The detail description of our Type-C to RCA coaxial cable are as follow:
http://en.cayin.cn/products_info?itemid=101
You can buy this cable through your local Cayin dealer. Some of our dealers might not keep a regular stock on this cable because it is a specialized cable to bridge between our DAP with desktop product, but you should be able to place order with them. The cable is retailed at US$59. It might sound a bit expensive when consider the N3 is only US$149.99, but please be reminded that this coaxial cable will be used by all Cayin DAPs since 2016, so we have to make sure its is a decent cable for different price segment and is good enough to work with wide range of external DAC products. Cayin has gone through 4 rounds of prototype before we can find the lowest cost solution to build the Type-C to RCA Coaxial cable . We start with a lower budget and gradually works our way up in order to get something that works well, I have enclosed the first and second prototype for your reference:
Cayin make these cable to expand the connectivity of our DAPs, we hope our customers can utilize their DAP to full extend, we do make profit out of the cable, but not significant when you consider the MoQ and operation overhead required to deal with these cables, and I believe we are not on the expensive side when compare to other after-market cables.
For the benefit our our DAP users, we shall disclose the pin-out of the USB Type-C, and I can provide the basic instruction for your reference. We welcome users to DIY their cable solution if they have the resource and time for that, so here we go:
This is the standard pin-out diagram of Type-C, pin A8 and B8 are NOT USED for USB, so they are not allocated in normal application, and Cayin used this pin to transmit S/PDIF signal.
Normal Type C connectors are extremely difficult to because the pin are hided inside the connectors, and they were designed to factory fit by automated machines. You need to find special connectors that has all the pins extended to a small PCB. Make sure you check with the seller that pin A8 and B8 have been extended to the PCB before you pay for it, because these two pin are not used for USB, quite a lot of custom connectors will ignore these two pins.
Once you find the appropriate connector, the first thing you should do is to hard wired between A8 and B8, as illustrated below:
Then you should prepare your coaxial cable as follows, around 1.5cm bare connectors should be good enough for subsequent jobs. If you are new to DIY, we recommend you to cut off one RCA connector of a ready-make coaxial cable for this project, this will make sure you have the right kind of cable and you only need to work on one connectors, with the RAC connectors untouched. We also suggest you to put a heat-shrinkable tube into the coaxial cable before you start the soldering work.
You can now solder the coaxial cable to the A8 pin, and then the ground shielding to the ground pin of the PCB
Just heat up the heat-shrinkable tube to protect the connector, or better still install a USB connector cover if you can find that as well.
This cable is finished and ready for testing: