Waldorf: Iridium Synthesizer & Processor

Let’s get this out right up front: Waldorf’s Iridium is a deep, complex instrument and processor with tons of new technology under the hood, both in terms of its synthesis engine and its architecture. Yet despite all that complexity, navigating the Iridium is surprisingly easy and intuitive, thanks to a brilliantly thought out user interface that uses a combination of hardware knobs with a touchscreen interface (about the size of a large smartphone) built into its front panel. The touchscreen is very hi-res and the graphics are both informative and super cool to view, but more than anything else it’s the touchscreen that makes this synth feel like the future landed in my studio today – a bit like watching Kubrick’s 2001 when it came out in 1968. However, despite this instrument being easy to navigate, it is not easy to understand or use beyond just playing and fiddling around a bit with the presets. This is because it is so deep and new, and many of the concepts here will be foreign to most users as they are so cutting edge.

But, let’s go back to the beginning here. The Iridium is a desktop synthesizer based on Waldorf’s flagship Quantum, which is like a turbocharged version of all Waldorf’s previous synths going way back to the PPG Wave, where wavetable technology – the core of this and most of Waldorf’s other synths – began. The PPG Wave was designed by Wolfgang Palm and was totally unique when it came out in 1981. It combined digital wavetable oscillators with a more traditional analog synthesis path of voltage controlled envelopes and an analog voltage controlled filter. It was a big hit at the time, and used extensively by artists like Thomas Dolby, Tangerine Dream, and Tears for Fears. When Waldorf took over PPG’s wavetable technology, they brought it to the masses first with the MicroWave, and then a series of Wave synths up to the more recent Blofeld model. But only the first MicroWave retained the PPG’s analog filter; subsequent models were all-digital – with the filter being DSP-driven – until Quantum, which brought an amazing amount of new technology to the Wave line and brought back the analog filter. It was a hit, but pretty expensive at just under $4500. I’ve only seen two of them: One at NAMM, and one at soundtrack composer Charlie Clouser’s studio who raved about it – look for his interview this issue [#141]! I’d been trying to audition one but to no avail. Then Waldorf announced Iridium, the desktop version of Quantum with even more new technology and a more affordable price tag of $2500 – still not cheap, but at least in the realm of possibility for serious synthesists. However, there is one big difference between Quantum and Iridium besides the form factor: The filter is digital, not analog. For some purists, this is a deal-breaker, but the DSP filter allows much more versatility as it’s true stereo, has HP/LP/BP/notch modes with models for the Nave, Largo, PPG, Quantum, and state variable filters. One other big difference between Quantum and Iridium is that while lacking a keyboard, Iridium has 16 pads so you can play directly from the instrument if you want a stand-alone box. This can be a lot of fun and can help you break away from the normal melodic impulses you might have when using a standard keyboard. Okay, with all that said  let’s dig into Iridium a bit deeper.

Let’s start with the oscillators. There are three full oscillators as well as six LFOs. Each oscillator can work in one of five modes: Wavetable Oscillator (like the classic PPG), Waveform Oscillator (virtual analog), Particle Generator (which uses aspects of sampling and granular synthesis), Resonator (which is a physical modeling mode), and the new Kernel mode (which can link up to six oscillators through FM at audio frequencies). Whew! Accessing all these functions is fairly straightforward and intuitive, but with some of the newer options presented here, understanding what’s going on isn’t easy. We’ve already touched on the filters, but I should add that there’s also a Digital Former module that does additional filtering (plus things like bit crush, ring modulation, etc.), and can do more sophisticated filter routing and modulation within the module. Speaking of modulation, in addition to the six LFOs, there are six envelope generators, and what they’re calling a Komplex Modulator that is a combo of LFO and envelopes with a user-definable shape. The possibilities for sound design and processing within Iridium are vast and deep! The downside is that you will need to dedicate some time to learning this synth. Despite the GUI being really easy to navigate, I often found myself a bit dazed and confused trying to modify a preset patch because there are so many different parameters. With great power comes great responsibility! Speaking of patches there are over 1000 presets for Iridium, and those are really easy to sort through as you can group them with a variety of filtering options, such as type of sound, sound designer, etc. Plus, you can store a total of 7000 patches! There’s also 2 GB of built-in/onboard flash memory for samples.

I can’t say enough good things about Iridium’s touch screen interface. It’s super cool, informative, and useful, making the operation of this instrument really fun – I feel like I’m in a cool sci-fi movie. Besides, it’s everything you’d expect in terms of GUI, including the 3D waveform and wave mapping displays.

