Adding or switching interface

[steve trusty]

I have a Tascam us2x2 interface I’ve had for years. Recently got the Tascam 4x4hr to use the loopback feature mainly for streaming/obs recording with cakewalk edrums.

Can I use both interfaces simultaneously for 6 inputs now and/or swap between the two? Would I need to run splitters from the outputs to the same speakers? 

If I do away with the 2x2 and use only the 4x4,  Will saved midi settings or any other major settings be affected in old/new projects??   Or is that a dumb question? ?

I should mention I also have a motu 4x4 midi usb interface running as well.  I use midi on the 2x2 for my edrums. 

Win 10 16g 

thanks ahead of time! 

[scook]

Different interface same discussion

The bottom line is if interfaces can be aggregated, the hardware documentation will cover how to do it.

It takes a specially designed ASIO driver (ideally although other driver modes may work) and a way to sync the devices to the same clock.

This is something hardware vendors who support the feature document.

Any audio or MIDI interface changes will likely require adjusting projects to suit the new hardware.

[Terry Kelley]

Hi Mr. Cook.

Your point is probably the best way to infer what can and can't be done. I could never find someone that tried it and said it didn't work but only, "it probably won't work." Sounds like SteveT is the first to confirm it with real world results that I've seen.

Presonus has a long drawn out paper on how the clocks work and even gets close to saying that "reclocking" would allow multiple interfaces. But when they get to the meat of the subject their answer is get interfaces with external clock inputs and lots of BNC cables and tees or get an interface with more inputs and outputs.

After playing with multiple interfaces (and Mr. McLeod said it best) you can get close but not perfectly in sync with reclocking (meaning let the interface handle it.) Apparently Macs will allow some interfaces to be merged but staying in zero phase-sync is still an issue according to users. I did some phase measurements with several borrow interfaces using WASAPI Exclusive and I could never get them within more than a couple of milliseconds of delay. Even two identical interfaces drifted or had a measurable (and audible) delay. It would work but I couldn't expect to get a solid mono localized image between two interfaces (like front and rear left.) Ain't gonna happen unless it's pure luck and it's unlikely they will stay that way.

So I conceded (through testing), that if it works it's still not locked and stable. Get a multichannel interface or interfaces with external clock inputs.

And the ASIO driver for the Behringer UCA-222 just picked one interface, not both.  I never got to test two Presonus with ASIO.  You would think that given the bandwidth of even USB 2.0 you could send sync pulses or sync clock to multiple interfaces but it appears that's not in the cards.

Edited July 22, 2021 by Terry Kelley

[scook]

Yeah, the ability to run multiple devices is not something manufacturers keep secret.

If their devices are designed to run together, it will be documented and included in their marketing material.

The opposite is not true. IOW, don't expect manufacturers to go out of their way to document their devices are not designed to run together or see that as a bullet point in their marking material.