You’d be forgiven for not noticing, but the top audio interfaces are one of the things that have been steadily getting better. That is, the handful of makers really focused on service musicians (and other audio and audiovisual applications) have improved interface quality, added a lot of features and connectivity, and improved driver performance.

MOTU is one of those makers on a short list that I hear good experiences with. But this fall when a press release crossed my desk saying they had more low latency performance, I wanted a bit more detail than the marketing language was offering. So I spoke to MOTU’s Jim Cooper to clarify a bit.

I know a lot of MOTU boxes are out there in the wild among our CDM readers, so I’d love to hear from those of you using them. (And I don’t want to just favor one vendor – I’d be happy to repeat this conversation with others, as these are the sort of chats I get to have with manufacturers, and it’s nice to be able to share them.)

TL/DR version: MOTU will give you lower round-trip latency on their latest boxes.

Also, some quick notes about what makes the UltraLite mk4 nice:

  • iOS, Linux. It does now do USB class compliant operation, so you can use it with iOS (or even Linux, in fact, even though MOTU don’t mention that).
  • Browser mixing. You can access a 48-channel mixer in your Web browser, meaning this does double duty as a mixer – and your computer becomes the interface.
  • Any input, any output. You can route signals in a customizable router, so any input can go to any output.
  • Quality! MOTU has put in what they say are “super high quality” converters; certainly, my research says you should have some good results

CDM: Can you go into some detail on the new low latency drivers for the UltraLite?

Sure! Our new low-latency drivers were years in development. These drivers (and the firmware in the hardware, too) are still actively tweeked and optimized, and we regularly release driver updates to further improve performance.

Which hardware is supported? I know MOTU has an integrated driver model, so that means you should see these benefits across the line?

The low latency drivers for the UltraLite-mk4 are for all audio interfaces in our new generation “Pro Audio” family. This covers the latest releases of UltraLite-mk4, the new 624 and 8A interfaces we announced last week, and all MOTU AVB/TSN capable hardware (UltraLite AVB, 1248, 16A, 8M etc.)

What did you do from a technical standpoint to make this work?

The short answer is…we started from scratch, spent a lot of time optimizing, looking at profilers, and optimizing some more. We have learned a lot from our 20 years of writing audio drivers and making audio interfaces. Starting from scratch meant that we could fully capitalize on those lessons learned. At the same time, operating systems have improved along with computer hardware. We can now count on machines having multiple cores and supporting Intel-intrinsic (SSE) operations, which helps a lot.

Okay, this is the one I’m most keen to know: how does performance compare on Windows versus macOS?

It depends on the machine and the software being used. Let’s assume most people have a decent, healthy computer and that we’re talking about USB.

For latency performance, we expect both platforms to perform well. Both should be able to do under 3 ms patch-thru or better. That’s like having your head about three feet further from an audio source.

For CPU performance, it’s mostly negligible on both platforms. The lower your buffer size, the more CPU we use, which has always been the case. In windows this is generally more true, so there will be a minor difference between platforms.

We want to mention that when connected via Thunderbolt, performance is a little better (for both Mac and Windows). Thunderbolt is also slightly more efficient with regard to CPU usage. But the main point is, with these new drivers, USB holds up remarkably well in comparison to Thunderbolt, given common industry perceptions.

Yeah, I’m currently spec’ing out PCs with Thunderbolt on. There have been some under-the-hood improvements I know to Windows audio lately. Any you would comment on, or that have implications for your projects?

Which improvements are you referring to? Since Vista they’ve had the MMCSS API, which gives DAWs a way to prioritize audio threads over most of the system, which really helps. That helps ASIO drivers quite a bit, too. Kernel drivers still have the limitations of poor timer accuracy and DPC scheduling, which make it more difficult to deliver audio buffers. But we have found ways to address those issues and deliver extremely solid performance.

Ed.: Well, we’re a bit behind, honestly, in tracking Windows changes. I hope to remedy that soon, though if you found Vista annoying and PC hardware options lacking then, some of the changes we reported on long ago made to Vista are now also in an OS that’s friendlier and more mature, and I think PC hardware has improved, too. I know there have been some other efforts on Windows audio that we need to keep up to date. And meanwhile on the Mac side, Sierra has fixed some things, too.

What should users of the UltraLite mk4 expect in real world usage?

