sure many will have a question if N8ii internal dual NuTube amp is similar to C9. In this particular testing with Traillii, I'm only switching between internal N8ii dual NuTubes and external C9 dual NuTubes. To my surprise they don't sound exactly the same. N8ii PO has more weight in bass, especially sub-bass, and smoother upper mids. In comparison, N8ii LO w/C9 has a bit less sub-bass rumble and slightly more forward and brighter mids. And not only with IEMs, but also with headphones, I found the change to be consistent. Also, the soundstage expansion and imaging were nearly the same in this comparison.
Test 2:
N8ii PO (P+ mode, Solid State, Class AB, 4.4mm BAL)
vs N8ii LO (4.4mm) +
Romi Audio BX2 (Solid State, 4.4mm)
BX2 is a very transparent solid state Class A amplifier which I often use to evaluate the DAC “sound” from LO of the DAP. The reason I was curious about this comparison is because I already know the effect of NuTubes inside of N8ii relative to switching from Solid State. But I also wanted to find out the effect of SS inside of N8ii on top of its ROHM DACs. What I found is that N8ii internal SS amplifier is quite transparent as well. Maybe just a touch smoother in upper mids when compared to LO+BX2, but it wasn't too far off. It also made me realize that ROHM BD34301 DAC is not too far off in comparison to AK4499, though probably being even more transparent and resolving.
Comparison (vs other DAPs).
This section was missing in my First Look analysis, and of course I got hundreds of questions with suggestions what I should compare. I was using Traillii and Jewel in this testing, volume matched in every comparison. Also, please keep in mind, I’m only focusing on sound comparison. Each DAP has its unique functionality. Some are Android based and can load any streaming app. Others are audio playback only and can be connected to your smartphone wired/wireless to be used as DAC/amp for streaming.
N8ii (P+/Tube/AB, 4.4mm) vs Cayin N8 (P+/Tube, 3.5mm) - N8ii soundstage expansion is wider in comparison to N8. N8 soundstage is spread L/R wide, but N8ii wraps the sound around you, putting you right in the middle of that holographic expansion. N8ii background is also blacker which gives its sound more speed and precision, but at the same time takes away a bit of that warmth and that mildly veil background blanket that gives N8 a more analog tonality. Switching N8ii to P/Class A gives the sound more smoothness, bringing it closer to N8. In general, I don't find the difference between these DAPs to be night and day. Yes, you can hear N8 being a bit smoother and warmer in mids while N8ii has more precision, more speed, and more of natural transparency. The sound of N8ii is still less digital and more analog, but it has a bit less coloring in comparison to N8.
N8ii (P+/Tube/SS/AB) vs Shanling M9 - With N8ii in SS output, the sound performance of M9 and N8ii is very similar, from technical performance of the soundstage expansion to layering and separation of the sounds. But with SS output, N8ii tonality is a just a little bit more revealing in comparison to a bit more warmth in M9, especially mids/vocals. But once you switch N8ii to Tubes, and then play around with Class A vs AB, the N8ii now sounds smoother and with a bit fuller body in mids when compared to M9. Based on this, M9 tonality is somewhere between SS and Tubes of N8ii.
N8ii (P+/SS/Tubes) vs Sony WM1Z - N8ii soundstage is a bit wider; the bass impact is very similar, though I hear WM1Z to have a little more emphasis on mid-bass while N8ii has a bit more emphasis on sub-bass. The difference in tonality I'm hearing is WM1Z being a little brighter in upper mids and treble, while N8ii (both ss/tubes) is a little smoother and more organic in upper frequencies in comparison to WM1Z. And this holds true even when enabling Vinyl Processor effect on WM1Z. But what I find interesting, while N8ii sounds a bit smoother, it has a higher perception of resolution in comparison to WM1Z which has brighter upper frequencies. You also do have to keep in mind, WM1Z is underpowered.
