So the wait is over and Audiobus – an iconic app that, without making any noise of its own, is perhaps one of the most important music apps in iOS music technology’s relatively short history – has reached its third iteration.
If you are new to iOS-based music making, then you can be forgiven for perhaps not knowing quite what the fuss is about. However, in the days before Audio Units (AU) or Inter-App-Audio (IAA), Audiobus was the first practical solution passing audio data between your various iOS music apps in real-time. In the world of desktop music production, OSX and Windows have offered ‘plugin’ formats such as VST or AU for so long that users on those platforms simply take them for granted; if you buy a virtual instrument (or audio effect) to use on the desktop, it will come in at least one flavour of these well-established plugin formats (or, frankly, it won’t survive in such a competitive market). You can then load it up into your favourite DAW/sequencer for a pretty seamless workflow.
That level of virtual instrument/effect integration is still not (quite) with us yet under iOS. Audio Units is undoubtedly going to be ‘it’…. and is now certainly making much faster progress than when it first appeared some 18 months ago. But we are not quite ‘there’ yet; lots of favourite iOS music apps are not yet available in an AU format (and some may never be so) and the AU format itself is still in need of some refinements at the OS level (Apple’s job; fingers crossed for iOS11). So, technologies such as IAA and Audiobus, while perhaps less critical to some iOS musicians, are still very much relevant.
So, with v.3 now available, is Audiobus an iOS music utility app that ought to be on your ‘most wanted’ shopping list?
Something old, something new
I’ve done full reviews of the major v.1 and v.2 releases of Audiobus here on the blog in the past. Those new to the app might do well to look back at the Audiobus 2 review to appreciate where the app is coming from and what, up until now, has been its core function. However, in short, Audiobus 2 provided a way of accepting audio inputs (from an external audio device connected to your iOS hardware or a suitable app such as a synth, drum machine or guitar rig sim), passing that signal through further ‘effects’ apps, before sending that audio to an ‘output’ (again, either a physical audio output or to a further app such as a DAW/recorder). All those apps did have to be ‘Audiobus compatible’ though…. which is why ‘Audiobus support’ has become such a common feature of most iOS music apps.
Audiobus v.1 offered that functionality but, when v.2 appeared, it added the ability to run multiple sets of Input-Effect-Output slots. This allowed you to construct much more complex combinations of apps (providing, of course, your iOS hardware could keep up). And v.2 also added ‘State Saving’, allowing you to save the configuration of apps for later recall. This last feature required the various apps to include State Saving support and, it has to be said, it has never really offered the same level of ‘restore my entire project’ smoothness that your average desktop DAW/sequencer provides. It was certainly a useful step in that direction though.
All that core audio routing technology – and State Saving – are retained in Audiobus 3. I’ll not dig too deeply into that here, therefore, as you will either know it already (as an Audiobus 2 user) or can nip over to the Audiobus 2 review to read the details (no problem; the rest of us will wait here).
So what does Audiobus 3 bring that’s new? Well, there are perhaps three key things. First, Audiobus 3 how offers AU hosting. Any app that’s available in an AU format can be loaded into a suitable Input, Effect or Output slot within Audiobus and, yes, you can also have multiple instances of such AU apps (one of the advantages of the AU format) running within the same Audiobus project.
Second, as well as audio routing, Audiobus now offers a comprehensive system for MIDI routing. This is not a trivial feature as MIDI under iOS is still somewhat…. well…. unpredictable. Again, this is something that may become a non-issue when the AU plugin format becomes as ubiquitous on iOS as it is on the desktop, but for now at least, a central ‘MIDI hub’ is an attractive possibility. Audiobus 3 attempts to provide just that.
Third, Audiobus 3 now provides basic mixing features for all your audio input sources. This is, of course, very useful, especially when you are running multiple signal chains. Indeed, it is perhaps so useful that more than a few iOS musicians have wondered why it wasn’t a featured offered in Audiobus 2 at some stage. Well, it’s here now and will be instantly useful in both recording and live performance contexts.
In terms of more pragmatic matters, the app requires iOS10.2 or later, is universal, a 47MB download and is priced at UK£9.99/US$9.99. There are no IAPs to purchase; all features are included in the base price of the app. And if you don’t wish to move to the new version, Audiobus 2 is going to stay on the App Store as a separate product.
