This is the more technically advanced Motherboard compared to the A01, and you get a different signature, one which is more neutral but technically superior.
The sound stage is wider and deeper, the separation better, the level of precision and detail higher. You get a “higher end kind” of sound with better technicalities, especially in balanced mode. The presentation is spacious, airy and open and gone is that more intimate approach. The T01 and N6ii combo extends better in the lows and highs but it does no longer have the same thickness and full bodied presentation of the A01 module. The delivery still is musical but it is lighter and more neutral.
Bass is tight and fast and has a really nice kick but it doesn’t have the bigger body compared to the original Motherboard. The depth and layering is good, especially in balanced mode. It’s the more neutral kind of bass presentation, but one with way better layering and detailing. The sub bass on the A01 might be better though.
The mids share the same characteristics as the bass and it is fast, precise and energetic. Cayin was smart to mix it up with the right amount smoothness, resulting in a technically higher, yet still musical approach. The mids are spacious, dynamic and have great detail retrieval.
The treble section fits in perfectly with the bass and mids and it is more clear, extends better and has more detail with the T01. It’s energetic, more spacious and delivers more detail. Out of the first two Motherboards, this is the one I personally like most as it’s technically the strongest while remaining musical.
With the E01 in Class A mode, you get a warmer presentation but it’s a fairly linear/balanced from top to bottom. The E01/A doesn’t boost any frequencies and it body-wise has a neutral tuning, this goes for bass, mids and treble. The delivery is very clear and the separation and detail retrieval is excellent.
The bass is tight, fast and has a nice kick like with the T01 motherboard. It’s sparkling, clean, fast and and tight. The mids are nicely spacious and have good separation, the mids are the widest sounding in this “mode”, while the treble is energetic and lively. Treble doesn’t extend very far though. The technicalities of the E01/A board are good and I quite like this presentation, where the bass is tight and the mids are lush.
With the Class AB mode, the N6ii & E01 shifts up a gear. It delivers more overall body, a wider sound stage, better dynamics, extension and decay. The overall layering and timbre also becomes better and this simply is a technical very strong “mode”. At the same time the delivery is always very clean and tight but musical. So what’s not to like? The biggest difference is probably in the treble section which becomes more energetic and lively, while extending further on top of all that. The vocals like in Class A mode or maybe a bit more forward but it doesn’t disturb me in any way, as it helps with the liveliness and energy factor. With this Audio Motherboard, the E01 with Class AB amplification sound best.
The effect of the dual ES9038EQ mobile DAC chips and a the class AB discrete amplifier is immediately audible. This is the cleanest, widest and most airy sounding Motherboard, with lovely extension, impressive layering, natural spaciousness, great detail retrieval/clarity and an addictive timbre.
The E02 sounds powerful, energetic and lively, but it also has a slightly smooth delivery in the mids and treble, resulting in a high level musical sound with lovely extension. The depth and layering from bass to treble is impressive and exemplary.
Bass reaches low and has good detail, layering and impact. It body-wise also is very nice: slightly more than neutral but never too much, the way most people like their bass.
The natural timbre mids are really good: spacious and airy with excellent separation. The presentation is airy and extended, with awesome decay. The depth and layering are also really good. Body-wise the mids connect perfectly to the bass and with the slightly forward vocals the N6ii / E02 sounds engaging, musical and addictive.
The treble section is lively and energetic enough to contrast the nicely bodied bass and mids. Treble extends nicely, shows great layering and is spacious but it isn’t the most energetic treble at the same time. For me it could be a bit hotter, but that’s personal preference.
R2R tech for the moment is hip again, especially in DAPs. Luxury & Precision has delivered some of the finest examples of high end R2R portable players, and as such we’re not surprised at all to see Cayin come up with an R2R board as their fifth mother board for the N6ii.
I personally like the R2R sound. Sure they might not measure well or they are difficult to measure, but cares about the numbers if it sounds good. Right? The downside of this card? No line out, but I can live with that.
The Cayin N6ii and R01 combo is technically strong. You get excellent detail retrieval, great PRaT, top level separation and jaw dropping timbre. The clarity, layering and depth are equally impressive. The sound stage is good both in width and depth, but especially the depth is impressive. The R2R board sounds natural and it has a realistic amount of air and spaciousness from the highs to the lows. It’s really precise, but it’s also easy on the ear, making it completely non-fatiguing. This motherboard to me elevates the Cayin N6ii DAP to new highs, which we haven’t seen before. Yes the other boards were good and had their own characteristics, but this board is the one that rules them all (if you don’t need a LO). Oh yes, it’s that good.
Positioning and stereo image, especially with a top level IEM such as the UM MEST 2, is super impressive. It’s not easy to impress me anymore, but this combo sure does the trick. The E02 is really good, but this is simply better if you ask me.
Bass is clean, tight and has really good impact and punch. It’s not overpowering but present when needed. In example Billie Eilish kind of bass will show up strong. No matter how strong though, bass is always perfectly in control and you get all the detail there is, combined with excellent depth and layering. Sub bass (again, try Billie) is addictive. The mids section is realist, clean and naturally spacious. The delivery is smooth and musical, not to be mistaken with warmth. Vocals blend in perfectly and they’re not being pushed to the front or getting a more aggressive push. It’s all smooth and natural. The treble section is very clean and has enough energy to make and keep things exciting, but it’s not the most spicy. It’s a top level kind of treble, which has all the detail and extension, without being harsh on the ear. I would be surprised if someone would describe this treble presentation as sharp or hot. Yes it could have even more energy and extension, but the way it is now matches best with the overall tuning.
There’s absolutely nothing I don’t like about this card. No it’s not cheap, but it brings you a whole new N6ii DAP which you will easily enjoy for another year or two. What’s not to like?
Six different Audio Motherboards, with no less than six (duh) different sound signatures. In the very beginning we weren’t sure what Cayin’s plans with the N6ii were in regards to customization, but they clearly weren’t kidding when they said a whole series of boards would follow. The fact that other high end brands are now doing the same (again) shows that Cayin made the right choice doing so.
As far as we know this is the last of the motherboards Cayin will release, but never say never. And in case they don’t, the N6ii for sure is a success story, with a fem more years of life left in it.