N8ii (P+/Tube/AB) vs Cayin N6ii w/E02 (LO) + C9 (Tube/AB) - This was probably one of the most popular comparisons requests I have received, or I should say, the 2nd most popular because I don't have A02 LO card. First of all, soundstage is a perfect match here, both being wide and holographic. When it comes to sound, there is a noticeable difference in this comparison. With my pair of Traillii, the bass with N8ii has more punch and deeper sub-bass rumble, scaling up with more weight in comparison to slightly more polite bass with E02/C9. Mids tonality is different as well, with N8ii having more body, a little more coloring, and overall warmer timbre. In comparison, E02/C9 has more transparency and a little less coloring, less warmth for sure. And the same with treble, E02/C9 has more sparkle while N8ii treble is smoother, still well defined and with a nice crunch, but relative to E02/C9, N8ii treble is smoother and more laid back.
N8ii (P+/Tube/AB) vs Cayin N6ii w/T01 (LO) + BX2 – Another request someone posted, asking for comparison. N8ii soundstage expands wider. Both have a warmer tonality, but besides the "warmth", N8ii has a smoother and more layered sound, while T01+BX2 makes the sound a bit raw, more forward/aggressive, and a bit compressed to my ears. I'm using the original BX2 which is very transparent and has too much gain.
N8ii (P+/SS/AB) vs A&K SP2000 - I went back and forth dozens of times and also compared it in a blind test. With the exception of N8ii having a bit wider soundstage and a little more rumble in sub-bass, these are nearly identical in sound when N8ii is in Solid State. When switching N8ii to Tubes, I hear more weight in N8ii bass and mids gaining more body and tonality being warmer. In solid state the difference is quite subtle.
N8ii (P+/Tube/AB) vs L&P P6 Pro - This comparison was another surprise, and it took me over a dozen of times going back and forth, comparing these two. The soundstage is nearly identical, maybe with N8ii being a touch wider, but it is hard to notice. The tonality is very close when N8ii is switched to Tubes mode; perhaps P6 Pro is just a little bit warmer in mids, but that's about it. Overall, nearly the same technical performance with a dynamic layered sound that comes very close when comparing these two DAPs.
N8ii (P+/SS/AB) vs Lotoo LPGT - This comparison is not too far off either. I do hear soundstage being a little wider with N8ii. Also, N8ii, especially in P+ mode, has stronger bass punch. But when it comes to tonality and technical performance, LPGT and N8ii Solid State are very close. When Tubes are selected, the performance gap widens since N8ii gains more textured sub-bass rumble and more body/warmth in mids. But in Solid State, it's a closer match.
N8ii (P+/SS/AB) vs iBasso DX300 MAX SS - Both have a very wide holographic soundstage, finally a perfect match! They also have a similar technical performance with an excellent layering and separation of instruments and vocals. But tonality is a bit different. Starting with a bass while using Traillii, I hear more sub-bass with N8ii and stronger mid-bass punch with 3Max. 3Max mids are brighter, while N8ii has fuller body with a more natural and still revealing tonality. And the same with treble, 3Max has a little more sparkle while N8ii has a more natural definition of the treble.
Pair up.
In this section of my review, I will go over how various earphones and headphones pair up and how they sound with N8ii. I used P+ and Class AB and Middle Gain in each pair up, and will note Volume level (V#), and compare SS vs Tube. These are brief notes to give you a basic idea.
Pair up with Headphones.
Audio-Technica ATH-R70x (V66) – This pair is a perfect example of demonstrating the power of P+ boost when dealing with demanding headphones such as these
470ohm open back cans. Regardless of setting, the soundstage expansion is super wide open and 3D holographic even though I only have and use 3.5mm SE cable with these. Sound signature is very balanced, and tonality is natural and revealing. Not bright or brittle, but revealing, natural, and micro-detailed, something I don’t usually say when describing R70x; don’t think I ever used “micro-detailed” in any other R70x pair up descriptions. The bass performance is excellent, with a deep sub-bass rumble and a slightly laidback mid-bass punch. The weight of the bass in this pair up is in sub-bass, and a bit slower attack of mid-bass make the bass more natural and fuller. Mids have a natural body, clear, detailed, layered, with a perfect balance of musicality and micro-detail level of technicality. Treble is clear and detailed, and airy, with a little extra sparkle. When switching from P to P+, it literally expands the dynamics of the sound, like inflating a ball, where the sound’s vertical dynamics expands, layering improves, soundstage perception improves, and overall sound becomes more energetic and exciting. Switching to Tube adds a little texture to the mids, a nice finishing touch.
