USB 2 interface 2014

Yes, I’ve searched. I’ve looked at the alsa compatibility matrix and all over the interwebs.

I’d like to purchase a USB 2 interface for use with ardour3 on Linux. It really needs to have at least 4 mic preamps on board with phantom power. I’d also like it to be portable (I record a lot of piano, I don’t own a piano or a decent performance space so I travel a lot to use other people’s, universities, churches etc.). All the suitable looking interfaces I’ve found mentioned on the various forums are ancient and can’t easily be purchased new any more.

Does anyone have any experience with a device that would suit my needs?

I have a Focusrite Scarlett 18i20 and for recording and playback purposes it works perfectly in my experience (provided your Linux kernel version is recent enough to support it). It has 8 preamps (all with phantom power but switched in banks of 4), which I think sound great, something that many reviews I have read agree with.

The only thing is that the official Mixcontrol program isn’t available for Linux and there is no way to configure the interface’s routing matrix from Linux (I have seen some 3rd party efforts at mixing programs but I don’t believe that any are finished). However, this is mainly useful for live monitoring, and if you have Windows/Mac you can use Mixcontrol from there and save the configuration to the interface before using it on Linux.

If you don’t need as many as 8 preamps, I think the other interfaces in the Scarlett range are basically identical but with different numbers of inputs and outputs.

Thanks, I’ll check them out.

No experience with these… but they look good and generally get good reviews.

Presonus AudioBOX 1818VSL…

You won’t get the onboard DSP… as with pretty much every device under linux.


I have a 1818VSL, they generally work well but can be a bit flaky and randomly stop streaming audio occasionally, and in my experience they are VERY picky about USB chipsets on the host machine, for example with my laptop it works decently well, my son has a laptop of similar age and with the same OS/Kernel the VSL is too flaky to even use, however a Scarlett 2i2 is bulletproof on the same machine… go figure…? Another observation about many USB-2 devices is that their latency performance is quite mediocre without a full RT preempt kernel and lastly many USB-3 chipsets on new computers perform very badly for audio when running USB-2 Audio devices, this is known and probably will take a while to get reliably fixed in future kernels…

Buyer beware, and try before you buy if possible…

We have an 1818VSL at our rehearsal studio. It is usually used with Ableton on windows. I tried it with my laptop, it worked one day when I was testing. When I came to try and use it for a project, I just couldn’t get it to perform stably. I had a group of angry looking musicians staring at me so I resorted to using Ableton on our windows machine.

I think it had something to do with USB3, I think I have one port on my laptop that uses a USB2 chipset, the othe uses a USB3 chipset. I may try again, just to see if that was the issue, but I fancy something that is always going to be reliable. I only get limited time in the various venues I can borrow, so I can’t really afford much messing on location.

Another strange thing about the 1818VSL is that the preamps all seem to require different gain settings to achieve the same level with the same input signal. It’s only about 18 months old, so I don’t hold out much hope for its longevity.

About the focusrite scarlett series…

Am I right in thinking that the monitoring routing is carried out using an onboard digital mixer that is inaccessible on linux at the moment? I’m wondering what I’ll miss out on. If I set up a monitor mix using ardour, but have the intruments being tracked use the zero latency monitor path, would I lose the ability to set their monitoring levels without resorting to a utility used from windows? Would I be able to use WINE or virtualbox to access the MixControl while Jack is still running (not ideal, but is it even possible)?

What kind of latency can I expect if I’m monitoring in software using ardour. I use debian with a realtime kernel, but only really manage approx 17ms before I get XRUNS with my Alesis I/O2, this makes it essential to use the direct monitoring facility. I’m willing to put in some work to achieve better latency if I should expect better.

Also, the scarlett ADAT input. On the smaller unit (18i8), there is no wordclock input/output, but there is an ADAT input. I assume the 18i8 would use the ADAT input for synch, but isn’t this likely to increase the jitter possibly to a noticebly unnaceptable amount. I really fancy the 18i8 over the 18i20 mainly because I like to carry the interface with me along with mics, stands, cables, headphones etc. The extra bulk may well be the straw that breaks my back. However if I’m missing out on upgradability when I’m in the studio, I might just put up with the bulk.

They are a huge amount of money that I don’t really have, so I want to be fairly sure that it is usable and flexible when I get it.


I hate to say it, USB-2 devices on Linux have made some headway… but… FireWire is still MUCH more stable generally speaking with out all the caveats like having a special kernel, not having USB-3 ports etc. etc. FireWire is not all roses either it’s biggest deficit is it’s impending obsolescence and it is picky about the host adaptor chipsets. but there are still better choices for pro-grade multi I/O hardware on FireWire although you may have to find them second hand. An unfortunate conundrum really…

Yup, I can find firewire interfaces no problem. I can’t find reasonably priced laptops with firewire :frowning: .

I think I’ll struggle along with USB for now. Maybe I’ll have a look at controlling the onboard mixer myself. It’s the kind of project I used to enjoy, but that was before life, family and music got in the way.

