Lerian, Sam wanted to have two devices anyway, if I understood him correctly in Posting #1: an 802 or UFX II and a BBF Pro FS for mobile use. Therefore it is not necessary to discuss "UFX+ vs BBF", whether a Babyface Pro FS would be sufficient.
I brought the UFX+ into play because Sam wrote in the initial post that he would reach for a UFX II and in my opinion you should rather go for the UFX+ if you are willing to spend so much money for a recording interface anyway and if you are looking for lowest RTL (round trip latencies), which you will get by thunderbolt in the 1st place, but also by using USB3.
Allow me one comment to the RTL comparison between UFX+ and BBF Pro in post #18: please keep the same conditions, same ASIO buffersize and also same sample rate. The converter latency is more than half lower at 96 kHz compared to 44.1 kHz. Makes no sense to mix this. I used 44.1 kHz because most people are using it and this is the "worst case" in terms of converter latency. And tbh, the RTL of all RME devices - no matter whether via USB or PCIe - are so low, the differences are not that significant. Everything under 10ms is very nicely when working with virtual instruments and for simple recording purposes the RTL doesn't matter at all. There you use max ASIO buffersizes anyway for a very "save" recording.
I think features and possibilities, a variety of I/O ports and different possibilities to connect to a PC, this is more important.
If I could add one more suggestion. Depending on what Sam means by mobility, which doesn't necessarily has to go hand in hand with a small form factor, you could just as easily fit a UFX+ into a Thomann compact rack that is quite compact, because it isn't so deep (only ~23cm). By this you could perhaps save the cost for a BBF Pro FS or buy it at a later time, then you have not so high cost at once.
Sam, I assume you will have passive cooling. In this case it's recommended for a better air-flow to take 1 rack unit more for the UFX+. This is the 2 RU version of my rack: https://www.thomann.de/de/thon_rack_2he … ompact.htm
Some additional informations:
1. UFX+ (as well as UFX II) allow you to choose the same minimum ASIO buffersize of 32 samples like the PCIe cards, no matter whether you use USB2 (UFX II, UFX+), USB3 or Thunderbolt. The BBF Pro FS uses the old USB driver which uses another USB transfer mode, where 48 samples is the minimum.
2. When choosing a recording interface like UFX II and UFX+ with MADIface driver then you might also have another advantage. The application using the MADIface ASIO driver can directly access all devices which are supported by this driver (UFX+/UFX II, MADIface XT/Pro/USB, OctaMic XTC, ADI-2 Pro/AE/FS/DAC, Digiface USB). You only need to take card, that those devices are clock synchronized and use the same ASIO buffersize.
A combination that makes sense is e.g. UFX+ and ADI-2 DAC/Pro. In my setup the ADI-2 Pro FS is being clock synched by either AES or ADAT.
Both devices (UFX+ and ADI-2Pro) are connected through USB, the DAW/application has direct access to all ports of all devices and I do not have to route any channels through ADAT etc to be able to access them.
The AES (or ADAT) connection I need of course to send sound from UFX+ to the ADI-2 Pro, where Monitors / Phones are connected to.
To sum up, for my setup I identified it as an advantage to use devices, which use the same ASIO driver.
3. Also for Sam it could also be interesting at a later point in time, to add such an ADI-2 Pro FS R BE to the environment, to get those nice features of this device for monitors and phones. At least to plan, to have the option for that whenever he thinks its about the time to add the ADI-2 Pro to the setup.
Besides of quality you have also advantages from handling perspective.
The ADI-2 Pro also acts in my setup like a monitoring controller to limit the volume by having a real encoder for the volume and a feature for a slow ramp-up of volume when plugging phones or switching between monitors/phones (which can very nicely be done by using the key remapping feature of the ADI-2* to map this function to one of the front buttons.
See also this blog article about the integration of ADI-2 Pro into a recording environment:
https://www.tonstudio-forum.de/blog/ind … our-Setup/
BR Ramses - UFX+, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1650v4, Win10Pro22H2, Cub12Pro