I think ‘new product’ – as opposed to ‘free update’ – is inevitable for such a major update to Audiobus, both in terms of starting with fresh code (and only having to carry a minimum of backwards compatibility stuff into the new code?) and an income stream to support the considerable development time involved. Considering what the Audiobus team have given to the iOS music making community over recent years, I don’t think we can have too many complaints about this approach.
Shiny new ‘bus
When you first load Audiobus 3, the basic layout of the main screen is similar to v.2.Various menu items appear along the top with access to the preset system located top-right. However, underneath the (initially empty) Input-Effect-Output slots are three new tab buttons; MIDI, Audio (the default view and the screen where you access all the existing between-app audio connections as in Audiobus 2) and Mixer.
If we stay with the Audio tab for a moment, as soon as you start loading apps you notice some further enhancements. First, for apps that are already Audiobus 3 compatible, the somewhat irritating ‘open this other app?’ requests seem to have disappeared. This popup was, I believe, more of an iOS thing than an Audiobus thing…. and while only a mild irritation, it is very nice not to see it quite so often.
Second, as you add audio apps into the various slots (and, as with AB2, new sets of Input/Effect/Output slots appear as you start to fill the existing ones), a strip of AB quick controls starts to appear (and grow) at the top of the screen. This is very useful as it gives you access to a range of key additional controls over the individual apps without having to switch to those apps themselves (in much the same way that Audiobus Remote did alongside AB2).
Obviously, the other new element within this (mostly) familiar Audio main screen is that you can now insert Audio Unit-based apps into appropriate slots. When you tap a slot to add an app, the popup app selection list now has a separate section for AU apps and, as with other non-AU Audiobus compatible apps, these are scrollable alphabetically. There is, of course, also the option to search for an app by name; useful if you are a member of AA (Appaholics Anonymous) and have more iOS music apps than you can count.
Obviously, multiple instances of AU apps are allowed and, as you attempt to add an AU app for a second time within an Audiobus configuration, you can choose either an existing instance or add a new one. These then become labelled (A, B, C, etc.) for ease of recognition.
Once you have an AU app loaded, tapping on it within the Audiobus main screen will open the AU UI within a separate window and filing the top half of the display. For instrument apps such as synths, a virtual MIDI keyboard appears in the lower half of the screen. This is all pretty straightforward and the AU ‘sub-window’ is pretty much what you might see in other AU hosts such as Cubasis…. although you don’t get the option to display multiple AU panels on the screen at the same time as offered, for example, by AUM.
We are obviously only a few days into the official life of Audiobus 3 but, in my own experience during testing at least, I didn’t experience any particular problems with the majority of the AU apps I tried to work with. I have not done much by way of formal ‘stress testing’ yet – just exploring AB3 in the context of what might be my own sort of a typical session – but I’d be very encouraged by what I’ve seen so far in terms of the AU support.
Otherwise, this screen – and configuring your various app chains – is going to seem like a very familiar process to current Audiobus users. That is, of course, a good thing in terms of maintaining any existing workflow processes that you have tightly honed.
Equally, whatever capacity your own choice of iOS hardware had for building up more complex collections of audio apps into an Audiobus configuration is not going to be magically transformed here; CPU restrictions will still remain. Having run a few of my own typically app collections on both Audiobus 2 and Audiobus 3, I’m not sure I noticed a huge difference on this front…. but if your experience differs from mine, then feel free to leave a comment below as I’m sure others would gain from any reader insights.
All mixed up
Given that Audiobus has always been about getting audio from various apps to play nicely together – and AB3 doesn’t change that core function – it perhaps makes sense to consider the new Mixer screen next. Indeed, as mentioned earlier, and given that audio management has always been the app’s key function, it is perhaps surprising that some sort of level mixing wasn’t added the Audiobus ecosystem before now. AB3 obviously addresses this.
In fact, the Mixer is actually very straightforward. For each Input slot within your project, your get a simple channel strip on the Mixer screen. During playback, each strip shows a real-time level meter and you get controls for level, pan, mute and solo. The small ‘note’ icon button allows you to send a ‘test’ MIDI ‘note on’ message to each input so you can easily judge what changes you are making without flipping back and forth between the instrument and the Mixer screen…. although the app icons at the bottom of each channel strip make that easy enough to do should you wish.