A generational improvement in both the driver performance and the overall features and performance of the hardware. On today’s absolute fastest computers, we can achieve full, round-trip monitoring with RTL as low as 1.6 ms with a 32 sample buffer setting at 96 kHz. If you’re running a bunch of effects and tracks, then it’s probably a good idea to bump that up a bit. But even on a good machine (like what most of us have), you can easily achieve 3-4 ms RTL under most practical situations these days.

Thanks, Jim.


Okay, so you can add low latency features to the other stuff that’s nice on the UltraLite.

Meanwhile, MOTU’s 624 and 8A are shipping now. Interestingly, they include both USB3 and Thunderbolt. So if you need a mobile interface to swap between machines and not all of them have Thunderbolt, especially on Windows, you’ve got options. I would note that Thunderbolt is spreading fast on the PC, though.

The big deal with the 624 and 8A is that you get 32-34 channels of audio I/O, the ESS Sabre32 DACs with 132 dB dynamic range, and networked capabilities via AVB. I’m guessing AVB isn’t so relevant to most CDM readers, but for those of you needing to combine audio across computers and interfaces, it’s hugely powerful.

And like the other recent interfaces including the UltraLite, you get standalone mixing functionality you can access via any Web browser (even on mobile) on a WiFi network.

There’s also a suite of analysis tools with FFT, oscilloscopes, and visual analyzers.

The AVB stuff on the flagship offerings were nice, but I suspect these could be even bigger – well under a grand, and with I/O that fits a lot of needs.


  • Nice looking little box!

  • squirrel squirrel squirrel

    Kind of strange pricing structure with the 624 and 8A both being over $200 more expensive than the Ultralite-mk4. As far as I can tell, they both lose MIDI, the 8A loses mic pre’s, and all they gain is extra computer I/O in the form of Thunderbolt, USB3, and Ethernet. Am I missing something?

    • That’s why I said – I figured it’s not so much for the CDM audience (or me, for that matter). It’s really for people who need AVB networking, and they’re a different crowd — and a crowd that probably doesn’t need MIDI or mic pre’s.

      May sound like the value proposition doesn’t make sense, but on the other hand for this particular audience, they’d see that same proposition differently.

      If someone is using that functionality, do chime in. But the UltraLite I think is competitive … I’m strongly considering it for my next multichannel box, for sure.

      • wndfrm

        AVB is an attractive ‘unifying’ connective format.. allowing for massive channel i/o and expansion, remote control..etc..

        it can be platform agnostic as well.. really depends on hardware implementation i think? however there are competing ethernet-based standards, so again it’s another standardization game.. i was considering going that route, but now it looks like the industry *might* swing towards the MBP-endorsed USB C connector with fast TB iterations.

        although.. standards like AVB/dante/etc.. seem to be more ‘open’ and allow for working with a greater range of hardware.. for instance i could load the dante front end on my MBP and then use a 32 channel stagebox as my I/O .. or 18 of them..

        but yeah.. for home studio? pretty niche, and you certainly pay for that capability, not the best investment for someone wanting sweet sounding preamps.


        • Kingmetal

          I’m more confused about the 624 vs the Ultralite AVB, which I have. It seems like you lose some I/O, including MIDI for Thunderbolt and USB3.0. Those new VUs look cool though.

          I have had the exact opposite experience as everyone else posting with MOTU gear. I still have my first 828MKII that I started out on and besides a burnt out LCD backlight it still works and I’ve used it as a stand alone DAC for various weird projects. I’ve never had major problems with MOTH drivers, save for a little weirdness when slaving an 828MKII and a first gen Traveler (which I still have and use) over FireWire on a slightly sketchy PC I built running Windows 7, which eventually stabilized with a driver update. I’ve had excellent support from MOTU over the years. I switched to Focusrite for a brief spell in 6 years ago or so and found the drivers to of the same quality, except my Liquid Mix 16 which had horrible drivers.

          My Ultralite AVB is a joy to use. It works well on my work rMBP directly over AVB, my shitty $200 Windows 10 laptop over USB and works fantastically on my iPhone. Where MOTU shines is flexibility and the mixing and routing capabilities are what I really like about these interfaces and what keep them in my rack for years and years. I’m using my Traveler as an analog expansion unit via ADAT at the moment, for example.

          Anyway, I’m sorry to hear other folks had bad experiences with MOTU drivers. I can’t account for this, but certainly believe the horror stories. Just wanted to show my support and recommend you give the Ultralite a chance if you’re interested – maybe buy from a place with a return policy!