MEZE Audio Empyrean (V44) - I hear a very wide-open soundstage with an excellent holographic imaging. Sound signature is balanced, and tonality is rather natural, transparent, revealing, not as colored as in a number of other pair ups. Bass has a deep extension with excellent textured rumble and a good mid-bass punch. Again, more weight is shifted toward the deep sub-bass while mid-bass is rounded, giving the overall bass a more laidback presentation. Lower mids have good amount of body, a little warmer, while upper mids have more focus here, bringing more attention to the vocals and extracting more micro-details. Great layering of the sound in mids, not every source can bring this out in Empyrean. Treble is clear and detailed, has a little extra crunch but nothing harsh or splashy. Good airy extension. P+ improves the dynamics, very noticeable “boost” where after hearing it you can’t go back to P. Tubes or no Tubes, it still sounds great, and I’m still undecided. I feel like SS gives mids a more even tuning and faster speed which I did enjoy more.
Beyerdynamic T5p 2nd (V39) - Another great pair up with an excellent soundstage expansion in all 3 direction and 3D holographic imaging. This was another example where P+ is necessary to scale up the sound dynamics and the soundstage expansion to its highest level. The sound is balanced W-shaped with a velvety deep sub-bass rumble, more rounded mid-bass punch. The overall weight of the bass leans more toward sub-bass. Lower mids were north of neutral, with a good amount of body and natural warmth, giving upper mids more clarity, transparency, and micro-details. Vocals came out clear, detailed, even a little brighter. There is a bit of a contrast between warmer deeper bass and brighter more revealing upper mids. Treble also has plenty of clarity, details, and natural sparkle, good airy extension. Well, I’m sure some would expect me to say that I preferred Tubes output in this pair up, but it turned out that it was the opposite. I actually preferred Solid State output. Tubes made lower mids a bit thicker to my ears, creating a bigger contract between lower and upper mids. Turning Tubes off evened out the tonality in mids, noticeable, especially with vocals. The point here, experiment with different settings.
I actually enjoyed all 3 pairs up, and as I already mentioned, found P+ to be the absolutely necessity here.
Pair up with IEMs.
Oriolus Traillii w/Chiron (V34) - Wide open soundstage with 3D imaging. Sound signature is perfectly balanced, overall tonality is natural and a bit more revealing. Bass goes deep, with both elevated rumble and stronger mid-bass impact. Mids are natural in tonality, with plenty of body in lower mids and organic detailed tonality in upper mids, quite resolving and revealing. Treble is clear and detailed, has extra sparkle and crunch in mid treble. SS gives Traillii a little brighter tonality in mids, while Tubes give more weight to low end, more body to the lower mids, and make upper mids a little smoother and even a bit warmer. I preferred Tubes mode with Traillii.
Aroma Jewel w/FT (V34) - The soundstage is wide open and expanded in all 3 directions with holographic imaging. Sound signature is balanced as well, while tonality is more neutral with a slightly more mid-forward revealing presentation of the sound. Bass goes deep, with a textured sub-bass rumble and a punchy mid-bass; the bass is tight and articulate. Lower mids are leaner which gives upper mids more transparency, less coloring, making them more revealing but not too bright. Treble is crisp and detailed, not splashy or harsh. Jewel does have a little extra resolution in treble, but it still keeps sound natural. Also, as expected, switching to Tubes gives mids smoother and more natural tonality which I preferred in this pair up.
EE Odin (V29) – For those who are interested, there is definitely no hissing in this pair up. Pitch black background with zero hissing in any gain. I was curious to try P/P+ setting, and quickly realized that P+ is a must have here, adding more weight, more impact, deeper rumble, and still keeping the bass tight and articulate. Mids are leaner, more revealing, layered, micro-detailed, but not bright and not too forward, the overall sound signature is still well balanced. Treble is crisp, clear, detailed, more revealing and yet, still well controlled and without any sign of splashiness. The soundstage is also big, expanded, holographic. Improvement in bass with P+ was impressive. Not a huge difference switching to Tubes, but it does take a bit of an edge of the brightness.
