Manufacturer: Waldorf Music GmbH
Release Date: 1998
Type: Digital wavetable synthesis
Reviews: Vintage Synth | Sound On Sound | Sonic State
The Waldorf MicroWAVE XT is an incredible digital wavetable synthesizer from the late 1990s.
The original Waldorf MicroWAVE was groundbreaking in that it brought wavetable synthesis + analog filters to the masses, at an affordable price (notwithstanding the PPG Wave before it). Unfortunately, the Waldorf MicroWAVE’s interface left a lot to be desired as it was comprised of buttons resulting in lots of menu diving, making real-time tweaking extremely difficult for most.
Enter the Waldorf MicroWAVE XT, a 44-knob-laden wavetable synth designed for real-time tweaking from the ground up. This is Waldorf’s answer to the critics of the original MicroWAVE when it came to real-time programmability, and with the MicroWAVE XT, they’ve delivered in spades. Sure, it may not have analog filters, but if you can get past that you will discover a synth that can take you on sonic journeys unlike any other before it.
First, lets talk about the sound: The MicroWAVE XT has 2 digital oscillators that output the standard basic waveforms (sine, square, sawtooth, triangle); however, the strength of this synth lies not in subtractive synthesis, but in its use of wavetables and wavetable synthesis in general. With digital wavetables, you can create some incredible patches that traditional analog subtractive synths simply cannot reproduce.
Having the ability to “sweep” through a wavetable can generate additional harmonics, textures and sonic character that might otherwise lie undiscovered within the waveform itself. Besides the wavetable generators you’ve also got ring modulation, a noise source, FM and oscillator sync modes. Needless to say, the XT is a synth that excels at creating “new” and “unheard of” types of sounds, and is a sound designer’s dream when it comes to sonic experimentation.
The Waldorf MicroWAVE XT has 2 filters with multiple slopes (6/12/24 db) and multiple filter types: Low Pass/High Pass, FM Filter, Sin (x)-LowPass, Waveshaper, Double LP/HP, 24/12 Band Pass, Band Stop. The number of filter types is amazing to say the least, and combined with the various wavetable options, leads to a huge amount of sound creation options. For example, let’s say you find a sound you like with the low-pass filter; changing to the “waveshaper” filter type for instance, completely alters the sonic character of the patch such that it may become unrecognizable compared to its earlier incarnation. One can spend endless hours simply tweaking sounds based on filter type and wavetables alone.
The Waldorf MicroWAVE XT has 2 LFOs with various shapes including sine, triangle, square, sawtooth, random and sample & hold modes. These LFOs lend additional sonic motion to the sound, and can be easily routed depending on your needs via the in-depth modulation matrix. The XT’s modulation matrix has 16 slots and is simple to use, flexible, and provides a variety of sources and destinations for routing including pitch, volume, filter, aftertouch and much much more. Furthermore, there are 4 mathematical equation “modifiers” which can further manipulate sounds beyond their original intention, leading to completely new and unrealized creations.
Envelope-wise the MicroWAVE XT packs a punch: 4 envelope generators, 2 of which are traditional ADSR, and one of which is an 8-stage loopable EG, the other a 4-stage. With so much envelope flexibility, its easy to craft and adjust sounds that change character over time. It’s also easy to adjust these options on the fly when performing live, helping to bring a more “organic” element to the sound creation process.
The MicroWAVE XT also features a cool programmable 16-step arpeggiator, and features 16-built in patterns which can be used as a basis for further ideas. The patterns are actually quite musical and lend themselves well to sketching out new melodic ideas or bass lines, or for creating ambient soundscapes that build over time.
Effects-wise there are the usual suspects: chorus, flanger, overdrive, delay, panning delay etc… but what’s sorely missing is a reverb. The lack of reverb is particularly disappointing in a synth of this caliber, particularly as it excels at sonic experimentation and ambient soundscapes. This can be alleviated by running the XT’s output into an external reverb unit (via DAW, FX box or even another synth’s effects unit), but in my opinion its an oversight which could’ve made this synth just that much better.
