If you go to the Focusrite website, make sure to read the fine print on their Windows Thunderbolt support.
https://global.focusrite.com/downloads?product=Clarett+8Pre
 
"Known issues:
- Glitchy audio/enumeration issues when using Thunderbolt 3 connections via an adapter. Please note that Thunderbolt 3 connectivity is NOT yet supported.
- Cubase 8.5 crashes after the save when closing down a project with MIDI tracks.
- Driver installer optimisations"
 
 
Antelope does not currently offer Thunderbolt (Windows) drivers for any of their audio interfaces.
 
As I mentioned above, if you're looking for PCIe level performance (under Windows), you've currently got three choices (MOTU, UA, RME)
 
 
 

Not sure what's happening, my 2nd answer was deleted. Here it is again, hope it won't appear as duplicate.
 

Jim Roseberry
 
To my knowledge, only three companies have "PCIe via Thunderbolt" drivers actually available for Windows.

• MOTU with their AVB series
• UA with the newer Apollo series
• RME with the Fireface UFX+

 

 
Focusrite has TB drivers for Windows in beta for the Clarett line: [link=https://support.focusrite.com/hc/en-gb/articles/213525925-Clarett-Windows-Getting-Started]https://support.focusrite...indows-Getting-Started[/link]
 
TB3 PC to Clarett via adapter: driver in preparation, does not work yet.
 
I don't understand what you say about TB2. You will be perfectly able to drive a TB 1/2 audio interface from a TB2 PC, as long as drivers are available.
 
TB3 to TB2 is not guaranteed, as the port is physically different. However, some TB3 + TB2 adapter do work, if not officially, see my post above.
 
For an example of TB3 PC to TB2 audio interface that works (with Apple 30$ TB3-TB2 converter), see https://youtu.be/9fdM9j70PSc
It's a NUC to UA Apollo.
 
 

FWIW, Your post is lacking some important details.  
 
ANY audio interface that is running under Windows via Thunderbolt-2 is running "Firewire protocol via Thunderbolt"... not "PCIe via Thunderbolt".  
 
Microsoft does not support "PCIe via Thunderbolt" for Thunderbolt-2 (only Thunderbolt-3).
 
Using the link above... to the Focusrite Thunderbolt "Clarette Windows || Getting Started" page:
Notice the ASIO buffer size is 64-samples... and the (relatively) high round-trip latency.
That's because the driver isn't running "PCIe via Thunderbolt".  
It's running "Firewire protocol via Thunderbolt".
Does it work? yes... (performance similar to connecting via Firewire controller card)
Does it offer PCIe level performance? Absolutely not.
 
Someone looking for a Thunderbolt audio interface is most likely looking for PCIe level performance.
17.4ms total round-trip latency at a 64-sample ASIO buffer size is not what this person is seeking.
 
 
 

Duplicate post

Jim Roseberry
FWIW, Your post is lacking some important details.  
 
ANY audio interface that is running under Windows via Thunderbolt-2 is running "Firewire protocol via Thunderbolt"... not "PCIe via Thunderbolt".  
Microsoft does not support "PCIe via Thunderbolt" for Thunderbolt-2 (only Thunderbolt-3).

Can you please post links to sources that confirm this?
 
Have you looked at the videos linked ?
UA Apollo TB works really well with both a TB2 Windows computer and a TB3 Windows computer, at least with pro tools.
 
I found an interesting & long thread on Gearslutz on TB support in Windows 10, with someone from Microsoft participating. I'll read it in full, at the latest this weekend.
 
Cheers
https://www.gearslutz.com...port-windows-10-a.html

Look at the control panel picture I posted above for the Clarett.
Look at the total input/output latency.
There's no way that driver is running "PCIe via Thunderbolt".
Yes, it works... but it's offering nothing similar to PCIe level performance.
Actually, that's poor performance compared to a USB-2 audio interface.
ie: RME Fireface UFX yields 4.3ms total round-trip latency at those same settings.
 
Microsoft doesn't support "PCIe via Thunderbolt" for Thunderbolt 2 controllers.
Read the thread on GS.  
 
The original UA Apollo does work connected to a Thunderbolt-2 port.
BUT... it's running "Firewire protocol via Thunderbolt"... not "PCIe via Thunderbolt".
 
Directly from the UA Website:

"Thunderbolt for Windows is here!

As of UAD v9.0.0 (available here), all UAD Thunderbolt devices are compatible with Windows 10 PCs that have built-in Thunderbolt via USB-C.* For compatibility details, please see the articles for your device below.
*Note: A qualified Thunderbolt 3 to Thunderbolt adapter is required. See the links below for more info."
 

"Apollo Thunderbolt Windows Compatibility

 About UAD Thunderbolt Compatibility with Windows 10 Systems

• UAD v9.1 introduces Windows 10 PC mixed multi-unit compatibility with all Thunderbolt-equipped Apollo and UAD-2 products (Apollo 8, Apollo 8p, Apollo 16 MkII, Apollo Twin Thunderbolt, Apollo Twin MkII, UAD-2 Satellite Thunderbolt, and first-generation silver Apollo/Apollo 16 models equipped with a Thunderbolt Option Card).
• Apollo Thunderbolt models can be combined with UAD-2 PCIe cards and UAD-2 Satellite (Thunderbolt, FireWire, and USB models). For details, see this article.
• Both the original Thunderbolt 1 Option Card and the newer Thunderbolt 2 Option Card for Apollo are compatible.
• Apollo Thunderbolt cannot be combined with Apollo FireWire or Apollo Twin USB (multiple Apollo connection types are incompatible).