Well many open source projects are started by someone scratching their own itch, maybe its time to open up vim and start scratching :slight_smile:

The Zoom H6 is portable and has four preamps, in addition to the built-in mic. It works under linux according to this thread

It is sold as a portable recorder, but can also act as a audio interface with six channels input and two outputs.

That sounds interesting thanks Andreas. I’ll check that out. Do you have experience of using this with Linux?

The Steinberg UR44 has four mic preamps and is portable. It has a class compliant mode, so theoretically it should work on Linux, but I have no firsthand experience testing it. There is a switch on the back of the unit to select this mode if not using the supplied proprietary drivers for Windows or OSX (meant for iPad usage but could be useful for Linux systems as well). It is relatively new, so it may be a while before anyone reports on its functionality.

No, i have now personal experience, unfortunately. There is also the new Zoom H5 which works in a similar way, but has only two XLR connectors. It is quite a bit cheaper and if you are happy with the included X/Y mic, two extra inputs might be good enough. (i.e. it has four inputs and two outputs)

Thanks for all your suggestions. since I first asked, I’ve been offered a reasonably well paid project which will involve recording piano, strings, choir and other fun stuff. I will use the cash to get the big focusrite and some mics.

I’m still keeping a lookout for the other interfaces. There are a few people I know who are setting up recording systems, I might be able to talk them into being guinea pigs. I’d be really interested in what’s available.

Things like the Steinberg UR44 look interesting, but does class compliant mode mean the original USB audio class 1? Quite a lot of the “class compliant” USB2 stuff is only compatible with the early specification as far as I can tell. There are some new interfaces from Behringer that look really good, they are not available in the UK right now, but they seem remarkably good value for money.

The zoom stuff looks really also looks really interesting though. It would be perfect for live recordings of my band. e.g. the onboard stereo mic + an output from the FOH feed + a subgroup vocal mix could end up with quite a good live recording from a tiny unit. I’ll keep that in mind for the future.

I think I’ll try and borrow as many interfaces as I can. The ALSA compatibility matrix could do with a bit of an update and it should be fun testing!

@bdp: I have the Behringer UMC204 (2 in/4 out) and it works great at 44.1khz but anything above that it pops and clicks consistenly every 5-20 seconds. I have noticed that when I disable the input side through JACK the pops and clicks go away but 44.1khz is more than enough for what I do live. Using it live with Ardour3 as a sort of sequencer I have 1 guitar track, 1 bass track, 1 click (metronome) track, and 1 cue track that comes out of the same channel as the click and it all has worked flawlessly with no issues at all. That’s 3 sometimes 4 outs being used simultaneously depending on if I have 2 recorded guitar tracks and it’s been great. Been using it for about a 2 months now. They have the UMC404 4in/4out same as mine except 2 more inputs that looks pretty good too.


I take advantage of this post - maybe not necessary to open a new one for my question about audio interfaces.

I expect to get an :
Sound Devices USBPRE 2.

After reading on the Sound Devices website, that it’s usb compliant and work with Gnu/Linux - it’s on the website, and in the manual of the product, congratulations Sound Devices !
To be sure, i check on the audio interface section of the System Requirements page of Ardour ( ). Good the Sound Devices USBPRE2 is recommended.

« Sound Devices USB Pre 2 (in USB 1 mode) »

Why this «in USB 1 mode» ?! The USB 2 mode is not supported ?!
Someone can tell me more about this ? Best : Anyone here own this usb audio interface ?


ps : i use a Focusrite Scarlett 2i4 which work perfectly. USB 2 supported.

There are a few people that own and use this interface on the Linux Audio Mailing List, I would encourage you to post there for more hands on experience.


@bdp I hope the focusrite does what you need it to. Good luck! Let us know how it goes!

With regards to its internal mixer, you are correct. I have seen some patches for the alsa driver here ( but I don’t know how well they work and I think you still need a mixer program that can handle all the options of the internal mixer properly.

I have tried to run mixcontrol in wine, and while the program (and the USB drivers!?) install without error, the program doesn’t detect the interface when run. I guess it’s a driver issue. Not sure about windows in a VM. If it could get direct hardware access then I don’t see why it wouldn’t work because you would be able to install the drivers.

I honestly haven’t pushed the jack latency very hard because I just use the zero latency internal monitoring when recording. This works really well for me and I don’t mind booting windows for 5 minutes before a session to set the monitor mixes up.

Focusrite 2i4 as well as Native Instruments Komplete Audio 6 run basically out of the box here on KXStudio. Have to say that the NI KA6 seems to cause less problems though. Engine crashes more often with the Focusrite. Not sure at all if that’s because I failed getting optimal settings for the Focusrite and somehow hit the target a lot better with the NI interface. Just my observations.


I will take this post, as my question is about the same topic.

I was about to buy a behringer umc404 (4 inputs / 4 outputs, up to 96Khz/24 bits), but now it is not possible to find it, but it is available the umc404hd (same, but up to 192Khz). Sadly, I do not find any information about 404HD and linux, and I do not find anything about this device and linux. The only I found is this (in portuguese)

Does someboy has any experience with this?