Cayin RU7: 1-Bit Resistor Network Dongle DAC /Amp

[oldkid]

Nope, if you look at the functional diagram, the 4 channels are designated as L+, L-, R+, and R- repectively, which mean they are the regular stereo channel and their corresponding negative phase. We describe this design as differentiate DAC, and they are completely different from multichannel DAC.

Yes, I saw the diagram after posting my question. Basically, RU7 is a true balanced DAC, unlike RU6.

 

[Andykong]

RU-6 reminds me of compression used on vinyl mastering to avoid excessive groove excursion with biggest impact on
low bass. Sound is musical but you can hear the loss compared to a desktop DAC or battery powered DAC.

Not detecting where that will improve with RU-7?

Yes, the RU6 is never meant to be used or compete with desktop DAC product. I have no idea why users are doing thatso frequently.

Cayin sells desktop DAC and DAP, why woukd we make a Dongle to compete with our own products? I suggest we remain realistic when we are satisfied by tge RU6 and RU7 performance.

Having said that, when used with the right source and IEM, one shouldn't feel compressed or roll off. There are limitations in the quality of the product due to size and cost constraint, but your observation is new to me.

 

[zolom]

Any sound comparison with the RU6?

Thanks

 

[ThanatosVI]

Yes, the RU6 is never meant to be used or compete with desktop DAC product. I have no idea why users are doing thatso frequently.

Cayin sells desktop DAC and DAP, why woukd we make a Dongle to compete with our own products? I suggest we remain realistic when we are satisfied by tge RU6 and RU7 performance.

Having said that, when used with the right source and IEM, one shouldn't feel compressed or roll off. There are limitations in the quality of the product due to size and cost constraint, but your observation is new to me.

I heard both dongles at the high End, and they are both mighty impressive for the price.

I preferred the RU7 for its bigger stage and smoother presentation while my brother preferred the RU6 since it sounded more impactful and energetic.

Both were a huge upgrade to the outputs of our Smartphone

 

[oldkid]

I heard both dongles at the high End, and they are both mighty impressive for the price.

I preferred the RU7 for its bigger stage and smoother presentation while my brother preference the RU6 since it sounded more impactful and energetic.

Both were a huge upgrade to the outputs of our Smartphone

Smoother than RU6 is like smoother than butter in terms of audio. Can't wait !

 

[Andykong]

Maybe RU7 can get DSP eq? That little display is perfect for editing some eq bands...

RU7 does not built-in any kind of EQ feature. If you need DSP EQ, you need to do this in your source, i.e., mobile phone, tablet or computers.

If you prefer a Dongle DAC with built-in EQ, your best bet is similar product that employs DAC chipset with imternal EQ. Dongle DAC are too small to include MCU or FPGA, so adding EQ outside DAC chipset is not practical.

 

[emilsoft]

RU7 does not built-in any kind of EQ feature. If you need DSP EQ, you need to do this in your source, i.e., mobile phone, tablet or computers.

If you prefer a Dongle DAC with built-in EQ, your best bet is similar product that employs DAC chipset with imternal EQ. Dongle DAC are too small to include MCU or FPGA, so adding EQ outside DAC chipset is not practical.

Not sure how Qudelix 5k manage to fit in a 20band parametric eq in their tiny dongle for 100$ - i'd be more than happy to pay extra for a more exotic sound quality with this feature. I sold my RU6 as I had no elegant way to adjust it a little for my headphones (I use apple music, so no eq on source ability). In terms of DAPs Hiby have convolution plugin which offers very flexible global eq ability. I'm hoping one day Cayin will embrace this (eq) as a very important feature when it comes to headphone listening with their DAPs and dongles in the future..

 

[emilsoft]

I wonder how the RU7 measures? The RU6 was atrocious - bordering on broken, measurements wise. 0.1% resistors (typically 0.05% required for decent engineered dac) + lack of any good feedback correction network (like Hiby Darwin) translated to audible unwanted artefacts. Nevertheless it had a pleasing tonality and R2Rness but with large side effects - kind of like a retro R2R dac from the 80s in a dongle form.

edit:
* Seem it measures quite well, much better than RU6: https://www.head-fi.org/threads/cay...rk-dongle-dac-amp.968064/page-7#post-17563945
I wonder what difference do 0.05% vs 0.1% resistors for this kind of 1 bit network (RU6 couldn't recreate a basic triangle wave @ 220.5Hz properly)

 

[ClieOS]

Not sure how Qudelix 5k manage to fit in a 20band parametric eq in their tiny dongle for 100$ - i'd be more than happy to pay extra for a more exotic sound quality with this feature. I sold my RU6 as I had no elegant way to adjust it a little for my headphones (I use apple music, so no eq on source ability). In terms of DAPs Hiby have convolution plugin which offers very flexible global eq ability. I'm hoping one day Cayin will embrace this (eq) as a very important feature when it comes to headphone listening with their DAPs and dongles in the future..

Via its Qualcomm Bluetooth controller chip, which happens to be have a dual cores 120MHz processors and DSP function built-in, thus giving it the necessary processing power for PEQ. You will probably need something on the same level as XMOS controller chip on a USB dongle to do PEQ, but that usually end up sucking up a lot of power from the source.

 

[emilsoft]

Via its Qualcomm Bluetooth controller chip, which happens to be have a dual cores 120MHz processors and DSP function built-in, thus giving it the necessary processing power for PEQ. You will probably need something on the same level as XMOS controller chip on a USB dongle to do PEQ, but that usually end up sucking up a lot of power from the source.