          • Kingmetal

            Well, posting from my phone was a bad idea. Probably not doing much good making my point with iPhone grammar and spelling. Sorry all, got too excited and should’ve waited until I was on a bigger screen.

          • wndfrm

            yes, as mentioned up top i have many friends with ultralites.. it’s a fantastic form factor. i’m glad your experience with these devices is also positive

      • DPrty

        Don’t do it. I am a computer repair tech with years of know-how. I have been through the Motu drivers on five different interfaces of theirs and it was all bad. Also they were setup on many different computers and many different configurations. This is on the Windows side of things. I have purged these device’s and am happy to report that after years of dealing with this companies products, I now have multiple machines running RME and Mackie interfaces with zero issues. I have tried multiple generations and types of Motu’s. It is all bad.

  • Paolo

    they sport a super converter

  • wndfrm

    when i bought my rme device, about 8 years agao.. almost 9.. MOTU was fraught with driver issues and complaints.. this drove me towards companies that were more pro-active in this regard, ending up with RME due in no small part to their very engaged customer service forums and very fast turn around time with posted issues.. also their drivers were updated very frequently..

    hoping that this is no longer an anomaly in the industry, and that MOTU have learned from that tie period.. their products have great value for the money, and the AVB implementation is quite attractive.. they are great options for anyone not needing to invest in high end preamps/convertors.

    anyone have current experience with MOTU’s customer service?

  • Robin Parmar

    I wonder if they are yet a shade on RME? Somehow I doubt it.

  • Dubby Labby

    They were pretty side to side with RME but bad driver support make them a “want but can’t” brand nowadays. I have more trust in Focusrite or even revamped Behringer with Midas preamps.

    MOTU is history IMO.

  • Tracy Evans

    A decade or so back, I vowed to never again buy a “non-USB-compliant” audio interface device. This was after custom driver support vanished on one of my favorite gadgets. Though no action of my own, other than keeping my system current, my fav device no longer functioned. This discipline served me well for the next few years and a few iterations of hardware.

    My question is: is this no longer the best strategy. Must I now go back to relying on custom drivers and resign myself to a device with a lifespan limited to the whims (financial viability) of the manufacturers constant support of device driver upgrades?

  • Kyle Sherrod

    My 1248 has been awesome and flawless on Mac, over USB as this system lacks thunderbolt. Never had a problem with it, and was a drastic improvement over my previous interface across the board.

  • chaircrusher

    The dude actually said close to nothing about how they achieved lower latency, and their ‘long experience in driver development’ — well their drivers on the Windows side were terrible years ago, and the comments on this post don’t really inspire me.

  • John Kennedy

    i’ve been using a MOTU firewire Ultralite on macs with no issues for over 10 years, on a 2010 mac pro and on at least 3 different macbook pros over this time. i just bought a used late 2013 macbook pro so now i have to use a thunderbolt to firewire adapter. i thought i was having an issue (no sound output) and contacted their customer support. the next day, i got probably the most thorough and helpful reply i’ve ever gotten from any customer service rep, with a couple of potential multi-step solutions. everything clear and concise and EVERY question i raised in my email to them was answered. probably i just got lucky with “the right” service rep but i was really impressed. as it turned out, i realized i had just forgotten to switch back to the standard Mix routing preset after a show i’d done a couple of weeks previous. There was no issue, it works just fine & i’m pretty damned happy that i can still use this 10+ year old interface. What don’t i like i about it? I hate the little knobs, they’re too close together & it makes it annoyingly clumsy to make adjustments. if they’d used those knobs with the cutaway wedges so you have a little flat surface to grasp, it would’ve been great. in practice, those knobs are just used for setting things up (& you can make all the same adjustments / mix setups in software). the actual volume & headphone volume knobs and mic pre gain controls are all easy to manipulate.

    My impression was always that MOTU were mac-centric. it seems Windows users have had less success. it’s been absolutely money well-spent for me. i’m sure i’d be quite happy with an RME but after 10 years of use/ownership i have no reason to switch. (all the built-in DSP in their recent boxes will be a nice bonus when i do eventually step up)

  • Peter Brinkmann

    My understanding is that MOTU has historically been a Mac shop, with Windows support grafted on much later. I’m guessing that the split between happy and unhappy users we’re seeing here agrees exactly with the Mac/Windows split.

