The TR-004 comes with a USB C (on the TR-004 side) to USC A/B connection (on the PC side). Is it possible to connect instead the TR-004 from USB C on the enclosure to USB C on the PC? What sort of connection speeds can be expected if I am using a four 4 TB SATA drive raid5 disk arrangement?
C to C works as well, speed is more limited by the low power SATA/RAID controller … Users normally report around 200MB\s max on these enclosures
Some nice guy did the test before, and that might give you a reference: https://www.reddit.com/r/DataHoarder/comments/ffy4i3/qnap_tr004_quick_review_with_raid_mode_results/
From the spec of TR-004, it supports USB 3.2 Gen 1
This means no matter whether you are using the C-A cable inside or the C-C cable they both work. You just have to ensure the C-C cable is USB 3.2 compatible or the bottleneck will be that cable.
The USB sticker on the TR-004 clearly says USB 3.0. You can always connect it to 3.2 you just won’t see the added through put as the device is not capable.