On Wed, December 5, 2018 4:47 pm, liebrecht(a)grossmann-venter.com wrote: For monitoring while recording, hardware monitoring is often optimum The jackd server uses ALSA for interfacing to most audio devices, although it does have a way to directly use some Firewire devices. Really the question should be is there a driver for a particular Thunderbolt device you want to use. My understanding is that Thunderbolt is basically PCIe with some slight modifications to allow hot plugging cables, determining whether the peripheral needs PCIe or DisplayPort protocol, a few other things, but the important point being it does not define audio transport as for example USB audio class does, so even if one Thunderbolt interface is supported by ALSA, that does not mean that other Thunderbolt interfaces would be supported, you would still need a driver that takes care of register level access to the specific device you want to use. That question is not well formed. Thunderbolt is a data transport used in computers, not specifically an audio transport. AES50 and MADI are specifically an audio transports, and no computer has a direct AES50 or MADI connection. So again, the question is what particular audio device would you like to use, and then see if there is an ALSA driver available. The lowest latency would be PCIe connection from your processor to a device with analog converters on board. Many people have reported good results from RME devices over the years. If you happen to already have an analog converter you like with AES3 or MADI interface, RME has cards with those transports as well. But that is specifically just addressing the lowest latency way to get data from your processor to an analog audio connection. You did not explain what you are trying to achieve, so spending money on an interface that can run with low latency may not be the best way to achieve what you really want. Not to mention that there are many more system considerations than just interface transport in determining latency, you can spend quite a bit of time optimizing your system for low latency, but there are still quite a few things out of your control on a modern Intel based system (such as system management mode firmware that runs outside of the control of the kernel scheduler). So do you need low latency for monitoring while recording? Probably hardware monitoring is optimal (either with an interface that supports hardware monitoring, or by using an external analog mixer, preamp, etc. which supports monitoring features). For software synthesizers? Then system latency will probably dominate over audio interface, you will have plenty to work on before nearly any interface is the limiting factor. -- Chris Caudle