    I didn’t consider MOTU for the longest time because their interfaces weren’t class compliant. That changed with the introduction of the AVB line, and I’m very happy with the Ultralite AVB I bought last summer. I am using their proprietary driver, though, because it promises lower latency; no problems so far, although it does seem a bit glitch prone when I choose a buffer size below 128 at 48kHz in Ableton Live, so I’m not quite getting the sub-3ms RTL mentioned above.

    Personally, I totally see the appeal of the 624 — great converters, Thunderbolt for low latency on Macs, plus class-compliant USB for Linux/Android/iOS. I believe Thunderbolt licensing fees account for some of the cost. If I didn’t already have the Ultralite AVB, I would be seriously tempted.

    • Dubby Labby

      Agreed but even before the usb/fw too much 828 madness they had problems with lcds and burn preamps. Since liquidmix Focusrite had gain more trust at the same time MOTU has lost it.

    • Elekb

      I agree. I can’t speak for drivers pre-2010, but I’ve been using a MOTU Ultralite Hybrid for 5 years, and there were serious usability issues on Windows – getting the audio driver to actually work on Windows 7 was very counter-intuitive, and performance was subpar compared to OSX.

      On macOS, on the other hand I had no major issues before 2013 – I say before 2013 because that’s when I updated to a new machine and was forced to use a Thunderbolt adapter – before this, no issues at all. With Thunderbolt: instability, glitches, Ultralite switching off when USB devices were connected, the works. Also the Thunderbolt port is the least professional thing I’ve ever seen. Just a light touch on the cable, and the TB thingy comes off. Bang, no audio. I actually had this happen a couple of times during gigs, very embarrassing.

      Driver-wise, yeah, in my experience MOTU works great with OS and… not so well on Windows. Considering I use both OSes and will probably be switching to Windows-only in the near future, I think I’ll be moving towards Focusrite, but, if you’re sticking with macOS, and you manage not to touch the Thunderbolt cable while you’re playing, MOTU is a good choice, and these new drivers will probably up their game.

  • 3 ms is extremely low. Would love to use that for guitar. Someone should do some extreme testing.

    • Freeks

      3ms needs 32k buffer and 96khz samplerate. Both are something u probably don’t use. Even a fast computer can’t do 32k buffer in normal session. And who use 96khz?

      • Agreed. I won’t use 96khz indeed. And probably anything lower than 8 ms on guitar feels like as direct as line input. Even lower than a real amp would give you through a mic-ed setup. I am already able to record like this using a Focusrite 1st Generation Scarlett 2i4.

  • Peter SydĂ©n

    The mixer is controllable with OSC. I control the mixer from Live which is quite convenient.

    • n_donmoyer

      whoa! is there a guide or walk-through to implementing this? i can’t seem to find much on google using ableton specifically

      • Eric

        I’m not sure exactly how he achieved this setup, but my best advice would be to start with OSCulator. I believe you can turn live’s faders into OSC outputs which can then be routed over Ethernet to the MOTU listening port! I myself will be trying this in the coming weeks

  • tomtakestooth

    I bought a second hand MOTU Ultralite MK3 Hybird as I wanted some more outputs than my Focusrite Scarlett 8i6 could provide. It’s pretty much unusable on my Lenovo Thinkad T430. I can’t get it to perform at decent latency and having the CueMix software open at the same time as running audio out of it, caused lots of glitching even at really high latency.

    Really annoying, as it seems like such a great interface in a small form factor.

    • TJ

      Were you using this via FireWire or USB? On a USB 3 or a USB 2 port? On Windows 7 or Windows 10? And which DAW/version?

      • tomtakestooth

        Windows 7, USB, plugged into a USB 2.0 port.
        Initially I had it plugged into a USB 3 port but that caused all kinds of other problems.

        • tomtakestooth

          Oh and this happens with bidule, reaper, reaktor in standalone mode… anything I use really

          • TJ

            Yeah, I’ve had that issue with USB 3, which is why I mentioned that. But, thanks. Also, was your wireless turned on or off? I’m just researching the Ultralite mk 4, which is why I ask.

          • tomtakestooth

            Disabling wifi, Ethernet, Bluetooth, webcam etc doesn’t seem to make a difference. Also tried windows 10 and have had the same issue on 3 laptops, Lenovo T430, x230 and T430s…

            Would love to know if anyone is getting a decent performance from one of these on USB and windows. Really wish I could get it working but think I’ll have to sell it and get something else.