And, in terms of the Mixer, that’s about it; it’s basic, it’s focussed on the Input end of the system, and it is really intended to give you simple control over level and pan for each input source. It does its job with a minimum of fuss and it is great to see. It doesn’t, however, offer anything further than that.
The MIDI interface
Hitting the MIDI tab button opens up a further new screen and provides access to the other major new highlight feature of Audiobus 3; MIDI routing. In format and some basics of operation, this will already feel familiar as it features the same Input-Effect-Output routing format that we have all come to know and love from the Audio screen over the last few years. It is, of course, applied to MIDI data here though so the concept of an ‘output’ in particular, is something different.
Inputs can, of course, be from a suitable external MIDI device such as a keyboard or controller (providing you have suitable wired or wireless connectivity for that device). I had no problems on this front and Audiobus 3 saw (for example) my compact Alesis QX25 quite happily. Inputs can also be apps though…. and it this case it will be any app you have installed that can, itself, generate MIDI data and has been updated with Audiobus 3 support. As shown in the screenshot, that already includes a list of apps that are AB3 ready…. but hopefully this list will soon grow to include some of the more popular MIDI performance apps such Chordion, Navichord or ChordPolyPad. Arpeggiators, pattern sequencers or fully-fledged MIDI sequencers could fall into this category.
As I mentioned a couple of days ago, there are two new Midiflow apps that also fall into the ‘Input’ app category; Midiflow Keyboard and Midiflow Motion. I hope to do a separate review of all these Midiflow releases at some stage in the next week or so but it is easy to see how both of these could be very useful utilities for those whose workflow is built around Audiobus 3.
Outputs are also pretty straightforward as this could be any connected MIDI device or iOS music app that is capable to receiving MIDI data. This will, of course, include the dozens (!) of synth apps you have installed on your iOS hardware alongside the collection of drum machines, sample-based virtual instruments and any other apps (such as effects) that offer MIDI control of their parameters (some guitar rig sims for example).
The final category is MIDI Effects. For some users, this might not be a slot they dip into very often. However, arpeggiator apps would work here (MIDI note data from an ‘input’ is processed through the arp before being passed to an ‘output’ app such as a synth) and StepPolyArp is already Audiobus 3 ready to fit into this role. Equally, this slot could be more ‘utility’ orientated and the rest of the new Midiflow releases – Limiter, Monitor, Randomiser, Scales, Splitter and Transposer – are ready if you want to take the plunge.
My own experiments with the MIDI routing have so far been pretty basic – getting MIDI from my keyboard into a synth or sequencer – but it is easy to see how you could do something more than just these routine tasks. In particular, if you have multiple keyboards, or perhaps a full-size live MIDI keyboard controller for use in a live rig, used with the various Midiflow utilities, it’s easy to see how you could set up for keyboard configurations to give you control over multiple apps running on a single iPad as part of a live setup. The option for splitting a full-size keyboard could be particularly useful in this regard. Anyway, the system seems pretty easy to use and is implemented in a fashion that ‘fits’ the familiar Audiobus workflow.
That’s not to say there are not features it would be nice to see added and there is already a list on the AB forum pages from the development team that includes Bluetooth MIDI and MIDI Learn for the Mixer (for example). It’s clear that the Audiobus team have a development list that will be on-going to expand on the MIDI functionality included in this initial v.3 release.
We are all just starting a journey with Audiobus 3 and, while that journey has many familiar elements, it also has the various new ones that I’ve highlighted above. With the three key new top-level features – AU hosting, the Mixer and the MIDI routing options – while I can perhaps think of specific features it would be great to see added to each, what’s here and now seems to be working very smoothly. I don’t think any dedicated Audiobus 2 user is going to find the transition a difficult one and AB3 undoubtedly allows you to do things that AB2 doesn’t. Most importantly, it seems to work well from the off and that’s an observation the value of which should not be underestimated.
However, we also have another app that offers the same sorts of top-level features as Audiobus 3; the impressive AUM. Yes, you can do between-app audio connectivity, yep you can do some MIDI routing and, yes, you also getting mixing features. So do you need both apps if you are already using one? Good question….