FiR Audio XE6 (V31) – A huge holographic soundstage expansion. A mildly U-shaped signature with a powerful speaker like analog bass, thanks to XE6 kinetic bass drivers, natural revealing mids and vocals which are a bit recessed, and crisp detailed treble. The XE6 kinetic bass truly benefits here from P+ setting which gives it more energy and improves articulation. Also, zero hiss, regardless of the gain or power mode setting. Tubes modes didn’t make a big difference here since XE6 tuning is warmer and smoother to begin with. But still, because of XE6 tonality, this was a perfect pair up to bring out more details and sound transparency using Solid State instead of Tubes.
Campfire Audio Solaris 2020 (V22) – Since this is Campfire Audio iem, the first question will be, does it hiss? The background is pitch black, and I don’t hear any hiss at all. The soundstage is big, with an overall sound being holographic and quite expanded. Also, the sound sig is balanced, while the tonality is brighter and more revealing. Bass has a good sub-bass rumble with a fast well controlled punch. Bass doesn't have a lot of weight, but it is for sure above neutral and unmistakably DD quality. Mids are revealing, colder in tonality even when Tubes are switched on. Surprisingly, I don’t hear any sibilance in lower treble. It is still very energetic, but the treble is not too elevated and not that fatigue. I did enjoy switching to Tubes mode, just to take an edge of its colder tonality. But the biggest improvement here was switching to P so I can enable Class A mode, and that added more body to the tuning, making it a bit more natural.
UM Mest MKII (V31) - Big holographic soundstage expansion in this pair up. Typical of Mest MKII, I found U-shaped sound signature with a deep analog quality dynamic bass where I hear more emphasis on sub-bass rumble which adds extra weight to the low end. Lower mids are neutral, giving more transparency to the sound, making upper mids more revealing and colder in tonality. Treble is bright, crisp, airy. Going between SS and Tubes helps to bring up mids a little more forward (with Tubes) by adding more body to the lower mids and slightly boosting the presence of upper mids. Doesn’t change much the treble, it is still a bit hot. I was OK with this pair up, though not very thrilled.
VE EXT (V38) – EXT does need a bit of a power boost, so I started with high gain, but quickly switched back to Medium since in high gain the upper mids and lower treble were a bit too hot. Soundstage is very big in this pair up, expanding wide and deep, along with 3D holographic imaging. Sound sig is slightly U-shaped with a bit extra emphasis on bass and treble. Bass is quite powerful in this pair up, going deep with elevated rumble and hitting hard with a very strong punch. Mids have a good balance of lower mids natural body and upper mids clarity, resolution, and details. But mids are a bit reserved and not as forward as I found EXT in some other pair ups. Treble is crisp and airy, clear and detailed. Switching to Tubes only took a bit of an edge from the brightness. I wasn’t too crazy about this pair up because I felt like mids/vocals lost some of its natural tonality and were slightly recessed.
Overall, I enjoyed pair up with most of my IEMs and was very pleased with the amount of finetuning options offered by N8ii to find a perfect pair up synergy. But to my surprise, Mest MKII treble was a bit hot and VE EXT lost some of its natural magic in mids. But Traillii, Jewel, Odin, and XE6 were shinning in this pair up.
Other Wired/Wireless connections.
In this section of the review, I will go over various wired and wireless connections I tested and verified with N8ii.
Digital usb-c out
I tested this interface using Cayin RU6 usb-dac which got recognized right away. I was using HibyMusic with Exclusive HQ USB audio access enabled, USB Audio Performance mode On, and USB Audio volume locked so it is set to the max. This way, Volume was controlled only from RU6. Sampling rate was displayed correctly. One interesting observation here, when comparing RU6 sound connected to my S22 vs N8ii, with the same cable, playing the same song, and with the same pair of iems, N8ii/RU6 has a slightly better layering and improved dynamics. I have no idea how to explain this, but I went a dozen of times, back and forth, and always came back to the same conclusion.
