Elk Live

With their clever audio networking technology, Elk Audio aim to make low‑latency, long‑distance collaboration a reality.

It’s 2020 and the first lockdown has just begun. My wife Anne and I sing in a three‑part close‑harmony group called Eagle Alley, with our friend Rob who lives 12 or so miles away. Our group cannot of course meet to practise, but really want to. We’ve experimented with Zoom and learned for the first time the awful impact of the word ‘latency’. After a lot of searching we discover an open‑source package called Jamulus, which has somehow managed to minimise latency sufficiently to permit us to sing together, and gratefully we resume rehearsing, but now over the Internet.

I was sufficiently impressed with Jamulus to write a feature about it for Sound On Sound (Setting Up & Using Jamulus, September 2020). Even though lockdowns are (we all hope) a thing of the past, Rob has recently moved rather further away, and so we’re still using Jamulus from time to time for rehearsals. Consequently, I’ve been keeping an interested eye on low‑latency audio software, and so was much intrigued when offered the chance to review the Elk Live Bridge, a hardware solution from Swedish company Elk Audio which is claimed to offer very high performance whilst remaining extremely easy to use. Elk Audio have devised their own version of Linux called Elk Audio OS, which is heavily optimised for low‑latency audio and which lies at the heart of the Elk Audio Bridge.

Well, that’s how this review started, but I have to tell you that halfway through, the review changed completely. Initially, I was looking at a very interesting, if expensive, hardware approach for low‑latency music‑making over the Internet. By the end, I was exploring a whole ecosystem of hardware and software alternatives dedicated to this end, which is temporarily free of charge in its software aspects (you still have to pay to buy the hardware). So: how to proceed? I will start with the hardware route, because that’s how I met it and the user experience is remarkably similar in both approaches.

The Elk Live Bridge has much in common with a typical audio interface. On the front panel are two XLR/jack combi inputs and two headphone outs, while the rear panel houses USB power and host ports, stereo line outputs, MIDI I/O on mini‑jacks, optical I/O ports, and an Ethernet port for connecting to your router.

Bridging The Gap

At first glance, and indeed at second or third glance, you might well mistake an Elk Live Bridge for a conventional audio interface. The solidly made and attractive metal case has two XLR/line combi inputs on the front plus two headphone sockets and, on the back (in order), USB power in, left and right line outs on quarter‑inch jack sockets, two mini‑jack sockets for MIDI I/O, two optical I/O sockets, an Ethernet socket, a USB host socket and finally a USB data socket. Then you might notice that apart from a small on/off button there are no physical controls at all, and no LED meters or indicators either (in fact there are some LEDs, but they’re well hidden underneath).

The package contains the Elk Bridge itself, along with a natty carrying bag for the unit, a short Ethernet cable and a PSU.That’s it: there’s no printed documentation of any kind. However, look carefully in the box and you’ll find this text printed on part of the packaging:

“No paper manual?! Nope. We hate paper cuts and want to make sure you get the latest and greatest. You can find everything else you need at www.elk.live.”

So off you go to the Elk Live website, where you will find the information you need to get started, the gist of which is this. Unlike a conventional audio interface, the main connection your Elk Bridge makes is not to a computer but to your router. This connection must be by Ethernet cable, as is normal with low‑latency products for the Internet — Wi‑Fi has too many latency problems of its own to be usable. The data USB port is not necessary for the use and control of the Bridge (although more about what it’s there for later). You don’t need to install driver or control software on a computer either: everything is done via the Elk Live website. The other significant requirement is a decently fast Internet connection. Elk Audio recommend a minimum 10Mbps up/down speed, and ping less than 10ms. They also suggest that all participants in an Elk Live session should be within a 1000km (620 mile) radius of each other in order to achieve good latency (that’s pretty good, actually).

Like & Subscribe?

Once you’ve plugged your Elk Bridge PSU into the mains, connected up your Ethernet cable to your router, plugged in a mic or an instrument and attached a pair of headphones, it’s time to set up an Elk Live account. This is where things are starting to change. Creating an Elk account is the first step in setting up a subscription, which is essential as you can’t join an Elk Live session without one. When I started this review, subscriptions cost £13 a month, so in our case, with three people, that potentially meant paying £49 each and every month to use the service. The big change is that, since the beginning of April 2023, subscriptions are free while the company ponder the best funding mechanism for the future. Much more about this below.

