Pick a card, a modular card!

PROS: natural musical tonality, modular DAC/amp design, Snapdragon CPU w/4GB RAM, fast Android interface, 4.4mm BAL Headphone and Line Out, 5900mAh battery with extended playback time.

CONS: price, additional cost of new DAC/amp cards.

The product was provided to me free of charge for the review purpose in exchange for my honest opinion.

Manufacturer website: Cayin. Available for sale on MusicTeck and Amazon.

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Intro.

Another DAP, another review? Well, maybe not just another DAP. Cayin decided to do something different to make their product stand out from the crowd. I have been using the word “crowd” a lot lately because DAP field is crowded (more like overcrowded) with lots of new releases. And on top of that, it’s hard to miss a wide price gap between flagships where the price is no longer the indicator of DAP’s superiority.

So, how do you stand out from the crowd where even mid-fi audio players use premium AKM and ESS DAC chips? Of course, we all know that it’s not about what you use but how you implement it, and that comes from years of design experience. But the audiophile enthusiasts constantly demand more, driving manufacturer to push the envelope further. Thus, Cayin decided to up their game and to introduce a DAP with a modular design where you can replace the whole audio motherboard which hosts a DAC and an amp.

While typically a replaceable amp module (just like an external amp) affects the coloring of the sound, the idea behind N6ii audio motherboard is to let you replace a combo of DAC and amp in order to change the signature of the DAP. Hopefully when the next audio motherboard card becomes available, I will be able to test this sound change. But in a meantime, after spending a month with N6ii, let me take a closer look at this new Cayin DAP with its default A01 card.

Unboxing and Accessories.

As expected, and seen in many Cayin release, they put some extra effort into creating a premium packaging with a cool unboxing experience.

Also, Cayin included quality usb-c data/charging cable, tempered glass screen protector, 2.5mm (female) to 4.4mm (male) right angled short adaptor (the same as in N8), a very detailed printed manual booklet, and a leather case. Btw, leather case has a nice secure tight fit, but not exactly the same high quality as Dignis or MITER cases which I hope to see one day for N6ii.

The case.

Design.

Once out of the box, the first impression was how solid N6ii felt in my hand. The main front focus is around 4.2″ IPS (768×1280 resolution) screen, and overall dimensions are relatively compact at 121x70x21mm, though it is thicker than some other DAPs due to a bigger battery and assuming a sliding mechanism for internal audio motherboard. It’s not too heavy, but you do feel a nice heft of its 290g. With a smooth sandblasted CNC aluminum chassis and glass back, I would strongly recommend keeping it in the included leather case to enhance the grip.

The display placement is asymmetric with a thin left and top bezel and extended beveled right and bottom bezel. Under the visible portion of the display screen you have an outlined soft HOME button (tap for Back, hold for Home screen) which also has a breathing light LED circle when charging. Left side of chassis toward the bottom has spring-loaded micro SD card slot, tested and confirmed by Cayin to work with the latest 512GB cards, while internal storage is 64GB. At the bottom you have I2S digital port (mini HDMI Type-C to interconnect with compatible devices), USB port for charging, data transfer, and a digital transport interface, including S/PDIF coax cable connection when using Cayin custom USB-C cable (common with other Cayin DAPs).

Right side of the DAP has hardware playback buttons with Play/Pause in the middle and Skip above and below it. Toward the upper right corner, you will find a Volume wheel with protective guards allowing access to the front and the back of the wheel. The volume wheel is easy to control with a thumb or an index finger, has a soft click feedback as you rotate it, a little mushy, and sometimes requiring two clicks to change a volume by a step (per review sample I received). It also has Push-button functionality as a Power button where you short press to turn the display on/off and long press to turn the power on or to bring up Android pop up for shutdown. The guards around the wheel protect it from accidental pressing when in the pocket. Overall, I find it very convenient and efficient to be able to control volume and display/power with a single button, using only a thumb.

Under the hood.

The top of the DAP hosts a replaceable Audio Motherboard card with 4.4mm BAL headphone port (530mW @32ohm, 1.2ohm OI, 121dB SNR) which can be selected as Line Out or Phone Out. Next to it is 3.5mm SE headphone port (245mW @32ohm, 0.6ohm OI, 119dB SNR), and a separate 3.5mm Line Out port. Each Line Out level can be adjusted. On the back at the top, there are 2 small screws which hold the Audio Motherboard in. The default stock A01 card comes with AK4497EQ 32bit DAC, quad OPA1622 op-amps, and other miscellaneous components. The rest of the common circuit is on the printed wiring board inside the main chassis, including low jitter clocks (covering 3 fundamental frequencies) and DSP FPGA dedicated to DSD/PCM signal processing with a support of many popular lossy and lossless formats up to PCM 32bit/384kHz and DSD256.

Thanks to Snapdragon 425 CPU and 4GB of RAM, the Android Oreo (8.1) performance is very fast, pretty much identical to Hiby R6Pro, including implementation of DTA (direct transport audio optimization to bypass SRC sample rate conversion of stock Android) which ensures playback from all the apps without re-sampling. Along with optimized Android OS, you will also get pre-installed Google Play, HibyMusic app, and Cayin’s own Music app based on modified HibyMusic. With Google Play you can download any app, and within minutes I was streaming Spotify and playing YT videos. Furthermore, you will find support of 2.4G/5G dual WiFi bands and Bluetooth 4.2 with LDAC, aptX, and AAC, enabling the use of N6ii as a wireless BT DAC. Not the latest BT, but as long as LDAC is supported, I’m OK with it. HibyLink Remote control is supported as well.

I already mentioned that N6ii accommodates a bigger battery, 5900 mAh, which is quite impressive for an average size DAP. For me personally, the battery performance of N6ii is one of its strongest Pros. With WiFi off, playing 320kbps mp3s from 3.5mm SE output in mid gain, I was able to get close to 14hrs of advertised playback time. Switching to 4.4mm BAL output in mid gain while playing hi-res lossless FLAC files, I was getting over 12.5hrs of playback time. The standby time with WiFi and screen off was impressive as well, but once WiFi is enabled it drains a little faster, as expected from Android device with all its background processes. Furthermore, there is a support for Quick Charge QC3.0 (with appropriate charger) where you can expect to reach the full capacity in about 2hrs.

Page 2 – Sound analysis and Pair up.
Page 3 – Comparison and Conclusion.