Coax out
With an optional Cayin usb-c to coax cable, you can turn N8ii into an audio source/transport. Just plug it in, connect to external DAC/amp, and it works right away. I was using
micro iDSD BL and everything was recognized without a problem or the need to enable anything in settings. And in this test with micro iDSD BL the sound was even better with Coax than digital out.
Line Out
Once connected to external amplifier, volume can't be controlled from N8ii, only from external amplifier.
These tests have been covered already in previous Comparison (LO test) section.
USB DAC
When connected to my Win10 laptop, in notification area of N8ii, when you swipe it down, I had to go to Android System message for USB connection and select USB preference for Audio In (usb power) or Audio In (no usb power), depending on if you connecting to a smartphone and don't want to drain its battery. N8ii was recognized right away, volume could be controlled from either laptop or N8ii. The sound using N8ii as usb dac was identical to listening with N8ii standalone.
Bluetooth Wireless
You have 2 modes of Wireless Bluetooth operation, Tx and Rx.
BT Rx - Select Bluetooth Audio in and search and pair up with N8ii from your smartphone. Enable LDAC on a smartphone and start streaming from smartphone while using N8ii as a wireless BT DAC. Volume is controlled from both, my smartphone and N8ii. Also, correct protocol (LDAC) was shown on N8ii.
BT Tx – Paired up N8ii with WH2 TWS earphones within seconds. Found it to work across 25ft of open space, full remote control from TWS earpieces. Within paired earphones setting, I selected HD audio, assuming it was referring to LDAC. Volume could be controlled from N8ii. The sound was as good as when paired up with my S22, but the BT distance was shorter.
Conclusion.
It is clear that Cayin took their original N8 DAP to a whole new level in this next gen N8ii release. The core of the design with a dual Solid State/NuTube principle is still there, now fully balanced and featuring a dual NuTube 6P1 accessible from 4.4mm BAL output. It still features a fully-discrete Dual Output power mode with P (standard) and P+ (high voltage) outputs, and adds Class A and AB amp modes (A/AB in P, and AB only in P+) found in C9. The playback-only Unix platform has been upgraded to Android 9 with Snapdragon 660 SoC and 6GB of RAM – one of the fastest Android DAP performances I have encountered based on my AnTuTu 3D benchmark tests. And the misfortune of AKM factory fire led to a discovery of a new high-end ROHM 32bit current mode DAC, available for the first time in a portable audio player, the same DAC that recently appeared in $16.5k Luxman D-10X SACD desktop player.
I was also pleased to see the updated exterior design with a more traditional playback control buttons instead of jog-dial like in original N8. The placement of both NuTube modules on the left facing outside is very clever, keeping it compartmentalized and isolated from the rest of the circuit and still visible to the user. But the most impressive part was how much tech Cayin packed under the hood of N8ii while still being able to keep it relatively portable. And, with all the additions to the design, including a pair of hi-end ROHM DACs, additional NuTube module, and other new components associated with switching to Android platform, the price of N8ii went up by only a few hundred dollars in comparison to the original N8. Of course, it’s great to have all this tech under the hood, but at the end of the day it also has to sound good.
N8ii doesn’t have a typical
Tube sound, nor does it sound lean. The sound is revealing and micro detailed without being bright or harsh and has the unique ability to finetune the pair up synergy, going from either being transparent to tastefully colored. You have the ability to switch between Solid State or Tubes/Solid State (Tubes are either enabled or disabled to give extra texture to the mids), Class A or Class AB amp mode (Class A is where you get that smooth laidback sound characteristics), and extra voltage boost going from P to P+ (doing wonders to the dynamics of DD drivers). Considering all these available tuning options, you have access to multiple
tools to finetune N8ii sound to perfection in pair up with different IEMs and headphones. And that what makes it unique and stand out from the crowd.
While the tube option is nice, I prefer solid state, AB, P+ mode for detail and resolution.