The respective approaches adopted in AUM and Audiobus 3 do have their similarities but also their differences. For example, the MIDI routing options in Audiobus 3, on paper at least, would appear to be more flexible (and perhaps more obvious to the user?) than those currently offered by AUM. If all you need is to connect a MIDI input to a destination, then that might not matter… but the MIDI effects option in AB3 do offer something potentially useful for those that need it. That said, AUM has implemented MIDI control is a rather slick fashion…. You pay your money and you take your choice….
In terms of audio routing, basic tasks such as getting audio out of one app, through an effect (or three) and into another app (or to a hardware output) are perhaps not so different. Both approaches work even if they are physically presented in different graphical fashions… and both apps offer AU hosting. Perhaps where AUM scores here is in the greater flexibility it offers with the provision of send/group channels? This is much more of a ‘virtual mixer’ feature and, while perhaps only of interest to a sub-set of users, it is undoubtedly a powerful option.
Indeed, while this is probably me putting words into the mouths of the two development teams, I think this last point perhaps hints at a somewhat different design philosophy? Audiobus 3 does what Audiobus has always done; it provides a system for connecting various iOS music apps… it just now does that with MIDI as well as audio and with basic mixing features. In contrast, AUM as always struck me as being designed as a ‘virtual mixer’ environment and that happens to be built specifically to host iOS music apps and handle their audio and MIDI connectivity. As a mixer, AUM offers much more than Audiobus 3 at present and also includes a suite of its own audio effects – EQ, compression, etc. – that provide virtual elements of a hardware mixing console.
AUM is currently priced at UK£18.99/US$19.99 and Audiobus 3 is UK£9.99/US$9.99. Neither are ‘expensive’ items in the modern world of music technology nor expensive when compared to your iOS hardware in the first place. Users will decide for themselves but, personally at least, I think AUM’s more sophisticated mixer features more than justify the price difference.
Given all of the above, if your current workflow is built around Audiobus 2, I think opting into Audiobus 3 is going to be a pretty easy decision, even if just to get access to the AU hosting and you leave the MIDI and mixing elements untouched (although that would be a shame). Equally, if you are a dedicated AUM user, then I’m not sure Audiobus 3 gives you any really compelling reasons to migrate. That doesn’t mean it wouldn’t be useful (or simply interesting) to own though… and long-standing iOS musicians may well be more than happy to shell out to show continued appreciation and support for what Audiobus has contributed to iOS music technology.
Two questions are perhaps less clear in terms of answers though. First, do you really need both Audiobus 3 and AUM? Second, and perhaps a somewhat more fundamental question, can you manage without either now we are seeing AU gain ground?
Over a suitable beer amongst a decent sized group of iOS musicians, both of these questions could form the basis for an evening’s long ‘discussion’ (or a flame-fest on a suitable forum). I’ll just offer a few (probably obvious) personal observations here…..
Either or both? If your primary use of either Audiobus or AUM is simply to link together a few of your favourite iOS music apps (that is, you are not pushing the envelope of iOS music tech or your hardware with some complex, mega-multi-app setup on a regular basis), frankly, I think either app would be more than capable of getting the job done. If you are already a user of one or the other, then it would perhaps seem obvious to stick with what you know (with a move to AB3 if you are currently an AB2 user). Power users might feel different…. there are things that each app can do that the other cannot…. but they can also be used together to get the best of both worlds…. and, as mentioned above, neither is a massive financial outlay in music technology terms.
What about neither? This is, perhaps, the more difficult (interesting?) question. My interest in iOS music tech is really on two fronts; music composition and recording. As such, my primary ‘app glue’ is provided by my DAW/sequencer of choice (Cubasis in my case). While I reach for both Audiobus and AUM on occasions, with the advent of AU, and for my types of music making, that’s become less often as more AU apps have started to appear. However, if you are an iOS musician whose focus is more around live performance, perhaps a DAW/sequencer isn’t always (at present anyway) the best hosting/routing platform; AB3 or AUM are perhaps better designs for that sort of task?
This second question does, however, say something about how iOS music technology has evolved since the release of Audiobus 2 back in July 2014. At that point in time, I think it is absolutely fair to say that AB2 was considered an essential purchase for the majority of iOS music makers. Nearly three years on – with competition from AUM and the arrival of a credible plugin format for iOS – I’m not sure that’s still the case.