After spending some time playing around with Iridium, both as a stand-alone unit and with a keyboard controller while auditioning and fiddling with the vast preset library, I wanted to try using Iridium as a processor and run audio through its external inputs. This seems like it would be of interest to lots of Tape Op readers, and was one of the main reasons I wanted to try this unit out. For something as deep as the Iridium, I found the manual to be surprisingly light and was unable to figure out some advanced audio processing options. But luckily, they have great customer support, so I was able to get some tips from Rolf Wöhrmann, one of the primary designers of the instrument. He gave me some clues on routing external audio through the Iridium. There are two basic modes here: One is to just route your audio through Iridium’s FX chains, digital filters, and Digital Former (much as you might with a modular synth rig). The other, more advanced, way to use Iridium with an external audio signal is to apply the Live Granular mode with one of Iridium’s three oscillators, in which your external audio signal actually becomes the audio in the oscillator when in Particle mode. This opens up vast possibilities for sound design and experimentation beyond what most synthesizers are capable of. But again, with great power comes great responsibility. While it’s complex to set up the Iridium as a processor, once I got it working, I have to admit I was pretty blown away. You can do things to audio with this unit that nothing else I’ve seen can really do. There are lots of great filtering and granular synthesis plug-ins available that I have loaded into my DAW, like Soundtoys Crystallizer, Eventide Crystals [Tape Op #138], Audiority’s GrainSpace [#121], and others that I can call up in seconds that stay with my session and project. There are also a lot of fairly affordable Eurorack modules that will do very similar processing, like Mutable Instrument’s Clouds for instance. But the ability to do so much different processing at the same time with Iridium, and its well thought out interface/GUI, is really unique and powerful. While I was initially a bit skeptical about Iridium’s digital filter, when running hi-res audio through it, I could really hear what was happening and realized how powerful a 16 voice stereo filter can be. There were no digital “stepping” artifacts present either, and control of the filters was very smooth with an “analog” feel. But the complexity of routing audio through Iridium is a bit of a hurdle to use it in that way. In lieu of the manual’s lack of detail about how to use Iridium as an external audio processor, I think that Waldorf would be well served by including a good handful of presets with Iridium specifically for processing external audio to make it easier for users to get started. My Dave Smith Evolver [#35], for instance, ships with a handful of presets for processing external audio, so it’s much easier to get started and tweak when running sound into it. Lastly, before I leave the audio input section, I should add that Iridium can also sample and edit external audio sources, to then use those as sound sources within Iridium’s sound design topology – another advanced feature that very few synths provide.

In conclusion, Iridium is a very advanced and complex piece of musical technology, but it’s probably not for everyone. While other tools can do a lot of what Iridium does, there is nothing on the market that does all of this in one compact box with such a well thought out interface and GUI. For producers and composers who want to dive deep into sound design, this unit’s vast possibilities and compact desktop form factor will be perfect.

I was a bit sad to send the Iridium back and had seriously thought about buying it, but in the end couldn’t justify it for my uses, or my studio. The price tag was still pretty high for me,and the complexity and lack of a keyboard were daunting for visiting artists and producers – so aside from me, the Iridium just didn’t see much use in my studio. I’m not that deep into sound design (on a professional level) and tend to look more for instruments that are relatively easy for clients to play. The lack of a keyboard is also another factor for me, and I felt that Waldorf’s own Blofeld (with or without a keyboard) is a much more affordable way to get into a hardware-based wavetable synth – even though it’s nowhere near as complex, powerful, and rich. Waldorf also makes the excellent Nave iPad app that sounds really amazing and is only $20 – less than one percent the cost of Iridium. And while on the subject of iPad apps, I’m a huge fan of Wolfgang Palm’s sadly discontinued PPG iPad apps – enough so that I have kept an older iPad with a legacy OS just to run these apps. Wolfgangpalm.com was acquired by Brainworx/Plug-in Alliance, and they no longer offer all the PPG products (at the time of this review); here’s hoping they change that soon. Although Iridium is much more powerful, with more voices than any of the iPad apps at this point, all of these apps do sound good to my ears. In the end, both boxes (Iridium and iPad) use DSP for the filter, and I feel like if I’m going to invest in hardware, an analog filter is something I’d like to have (even though I was very impressed by the sound of the DSP filters on the Iridium). Iridium has a lot of lower-priced competition, much of it from Waldorf itself, even if it’s not the flagship that Iridium is. As users in this era of modern synths, we are lucky to have so many great options to choose from and to have companies like Waldorf making so many groundbreaking new instruments.