Ops review – Jonathan MacKenzie brings his take on a modular synth for iOS

Download from iTunes App StoreI make this confession regularly on the blog – I’m no great expert when it comes to synth programming – and such a confession is all the more apt when we are taking about not just programming synths but actually designing your own synth from scratch. Yes, modular synths, of which we have a good few examples available under iOS, are something that are, at any detailed level, well out of my comfort zone.

That doesn’t mean I’m not interested though and I’ve reviewed a number of such apps here on the blog in the past with the obvious leading candidates being apps such as Audulus, zMors Modular and Analog Kit (oh, and Caustic has a rather neat modular synth instrument included as well). Both Audulus and zMors Modular have been updated fairly recently, while Analog Kit is perhaps overdue a bit of TLC. That said, these are all very cool apps, albeit appealing to a very particular (niche within a niche) audience.

As with virtual guitar amp design software such as BIAS Amp, one of the beauties of software-based modular synths is that there are no actual electronics and soldering irons attached to the process. That means no expensive components to blow up and no danger of death by electrocution; these are good things in my eyes. Equally, done on a touchscreen – and with the right approach to the graphical interface – and even a synth numpty like me can at least have a go at modular synth design…. even if I have little (er…. no) idea what I’m actually doing. Skilled or not, it’s a platform that the mildly inquisitive can enjoy exploring and the die-hard synth heads can get fully immersed within.

Ops – a modular synth app for iPad and iPhone.

All of which is a fairly long preamble into a review (as best as I can given the comments above) of a new modular synth app; Ops from developer Jonathan Mackenzie. The App Store blurb indicated Ops is ‘designed to make it easy to create and explore sound interactively with a touch screen’ and, while that doesn’t guaranteed that even a synth-o-phoebe like me will cope, it does suggest that Jonathan is trying to make synth design as accessible as he can. Has he succeeded? Let’s find out….

Hop into Ops

Let’s start with some basics. Ops is a universal app, requires iOS10.0 or later and is a 92MB download. The app is priced at UK£9.99/US$9.99. MIDI in is supported, both for note and controller data, if you want to control your synth designs via external hardware. Audiobus and IAA support are also provided.

Ops operates over two main screens. The Projects page opens on start-up and this is where you can browse any existing design, whether those be those supplied with the app to get you started or ones you have created yourself. Options here include the ability to load, save, rename, export and import designs.

Ops Project screen where you can browse and load your existing designs.

When you open an existing design, or start a new project, the app switches to the other main screen; the Ops screen. It’s here you can build your own designs and then play them, and you toggle between these two states via the Edit and Play buttons located top-left. Other buttons here allow you to ‘fit’ the current design to the full screen and to ‘lock’ the design in place (this means you can’t move the design around on screen or zoom in/out). Top-right is the ‘I’ button (which opens a brief introductory manual) and the projects button that takes you back to the Projects page.

Simple Ops

The bulk of the rest of the Ops screen is where you can build your designs and you do this by dragging and dropping ‘ops’ (operators) from the selection panel at the base of the screen. This panel is scrollable as there are more ops choices than fit even on the span of an iPad pro screen. That’s a good thing by the way as it means you have plenty of individual building blocks to work with :-)

The Edit screen includes a scrollable list of all the available ‘ops’ (modules) at the bottom…. and there are plenty of choices to be found.

The ops are divided into colour-coded groups – controls, patterns, links, timing, sources, envelopes, filters, effects, maths and misc – which provides a nice visual cue as to what each ops is about as you drag and drop to build your design. If you want a brief description of a specific op, then just tap and hold on it; a pop-up windows will appear with a short text description. These are helpful as you find your feet but perhaps don’t contain much by way of technical detail if you are struggling to understand how to make the op work in the context of the overall design you are constructing.

Within the main area of the screen, as you build a design, you can use the usual touchscreen gestures to move around the design itself (if, for example, it is a complex one and fills more than you can easily see on the screen at one time) and also zoom in/out if you need to see more detail of a specific portion of the design.

Tap and hold on a specific module and a brief description will appear to get you started….

