Cayin RU6 USB DAC Headphone Amplifier

Product Information

Again, the bass doesn’t hit very deep so it takes away some of the depth yet it works well for studio-recorded tracks and small ensembles. That is, the phase distortion and jitter remain at a very low level with no artifacts in the output signal. By the time Cayin completed the R01 Audio Motherboard for the N6ii DAP, they noticed that the R-2R resistor ladder network could be implemented as a low power consumption DAC circuit that offers outstanding audio performance.

Due to the way the R-2R circuit is designed, there are moments where the volume with quickly pause and pop. This is evident when tested with Etymotic ER4SR and Shure KSE1500, my most trusted reference listening devices that will reveal the nature of the source truthfully. I love to travel, never in one place for a long time though a bit hard these days due to the pandemic. As for battery consumption, I have measured my RU6 on Sony Xperia X Compact (Android 8, 2700 mAH, UAPP bitperfect mode, Low Gain driving TRN VX Pro) and the results yielded 6 hours of continuous play by the time the battery reached 3% (from 100%). Timbre is utterly natural and so close to reality that in the end you forget about the technicalities as you are immensely drawn to the music, song after song as the time passes by without noticing.

With Delta Sigma audio processors, what I am hearing today is sound presentation that is very clean, detailed, resolving and analytical - and I can understand that many love it that way.

One of the achievements that surprised me most is that RU-6 drives successfully not only demanding iems but also demanding headphones - it drivers perfectly the Z1R iem but also the Z7M2 headphones, it also drives very well the P1 but also even the T60rp (for the headphones I used the 4. Bass hits strong with a great authority, and I hear a deep sub-bass rumble; mids/vocals are clear and detailed, a bit more revealing; treble is crisp and clear, on a brighter side but with zero fatigue. RU-6 value is its naturalism of replay and presenting the flavor of R2R w/o dropping technicalities.This architecture minimises power drain from the mobile source allowing you to enjoy music without the need to worry about battery drain. Instead of building RU6 on the common DAC chips widely available out in the market now, Cayin opted for the much more complex R-2R design which was adopted from their highly regarded R01 Module for Cayin N6ii. I prefer non-oversampling mode to give it the special sauce that makes this DAC a little unique compared to the competition. That surely improved the sound with deeper sub-bass and beefier mid-bass, more body in mids, and overall, more natural balanced sound. It is Cayin's first ever DAC/Amp in Dongle form factor and most importantly, it is the very first non Delta Sigma Dongle ever.

However, when it comes to sound - it just lacks the iFi signature clean sound and also sounds quite thin when compared to others so far.With the midrange being quite forward and the very low end being quite shy, staging is stretched wide. RU6 was connected to my Galaxy phone with volume set at the max (on the phone), and I was using HibyMusic app. As follow up to their R01 N6 II module, the company is introducing the RU6 that features a shrunken down derivative of the same R-2R DAC. balanced jack of the RU6, switched on NOS mode, and was playing music out of Roon from my desktop PC. I’m sure most are aware of the R-2R DAC movement but for those that aren’t, these DACs differ entirely to those widely adopted on the market such as AKM and ESS, commonly dubbed Sigma-Delta DACs.