Note that for all web interactions, Elk Audio recommend the Chrome browser as that’s what they use in development, but I used Firefox throughout this review with no problems. Also bear in mind that although the Bridge is connected to your router and not your computer, you will still likely need to have your computer near the Bridge. This is because your mics and instruments run on the Bridge but the control software is a browser running on your computer. So, having set up your Bridge, your account and your subscription it’s time to go to the Elk Live web page...

Screen 1: The Elk Live browser‑based app’s splash screen, where you can find friends and invite them to your session.

Note how at the top left‑hand corner of Screen 1 it says ”Bridge status: All good to go!” If your Bridge is not connected or switched on it will say “Bridge not found”. All being well, the first thing you will want to do is contact your band colleagues, who will also have Elk Bridges and have set up Elk Live accounts. This process is called Add Friends. For this, you supply the email address of a person with a Bridge and Elk Live account who you want to play with. They will be notified through their Elk Live account and must accept before you can invite them (or they can invite you) to join in a session. So, having got acceptances from all the group, you can start a new session and invite them to join.

You can see three tabs across the top of the page: Backstage, Video and Mixer. Backstage is where you invite your friends to play — in Screen 1, Rob is the only one to have accepted so far. Video is where you can see the other participants in the session, Zoom‑style.

The Mixer is so called for obvious reasons, and as you can see in Screen 2, Rob has now joined us. On the left is where you set up your inputs: mic, line, guitar and so forth. There’s also an option for USB that I’ll talk about later. I’m using both mic inputs on the Bridge, one for my mic and the other for the third member of the group, my wife Anne.

Screen 2: The Mixer page, with input levels on the left and return faders on the right.

You remember the MIDI and Lightpipe I/O ports on the Bridge? Those don’t do anything yet, but Elk Audio have plans for them. In future versions of the software you will be able to send MIDI data to session participants and vice versa. The Lightpipe ports will support both S/PDIF and ADAT; the latter is particularly interesting, as that would give you up to an additional eight channels if you want them.

The gain you select in the Inputs section will affect the volume level you are heard at by your colleagues. The right‑hand panel, on the other hand, affects the volume you hear in your headphones. There is a fader for each participant, including yourself — if anyone is using more than one input there will be a fader for each — and you can set the relative levels of all the participants to give you the monitor mix that works for you; others are not affected by the settings here, as they have their own faders.

There are two headphone sockets on the Bridge, but only one works at a time, which is a slight shame since I and Anne both need headphones. However, that headphone output is more than adequate to support two sets of phones via a simple splitter cable, and so we were off.

The first time Rob and I tried Elk Live, we used mobile phones so we could talk to each other while we got things working. We made all the obvious mistakes like forgetting to switch on phantom power and not noticing that the master volume was down at zero, but once we’d got past those we were up and running in what was a remarkably straightforward and trouble‑free link‑up for nearly an hour until we decided to stop.

It was excellent; virtually free of the pops, clicks and bubbling mud that sometimes afflicted us with Jamulus, and latency was very low. We could sing in harmony together with confidence.

Live & Direct

And now the big question: what was the quality like? Well, it was excellent; virtually free of the pops, clicks and bubbling mud that sometimes afflicted us with Jamulus (though, in fairness, never enough to stop us singing), and latency was very low. We could sing in harmony together with confidence. We had video, though of course it was not sync’ed. There is an option to sync sound and video, but Elk Audio recommend you don’t use it for music because of the high overheads it has. There’s also a Zoom‑style chat facility, which we didn’t use much, though I can see it being pretty essential for anyone who’s not using a mic.

In Screen 3 you can see a big red X at the bottom. Clicking it brings the session to an abrupt halt, something we did accidentally on one occasion — an “Are you sure?” prompt might be useful here.

Screen 3: Elk Live incorporates Zoom‑style video and text chat.

It is possible to connect the Bridge to your computer via USB. This is in addition to the network link and does not replace it. If you do this, the Bridge appears as a class‑compliant two‑in/two‑out audio interface, which is still controlled from the web interface. In its current implementation it is very limited. For example, if you want to output sound via the Bridge, you have to set both of its inputs to USB, so you can’t use mics or instruments at the same time as USB input. But it does give you a way of recording what you can hear in your headphones. You need a DAW for this (it can be something as simple as Audacity) and you select the Bridge to be the stereo input to the DAW. You can then record the session as a stereo track.