Compared to (for example) Audulus, one obvious visual difference you might see in the Ops screenshots shown here is the lack of any patch cables. Ops is deliberately ‘cable-free’ in a visual sense and the order of the placement of individual ops themselves dictates the signal flow, which moves from left to right, and the right-most op is always the final point of output. You can make exceptions to this using the (red coloured) Send and Receive ops and this is described in the built-in introductory manual.

Indeed, this is pretty much an essential read – as is the embedded video introduction – as, between them, they give you a starting point for the key principles of the design process. In short (and because I’m not qualified to do ‘in long’), this includes options for adding and deleting ops, duplicating elements within your design, and combining individual ops in various ways.

The Ops list includes the interesting Input module, allowing you to use audio sources – including from other apps – as your sound source for processing within your Ops designs.

OK, I still don’t make any claims about really understanding how best to combine these various design elements to build an actual working synth, but what I can say is that the UI is both pleasing on the eye and has a certain sense of logic about it. I can see both pros and cons to the cable-free approach. It certainly makes for a less busy display but, equally, I suspect there are occasions when seeing the visual link between components can help you follow exactly what a design is doing. Maybe an option to toggle on a graphical representation of the connections might be a nice addition in an update at some point so users have the choice, even if the default behaviour is ‘no cables’?

My only other comment is that the Edit ad Play modes are ‘separate’ in the sense that, while in Edit mode, you don’t hear any audio from your design. So, if you are tweaking the design, or adding new components, you do have to keep toggling back and forth between Edit and Play modes to test out what a change might be doing. This is a very ‘clean’ approach but some users might find the constant to and fro a bit wearing in a complex building project.

Ops includes a number of different filter types amongst its options.

Here’s one I (didn’t) build earlier

I had a lot of fun exploring the supplied presets and they do enough to make it clear that Ops is capable of producing all sorts of interesting – as well as weird and wonderful – synth-style sounds. Once your design is done – and you hit the Play button to actually use the instrument you have created – a small oscilloscope graphic appears bottom-right and shows a real-time display of the output waveform. This is both rather cool and, when you start to build more complex design, quite instructive.

Ops includes support for Audiobus when your synth is ready to use in a wider project.

However, when it came to building my own design from scratch….? Well, let’s just say I didn’t get too far. Yes, laugh as much as you like, but I don’t think I’ll be able to give up my synth preset apps just yet.

There is a more serious point here though… or maybe even two. First, while the built-in help, project files and introductory video are all nicely done, I’m not sure there is really enough detail provided to get the ‘interested but uninformed newbie’ (that’s me) off the ground and running without a lot of head scratching. Perhaps that suggests that, second, this is an app that is really aimed at the more experienced/knowledgeable synth-geek than me.

I had no issues using Ops via Audiobus (as shown here) or IAA. Note also the small oscilloscope display located bottom-right when in Play mode…..

That’s not a criticism of the app in any way but perhaps just the reality of modular synths; to get the best out of the potential, you have to have a solid grounding in the principles of synthesis. Still, with time, it would be nice to think Jonathan might add some further tutorial videos explaining some of the more obvious elements of basic synth design within Ops. For example, even an introduction to something as fundamental as getting external MIDI data into the app would be helpful. Or maybe a video that walks the user through building a simple synth from start to finish?

IAA support is also included…. as shown here within AUM and with Ops alongside some other modular synth contenders :-)

I think this could significantly widen the potential audience for the app…. and even a synth beginner like myself can see the potential in the broad selection of individual ‘ops’ that are already offered within the app. For example, amongst the Sources group of ops is the Input op. This allows you to feed in an audio input to the app from an external source or another app via IAA or Audiobus. Your Ops design can then be used to modify/process this audio input. This could open up all sorts of possibilities for the more sonically adventurous.

In summary

OK, so I didn’t get too far with my own designs so, in terms of just how far someone more qualified than me might go with the tools Ops provides, well I’m not sure I can give a definitive opinion. My educated guess, based upon my dabbling with other iOS modular apps, is actually pretty far….   but I’d be more than happy to see some user comments below if you have already taken the plunge with Ops.