          • Stefano

            See my report above. with my Ultralite AVB I cannot get robust or decent performance on 3 laptops that I tested. I’m going to sell it for a RME.

  • Ja

    I have 2 828mk2 firewire interfaces. 1st one I bought in 2005 or 2006 because it seemed to be best in terms of value. It broke down in a year – some sort of software or bios error. It took about 3 months to get a fixed unit back. They probably changed something inside. Since then I have had couple of problems- the LCD backlight burned out, took about 15 minutes to fix it myself and one output doesn’t work – haven’t checked inside, perhaps it’s just a soldering issue.
    I bought a 2nd unit last year because I needed extra outputs for one project that I was working on.
    In terms of sound quality they are probably not very good – tend to color sound, but at least the lower end sounds nice and all my analog gear sounds nice through it.
    Not sure if I would buy motu again, but at the moment there is no reason why not to. If they could add midi controlled mixer to their audio interfaces which wouldn’t require computer controlling cuemix, then I wouldn’t doubt!

  • partofthepuzzle

    Obviously, with Windows you have huge range of hardware to choose from and finding the right hardware for audio applications is critical. From my own experience, I highly recommend the high end ASUS laptops. I use a UV51 15 inch Zenbook and it has been flawless for production (Ableton Live) and DJing (Ableton Live and Traktor) for 3 years. It’s light and thin and has very high build quality. It’s every bit the equivalent of a high end Mac Book Pro for about 1/2 the price.

    RE: Windows. The ASUS came with Win 8 installed and I was planning to reformat and install Win 7, however I decided to hold off and give Win 8 a try. OF course, Win 8 had the major flaw of the “Metro” paneled interface and Start menu, etc. To address this, I installed Start 8, a $5 Start Menu replacement. There are also free equivalents like Class Shell but I found Start 8 to be the best and worth $5. Start 8 provided the familiar and preferred Win 7 Start menu and most important, it enabled me to completely avoid the Metro side of Win 8: I NEVER even see it – it effectively doesn’t exist in my daily use.

    The advantage of Win 8:

    – MUCH faster and more stable that Win 7 (cold boots in 3 sec)
    – It doesn’t have the controversial privacy concerns of the extensive user telemetry in Win 10
    – Better control over Updates
    – No ads or other intrusive behaviors

    All of the above is just my own anecdotal experience but I thought some folks might find it helpful.

  • Buzap

    On Mac, I’ve been having wonderful experience with Motu Ultralite mk3 Hybrid for years.
    That’s why I bought one for a Windows PC at work. Big mistake. With glitches and noises, Motu is completely unuseable on PC. Tons of forum comments were also not encouraging. Couldn’t return it any longer and had to sell it off.
    On PC, now I run a Focusrite Scarlett (1st gen) with absolutely robust performance (you notice difference to Ultralite in preamps/headroom,though).

  • Stefano

    I own an Ultralite AVB since Dec 2015 and I’ve been continuously reporting glitching issues to MOTU, under Windows 7 and 10.
    I recently tested 3 different laptops, all optimized for audio, ranging from i5 4200u to a i7 4960HQ. Even on my most powerful computer I cannot go below about 7ms round trip latency @ 48kHz (128 samples buffer and 32 samples host safety offset) with Ableton Live 9 and a single moderately heavy VSTi. Even in that case I get occasional dropouts. My other machines, including a new i7-7500u are hardly working with the Ultralite: I couldn’t find a single setting which avoids dropouts, including biggest buffers (1024 samples buffer and 256 samples safety offset). Also I get a lot of glitches when using the webUI and with basic graphical tasks like moving or scrolling a window.
    What’s weird is that increasing the safety offset buffer doesn’t help at all. Actually, I get worse results for anything different from 32 samples safety buffer.
    For comparison, I tested a RME UCX and a Focusrite Scarlett 2i2 mk2 and they both work just fine, The RME especially works great with 64 samples buffer (round-trip latency 4,2 ms) even under heavy load.
    After all this time testing and reporting to MOTU, I decided to sell my Ultralite and buy a RME.

  • Samolo

    I would love to have some more reviews from you guyz about the interface. It’s been 5 months and i’m still in between buying it because of all the bad reviews from people on windows