 
UAD Thunderbolt Compatibility Requirements

• A Windows 10 PC computer featuring built-in Thunderbolt 3 via USB-C is required.
• Windows 10 Anniversary Update 64-bit edition (version 1607 or higher) is required. Earlier versions of Windows are not tested or supported.
• A qualified Thunderbolt 3 to Thunderbolt adapter (not included) is required to connect Universal Audio Thunderbolt products to the USB-C port on the computer.
• Apollo Thunderbolt audio drivers for Windows are 64 bit only. 32 bit DAW applications are not compatible. 
• PCIe to Thunderbolt adapters, Thunderbolt to FireWire adapters, and Thunderbolt hubs are not tested or supported and may cause unexpected behavior.
• Connections to Thunderbolt 1 or Thunderbolt 2 computer ports are not tested or supported.
• Using Apple's Boot Camp to run Windows on Mac computers with Apollo or UAD-2 devices is not tested or supported.
• For general UAD system requirements, see this article."

I wouldn't make any big investment right now. I read yesterday that the people that developed TB3 and own the rights will be dropping the license fee next year and open it up to the market. They want some saturation in the I/O market and figure making it royalty free will encourage manufacturers to adopt it for computer design and make it more popular for 3rd party developers. This could change a lot in the PC world.

Thank you for the good information. By the time I read this thread, I called to Antelope and to my disappointment, they told me that if I want to use their new goliath. $7000 interface, I would have to use it with USB3. They claim that it works as good as Thunderbolt. What you think about this option?
 
This makes me wonder:
"PCIe to Thunderbolt adapters, Thunderbolt to FireWire adapters, and Thunderbolt hubs are not tested or supported and may cause unexpected behavior."
 
My motherboard, Rog Maximus Hero Z270 has USB-C port and connector for Thunderbolt 3. It would need a PCIEX4 card to use Thunderbolt 3, and I still not sure how it connects to USB-C- does it mean that the USB-C will be taken (in use)? So what do they mean by PCIe to Thunderbolt adapter? My motherboard has port but not a card, so is this card considered to be PCIe adopter or not?
 
The reason I wanted to go with Antelope is because I am a keyboardist and I have many keyboards- currently all my 24 tracks on Presonus FireWire mixer are taken. I need new interface to connect all my keyboards in stereo. I am not sure if I can trust UAD Apollo 16 and Apollo 8 or 8p connected together to work flawlessly as one. Or would it?
 
I also noted on AUD site it said- Apple adopter is not working, to find something else.

vladasyn
Thank you for the good information. By the time I read this thread, I called to Antelope and to my disappointment, they told me that if I want to use their new goliath. $7000 interface, I would have to use it with USB3. They claim that it works as good as Thunderbolt. What you think about this option?
 
This makes me wonder:
"PCIe to Thunderbolt adapters, Thunderbolt to FireWire adapters, and Thunderbolt hubs are not tested or supported and may cause unexpected behavior."
 
My motherboard, Rog Maximus Hero Z270 has USB-C port and connector for Thunderbolt 3. It would need a PCIEX4 card to use Thunderbolt 3, and I still not sure how it connects to USB-C- does it mean that the USB-C will be taken (in use)? So what do they mean by PCIe to Thunderbolt adapter? My motherboard has port but not a card, so is this card considered to be PCIe adopter or not?
 
The reason I wanted to go with Antelope is because I am a keyboardist and I have many keyboards- currently all my 24 tracks on Presonus FireWire mixer are taken. I need new interface to connect all my keyboards in stereo. I am not sure if I can trust UAD Apollo 16 and Apollo 8 or 8p connected together to work flawlessly as one. Or would it?
 
I also noted on AUD site it said- Apple adopter is not working, to find something else.

The best USB-2 audio interfaces are pretty close in performance to Thunderbolt-2 audio interfaces.
ie:  The RME Fireface UFX offers 4.3ms total round-trip latency at a 48-sample ASIO buffer size/44.1k.
The UA Apollo yields ~4.4ms total round-trip latency at a 32-sample ASIO buffer size.
 
USB-3 has plenty of bandwidth... 
Thus far, we've yet to see any USB-3 audio interfaces that best the low-latency performance of the best USB-2 units.
If Antelope delivers round-trip latency (and rock-solid performance) equal to the RME Fireface UFX, I have no doubt you'd be happy with the Goliath.
 
Asus chose to make Thunderbolt-3 an AIC (add-in-card) option for their motherboards.
Gigabyte offers Thunderbolt-3 directly on select motherboards.
I prefer the later... (but it doesn't affect performance)
 
Regarding the disclaimers:
I'd tested the Apple Thunderbolt-3 (USB-C) to Thunderbolt-2 adapter with several machines (2017 MacBook Pro, our Platinum Laptop, our Platinum Studio DAW).
Using a new UA Apollo, the Apple adapter worked in every scenario.
 
The UA Apollo series (connected via Thunderbolt) doesn't break new ground as far as lower round-trip latency, but the units work well.
The specs UA publishes are real.
I measured the noise-floor of the Apollo Twin Duo mkII... and the average noise floor was below -116dB.
 
A single Goliath vs. a pair of Apollos would be a tough decision.
You'd have about the same round-trip latency... and equally great fidelity.
Both offer DSP processing.
 
If looking at Thunderbolt based audio interfaces (running under Windows), make sure to know all the fine details.