That, at least, was the position up to the beginning of April. And then (flourish of trumpets please) everything changed. Elk Audio released a native software package they call Elk Live. This is a beta release, and currently runs only on macOS from version 11 onwards. It is standalone software and doesn’t require the Bridge hardware, although if there is a Bridge on the network, Elk Live will find it and use it. Otherwise it will locate the audio interface you are using and treat it as if it were a Bridge, ie. a simple two‑in/two‑out interface (this, I understand, is a temporary restriction and will be lifted in a future version). Simultaneously, Elk Audio made the subscription element free, at least for the time being.

My colleague Rob uses a Windows machine, and so cannot use the native app. This gave us the opportunity to see whether the app and the Bridge could communicate successfully across the Internet. On starting the native app I was asked to log in, then to choose my interface, and after that the experience was almost identical to the web version with the Bridge, and completely trouble‑free. The sound quality was as good, too.

One issue I encountered is that trying to run a DAW (Apple Logic Pro in my case) at the same time causes all sorts of confusion, and so for now you can’t record a session at the native end. This is apparently a known issue and the only one we hit during our use of it.

The Future

So what we have here right now is some very nice hardware and software enabling musicians to make music together across the Internet. But Elk Audio are not alone in this; there are alternatives already available, such as the open‑source system Jamulus I use regularly, and people like Zoom are beginning to take an interest (see box). But what I think makes Elk Audio particularly interesting is their plans for the future, given the firm platform they have built to start from. I had a long conversation with Björn Ehlers of the company, and here’s a summary of where Elk Audio hope to take this technology.

The current free subscriptions are, as I’ve said, temporary, but Björn says they will remain free for at least two months (this at the beginning of April) while the company decide what pricing model they want to adopt for the long term. It will definitely be a ‘freemium’ model, though Björn was very certain that the free tier will be capable of worthwhile use, ie. doing the basic thing of playing together over the net. The paid tier would have some of the more advanced features discussed below. The balance between free and paid is very much under discussion right now. They view the free period as a chance to learn more about how people want to use the system, and for more people to learn about Elk Live. That is welcome news, as at the beginning I was uneasy about the cost for everyone of forking out £13 a month each (and that on top of the £300 for the Bridge).

The native app is also getting a lot of work, of course, what with producing a Windows version and extending the functionality to match the Bridge and beyond, but what they’re also working on — and hope to have ready in a couple of months — is a VST plug‑in that can run inside a DAW and act as a link to the native app. Once this is available, you should be able to play tracks from your DAW into the Elk Live session, where they could be heard by all the participants. It should also be possible to record whatever comes out of the Elk Live session back into your DAW, giving the facility to overdub parts over the Internet. Future development beyond that would include the plug‑in being able to handle multi‑channel output from the native app so each participant’s output could be routed to a separate channel in the DAW. Elk Audio regard the VST as a priority and I can see how valuable this could be in many ways.

Longer‑term, they’re thinking of ways to synchronise video after the event using time stamps to support making videos for streaming and distribution. Further still, they’re thinking about online live event staging with an audience watching and listening to the session — not just for concerts, of course, but masterclasses and other educational uses.

Big players such as Zoom are also getting into the low‑latency act, and Björn welcomed this. The biggest challenge in making their proposition more widely known, he said, was simply convincing people that low‑latency Internet audio is even possible! His view is that this is an underdeveloped area of the Internet and that the more people are involved in developing low‑latency applications, the more it will be taken seriously, and the more opportunities there will be for companies like Elk Audio.

Now that the native app is out there and working well and being developed further, I had to ask Björn if there is still a future for the Bridge. As he says himself, you should get the same performance from the app as you do from the hardware. His reply was that, firstly, you can use the Bridge with devices such as iPads, whereas the native app needs a reasonably capable computer, and second, there are people who don’t want to get involved with audio interfaces and stuff but would rather just plug a box into their network and get on and play. But he did accept that the main focus in future would be the native app.

At the end, Björn said that the basic message he was trying to get across was that Elk Live is free to download and free to use, and so anyone interested can give it a try.