Don’t get me wrong; Audiobus 3 is an impressive app and will, for many iOS musicians, be an instant purchase. It can still fulfil an important role in an iOS music workflow. But it is a sign of the times that it perhaps isn’t quite so ‘essential’ as it once was. The Audiobus team haven’t done anything wrong here…. other than, by providing an ‘app glue’ solution, made Apple realise that iOS needed what OSX has already got; a viable plugin format for music software. Apple – admittedly in a somewhat cack-handed fashion over the last 18 months – are gradually providing that with AU.
I do wonder if, eventually, when AU becomes the dominant format for all virtual instruments and effects, if we are perhaps heading for two types of ‘AU hosts’? We have one of them already; DAW/sequencer apps such as Cubasis or Auria Pro (and others). These will replicate our established workflows from the desktop environment.
The second is a ‘virtual mixer’ that hosts AU apps. To an extent, that’s exactly what AUM and Audiobus 3 already provide. The concept is perhaps somewhat more clearly expressed by AUM’s design at present (indeed, the App Store description calls it just that) but it could just as easily be visualised in a more conventional UI like the mixer elements of Cubasis or Auria Pro to make it crystal clear to those transitioning from the hardware world. As with AUM and Audiobus 3 now, this ‘virtual mixer’ could be used to feed audio to a DAW but, equally, I suspect it would also appeal to the live performer, particularly if it supports multiple audio outputs on a suitable audio interface and that can then be sent off to your live mixer/PA.
Again, AUM is perhaps already there and Audiobus 3 is moving in that direction…. but, if all these hosts had to handle was AU plugins – and not, in addition, the various flavours of Audiobus or IAA compatibility we also currently depend upon, then it might, eventually, become a less complex world for us all to inhabit. Yes, this does require Apple to really nail the AU spec under iOS for it to become a reality…. but that time is going to come.
If AU does become ubiquitous, then presumably the need for apps to also be ‘IAA compatible’ or ‘Audiobus compatible’ will disappear. In turn, that might mean that the purpose of Audiobus itself has to be re-focused. Maybe, in part, that’s what Audiobus 3 is already doing; transitioning towards a role as an audio/MIDI routing/mixing ‘host’ for AU-based software? The functions that Audiobus has always offered, and now offers in an expanded format with MIDI, remain both relevant and extremely useful. What’s perhaps becoming less vital is its other role as a dedicated hosting format in its own right.
That is, of course, something for the future (although perhaps the not too distant future) and, right here, right now, we are still in a mixed format world combining Audiobus, IAA and AU as formats for hosting music apps. In that context, Audiobus 3 can easily be a very useful part of your iOS music making present.
Whatever flavour the iOS music future might hold, personally, I hope that the Audiobus brand – and the development team itself – can bring their considerable expertise and insight to bear on it. However Audiobus might evolve further over the coming year or two, those last five years or so of Audiobus and Audiobus 2, mean we (as an iOS musician community) have a heck of a lot to thank them for.
The advent of AU, albeit arriving in fits and starts, represents a fundamental change to iOS music technology since Audiobus 2 was released in 2014. Audiobus 3 therefore arrives into a very different world. For current AB2 users, the new functionality of AB3 will be both appealing and very familiar and I’m sure the majority of regular users will be more than happy to invest in the new version. Dedicated AUM users might be intrigued and also want to explore but, with the exception of perhaps a small minority of users who like to use both utilities together, many AUM users will perhaps be happy to stick with what they have got.
For those just starting out on their iOS music making story, despite the expansion of AU, right now, Audiobus 3 is still most certainly relevant. It is perhaps the most accessible means of linking multiple apps together and experimenting with the possibilities that can provide. It is also very competitively priced and the new options in this version – AU hosting, MIDI routing and basic mixing – have been seamlessly integrated into the audio routing/connectivity features Audiobus is famous for. Audiobus is an iconic app in iOS music making history. It deserves that status and, while it might not be quite such an ‘essential purchase’ in 2017 as it was in 2014, v.3 is still going to be a valuable tool for considerable numbers of iOS music makers.