Cayin - RU6

Hi all
I bought cayin RU6 because I wanted to test the R2R technology.
The dongle is very well built. The type C poty, the chasis, the SE and balanced ports look premium. The matte finish of sides and back, glass front, the metallic line along the sides - all look very good. This is a sturdy device. The buttons are kept at horizontal orientation to the sides rather than conventional parallel orientation. They work perfectly.

Connection was easy. Just plug and play.

Setting- three settings. Gain - high/ low, sampling - OS/ NOS. OS is oversampling, which makes the sound slightly warm and add more flavor to it. NOS is slightly boring but detailed. Last is screen backlight timing. These can be changed just like looto paw.

Sound- Accurate and lively. Details- its NOT one of the most detailed dongle DAC. That accolade belongs to Looto paw s1 and L&P W2.
Soundstage- definitely one of the largest, if not the largest among dongle dacs.
Localisation- average. Sound notes mix together and less separation among instruments. So pin point accuracy of instruments on soundstage not possible.
Highs- they are well represented.
Mids- Lush and full vocals. Both male and female vocals feel very good. Its not mid-forward presentation but gives perfect representation.
Bass- very good, solid bass with good sub-bass and reverbs. Not the fastest like A&K dongle. But still very well regulated. Slight bass bleed to the mids.
Power- good for iems. Not for power hungry cans but its understandable.

Tonality- here W2 and DAPs like ibasso dx160 and m11 plus are slightly ahead. Overall very good DAP like tonality compared to many other dongle dacs available in market.
Timbre of instruments- its accurate and lifelike

Competition- L&P W2 is priced similarly. Both are good. W2 slightly ahead in SQ but background noise in W2 is more while streaming.
Its ahead of looto paw S1 and A&K dongle in terms of tonality and presentation.

Overall verdict- if you wamt to experience R2R technology, this thing doesn't disappoint. Good organic warm sound with good technical capabilities. It'll be among top 5 dongle DACs definitely.

Tried with both IOS ( iphone 11) and android LG G8x.
Initial impressions: no regrets
Probably the best usb dac in market right now.

Currently using - Earmen sparrow and LP W2. This is definitely a good addition to them

Using to drive primarily IER Z1R , UM MEST MKii , IMR EDP+

Excellent tonality and bass. Widest sound stage you can get through a USB DAC till now.

Really impressed. As many say it requires some burn in, hope it may open up better and settle on treble.

Pros
1) Natural sound signature that is forgiving of even low resolution mp3 files but scales well with hires files.
2) Quite holographic soundstage and good imaging capabilities
3) Very dynamic sound signature with great bass thump and impact
4) Treble is detailed but not sibilant or overly sharp
5) The least expensive R2R Dac out there in the market
6) Powerful enough for almost any iem in the market

Cons
1) Not a truly balanced circuit despite the 4.4mm port
2) Rare instances of EMI interference noises
3) Volume changes can sometimes be a bit slowdue to the switching relay resistor volume control

My Setup
Smartphone: Oneplus7Pro
Apps used: USB Audio Player Pro (bit-perfect playback with Tidal and Qobuz integration), YouTube vanced, Apple Music
Iem used: 7hz Timeless through the 4.4mm port

First of all thanks to Headphonezone for bringing this unique product to the Indian market. The USP of this product is that this is the world’s first R-2R Dac in dongle format. R-2R Dacs are generally known for their more natural sound signature and huge difficulty involved in engineering one correctly as precise resistors have to be hand selected and arranged in ladder format. This Cayin RU6 uses 96 precise resistors in ladder form for 2 channel audio.

The combo of Cayin RU6 plus 7hz Timeless produces a highly dynamic, engaging, and wide sound signature. The naturalism of the R-2R Dac especially helps in adding more midrange lushness to the sound signature of the 7hz Timeless compared to my Hiby R3 Pro Sabre Delta Sigma-based DAP which I used earlier. The soundstage also gained a more holographic nature with the Cayin RU6 compared to the Hiby. Songs such as ‘Thriller’by Michael Jackson, ‘Jack Sparrow’ by Royal Philharmonics Orchestra as well as ‘Doors and Distance’ by Antonio Sanchez illustrate the soundstage capabilities of the RU6. ‘Chali Kahani’ from Tamasha gives a clear illustration of the great dynamics of RU6.

A note on value for money: This is priced at the Summit Fi range of dongle dacs at the moment and encroaches upon the price category of a Mid-Fi Dap such as Shanling M3X. I would say that for anyone ok with carrying a dongle with their smartphone, RU6 is a great value for money product especially when you consider the high-end and niche tech inside as well as the highly natural and engaging replay of music offered by the RU6.

So, let me start by saying that Cayin is a pioneer in making audiophile geeky sorta gear. This little guy lets you switch between 2 modes making it super convenient. The screen is super clear, conveys information perfectly fine.

The Cayin RU6 is equipped with an R-2R DAC that is in producing a really natural sound. It’s extremely small & easy to use so no complaints there. The player also lets you switch from (NOS) to oversampling mode easily scrubbing any last bit of distortion. A cherry on the cake is that this dongle is backed up by a low power volume control solution. Thank you headphone zone for the fast delivery!!

R2R DAC in such a small form factor is insane. It sounds incredible. In the space of compact dongle DAC the RU6 definitely shines and provides insane value for money.