Would it be feasible for Cayin to use the same bluetooth controller chip for their dongles? Even if they turn off say the bluetooth functionality and only use it as a 96khz usb controller (as eq also works over usb).. I assume it's relatively cost effective considering Qudelix dongle is only 100$.

 

[ClieOS]

Would it be feasible for Cayin to use the same bluetooth controller chip for their dongles? Even if they turn off say the bluetooth functionality and only use it as a 96khz usb controller (as eq also works over usb).. I assume it's relatively cost effective considering Qudelix dongle is only 100$.

Cayin has been trying to make their USB dongle unique with not-off-the-shelf DAC implementation. Using a BT chip with it's very limited USB function, while not impossible, is kinda impractical. Besides, USB dongle is usually paired with smartphone, which has much more powerful powerful processor that can do PEQ easily on the app level

 

[emilsoft]

Cayin has been trying to make their USB dongle unique with not-off-the-shelf DAC implementation. Using a BT chip with it's very limited USB function, while not impossible, is kinda impractical. Besides, USB dongle is usually paired with smartphone, which has much more powerful powerful processor that can do PEQ easily on the app level

Their dac can still be not-off-the-shelf, we are talking about the usb controller here - there is nothing much very usb limited about the BT chip in question here, the only limitation is 96khz from what I understand - Qudelix works perfectly fine on any usb devices, from phones, laptops, streamers.

As I mentioned eq on source can be tricky or impossible - I use Apple music and that has no EQ ability, and i can't use global EQ on my phone... Also Qobuz on iphone doesn't provide EQ, and I have no other way to run it.

I don't buy into the technology limits excuses, There's other tiny low powered fpga/chips that can be used (the tiny L&P w4 dongle also have eq ability - albeit presets non user editable)

I'd much prefer just a simple answer of they don't have the budget/scope/team to do DSP based processing with good UX.. I hope they change this stance soon, things are moving fast nowadays and DSP is more common, even Fiio with their BTR7 have done a nicely flexible EQ and will be doing more devices with that architecture.

 

[ClieOS]

Their dac can still be not-off-the-shelf, we are talking about the usb controller here - there is nothing much very usb limited about the BT chip in question here, the only limitation is 96khz from what I understand - Qudelix works perfectly fine on any usb devices, from phones, laptops, streamers.

I don't buy into the technology limits excuses, There's other tiny low powered fpga/chips that can be used (the tiny L&P w4 dongle also have eq ability - albeit presets non user editable)

I'd much prefer just a simple answer of they don't have the budget/scope/team to do DSP based processing with good UX..

The fact that Qualcomm chip is limited to max 96kHz is not exactly a great selling point to explain to your customers when they are paying you hundreds of dollars for an supposedly very advanced USB dongle just so PEQ can be implemented in the USB dongle where it can also be much easily done via app.

Sure if sky is the limit then you can implement whatever you want on a USB dongle, but it doesn't mean others will find it to make as much commercial sense as you do.

 

[emilsoft]

The fact that Qualcomm chip is limited to max 96kHz is not exactly a great selling point to explain to your customers when they are paying you hundreds of dollars for an supposedly very advanced USB dongle that can't just so PEQ can be implemented in the USB dongle where it can also be much easily done via app.

Sure if sky is the limit then you can implement whatever you want on a USB dongle, but it doesn't mean others will find it to make as much commercial sense as you do.

I disagree - first of all something like the RU6 can't make proper use of anything above 44khz 16bit rate due to it's architecture and low accuracy resistors (0.1%).. now the RU7 perhaps might arguably be able to I can't say as I don't understand the architecture, but the benefits of DSP far outweight the SQ improvements above 96khz sample rates which are arguably not even audible on a dongle. Even Genelec/Neumann admit to downsampling to 48khz on their $$$$ over engineered technical marvel DSP monitors used to produce large quantities of audiophile music in top studios nowadays - anyhow this is a different discussion.

As for commercial sense - a simple market research shows that DSP eq like the one in a Qudelix 5k dongle is widely adored and is a key factor in sales - my simple market research on Amazon shows over 1400 positive ratings for the Q5K. Check any other dongle ratings on Amazon you will see at most couple of hundred ratings.. taking into account Q5K's sound quality is nothing world shattering (at least compared to other dongles) leads me to deduce that it's great DSP is the key factor in sales. Now imagine upping the sound quality like Q5K on steroids (perhaps the RU7) and you have a blockbuster.. instead we get a new dongle every few months which has some tweaks but does mostly the same as the previous dongle (like new mobile smartphones every year)

 

[Daiyama]

I wonder how the RU7 measures? The RU6 was atrocious - bordering on broken, measurements wise. 0.1% resistors (typically 0.05% required for decent engineered dac) + lack of any good feedback correction network (like Hiby Darwin) translated to audible unwanted artefacts. Nevertheless it had a pleasing tonality and R2Rness but with large side effects - kind of like a retro R2R dac from the 80s in a dongle form.

edit:
* Seem it measures quite well, much better than RU6: https://www.head-fi.org/threads/cay...rk-dongle-dac-amp.968064/page-7#post-17563945
I wonder what difference do 0.05% vs 0.1% resistors for this kind of 1 bit network (RU6 couldn't recreate a basic triangle wave @ 220.5Hz properly)

What are these audible artefacts? Do you have an example were this audible? I would like to know if I can hear such things also or if I am deef to such artifacts.
Thank you!