What I can say is that I do like the underlying UI. It’s visually attractive and the left-to-right signal flow makes design structure fairly easy to follow. That doesn’t seem to stop you creating complex designs though and the Send and Receive ops mean you can easily build convoluted audio signal flows if you wish.

Perhaps two comments are worth adding by way of conclusion. First, as with all modular synth apps, this is not perhaps an app for the synth newbie. If (like me) your idea of a good synth is one with lots of presets and a filter and LFO to tweak then perhaps Ops (or any modular synth) is not really for you just yet.

Second, iOS already has a number of very good modular synths available. For example, Audulus – which is perhaps the ‘daddy’ of these – is well established and has a massive feature set. It is also about twice the price of Ops. Perhaps a more direct comparison is with zMors Modular as it is a similar price to Ops. It is also well featured and does, I suspect, have an established user base. Ops is likely to be appealing to exactly the same user base.

In both cases, this is an interesting audience because, while Audulus or zMors Modular owners might not need another modular synth app if they are already well in tune with their existing options, you do have to be pretty hard-core and geeky about your synths to have got to that stage in the first place. And, if that’s you, then the temptation of a new modular synth environment to explore might be one that you have absolutely no reason to feel like resisting. Ops is, after all, in the wider scheme of everyday life, a pretty modest investment.

Yes, I like Ops a lot and I can see considerable potential (but, heck, what do I know?). Not a casual purchase for those with a casual interest… but certainly worth a serious look if you are a serious fan of synth building.


Download from iTunes App Store

Be Sociable; share this post....


    1. Hi John (and all;-)

      As one of the happy beta-testers and otherwise relatively well versed in modular synth approach in general (aside the usual ios-suspects ivcs3, audulus, model15 etc etc), id say this is probably the most user-/beginner-friendly of them all – but still youll need some basic understanding of the underlying principles to fully take advantage of this way of ‘diy’-ing it – on the other hand i simply cant imagine a more friendly introduction than Ops into this strange and wonderfull ‘paradise’ of modular-based synths. But almost anyone of any skill-level will be able to ‘make something’ here… Cant praise it high enough and i really really hope it will become both bigger & better over time! This is one app i really hope gets the user-base it ‘deserves’ so continued development is possible.
      One thing that could certainly ‘ease the pain’ is plenty of tutorials like you mention – cant argue with that – then again, theres a ton already on the basics of modular-principles online but app-specific ones is offcourse preferrable.
      Okay – Over & Ops from here;-)


      • Hi K, thanks for your input here…. I’m sure that will be of interest to plenty of potential purchasers…. Thanks and very best wishes, John

    2. Eustressor says:

      At the very least, it seems from the video you can create a sonic mayhem maker in the vein of Dr. Ohm and Noisemusick pretty easily, so that’s a win for me – stumbling across more conventional sounds would just be icing on the cake.

      Definitely looks like a “where did the last three hours go?” rabbit hole synth, and that’s always fun :)

      • Yep…. Most of the time I was just stumbling around…. but there are plenty of cool sounds to be had. Since pressing publish of the review the developer has been in touch to say more tutorial materials are planned…. so that would obviously be a good thing for newbies to the app :-) Very best wishes, John

    3. I’m intrigued by this app and agree with Eustressor’s assessment/impression. Only thing keeping me from hitting the buy button is that I’ll hit a learning curve brick wall like I did with Audulous 3. I don’t regret buying that one because I know it’s capable of amazing things… but I simply don’t know how to get past the first hurdle beyond simply using other’s patches, or making very primitive patches myself that end up being poor replicas of other apps.

      The clean look of this one does look somewhat intuitive to me, but John’s confusion and stumbling give me pause. I mean with his vast hands-on experience with iOS music apps have him scratching his head somewhat… I well is a novice like myself going to fare?

      • Bought this… like it. Already getting cool sound. Took nearly an hour to start clickin’ with it, but it’s more accessible and intuitive than the other modulars I’ve tried. :)

    4. Dion Simons says:

      Love the design and the sounds! Yes, need the presets and time to learn.

    Speak Your Mind