When it comes to tweaking live, as mentioned the Waldorf MicroWAVE XT has 44 knobs to work with. Tweaking on the fly is fast, intuitive and easy, as nearly every immediate function has a knob assigned to it. That said, menu-diving is required at times but the options are logically categorized and laid out, and the LCD screen is sufficiently big to display various parameters in an easy to read fashion.
Note that the knobs are endless encoders and may be prone to glitchiness if the synth is stored/not used for long periods of time, due to the lubrication material hardening. This can usually be alleviated by turning the knobs one way or the other for approximately 50 rotations to loosen things up; if not, a good internal cleaning/lubrication or knob replacement may be necessary.
That said, at times I feel like the Waldorf MicroWAVE XT has a mind of its own, and can be hard to “control” or get it to do what you want in a precise manner. Whereas with some synths its easy to be up and running creating new sounds in minutes, with the XT the patch creation process and finding that “sweet spot” can often require a substantial amount of tweaking. This can initially be frustrating for some, but with time you start to learn how the synth behaves and operates, and get better and faster at creating the sounds you’re looking for.
Lastly, the standard Waldorf MicroWAVE XT model is 10 voices. Surprisingly, the XT allocates its 10 voices in a very efficient manner such that I haven’t encountered any voice stealing or abruptly cut-off notes (ie long release times) when creating sounds. If you have a hankering for even more polyphony though, there are (rare) 20-voice expansion cards available (usually via eBay at a premium) which gives you 30 voices total. Some enthusiasts are even trying to get additional expansion cards manufactured via DIY/crowdfunding projects, such as this possible ENCORE voice expansion card upgrade. There is also a 49-key keyboard version of the XT available, called the XTk.
Overall, the Waldorf MicroWAVE XT excels at what it does best — wavetable synthesis, with real-time control. No, it doesn’t have analog filters but it is proudly digital and can generate wierd alien sonic landscapes, soothing ambient space drones, bitcrushed experimental noise, and everything in between. While it may take some initial time investment to learn how wavetable synthesis works and how the XT in particular operates, this is certainly a synth with its own distinct sonic character that can take you into uncharted sonic territory.
If you have any interest beyond traditional music making, in sonic experimentation and sound sculpting, the Waldorf MicroWAVE XT will certainly give you plenty to work with, and leave you highly satisfied with the sounds it can produce. That said, if you can find a 30-voice unit at a great price, consider yourself a very, very lucky person and snap it up right away! 🙂
|Interface||44 knobs, 10 buttons, 14 LEDs|
|Polyphony||10 voices (expandable to 30)|
|Oscillators||2 oscillators / 2 wave generators per voice of DSP wavetable synthesis.
64 wavetables available incl. saw, tri, sine, square
1 Ring Mod; 1 Noise Source; 1 FM; Osc Sync
|LFO||2 LFOs. Sine, Triangle, Square, Sawtooth, Random, S&H|
|Filter||2 filters. 6/12/24 Low Pass/High Pass, FM Filter, Sin (x)-LowPass, Waveshaper, Double LP/HP, 24/12 Band Pass, Band Stop|
|VCA||4 Envelope Generators (2x ADSR, 1x 8-stage loop, 1x 4-stage)|
|ModMatrix||16 slots + 4 modifiers|
|Arpeggiator||Programmable (16 steps, 16 patterns)|
|Effects||Chorus, Flanger, Autowah BP, Autowah LP, Overdrive, Delay, Mod Delay, Panning Delay, Amp Mod|
|Keyboard||XT model: rack unit, no keys
XTk model: 49 keys
|Memory||256 internal patches, 64 external card|
|Control||MIDI in/out/thru (8 multitimbral parts)|
Two questions: I had reached out to Waldorf, but looking to possibly get some replacement knobs… AND encoders need cleaning. I need to be able to open it properly. I’ll petition them again… perhaps via twitter?? Thanks for any help! -antfactor
Hey there, I’m actually looking for some replacement knobs as well for my XT as many have crumbled to dust. If you find anything, let me know. I heard Mouser Electronics may carry similar parts.
Good evening everyone. 🙂
My MicroWave 2 is having trouble:
The control knobs don’t operate properly anymore.
The only remaining active controls are the on/off push button and the main volume.
I thought the encoders and switches had to be cleaned so I opened the synth and used contact cleaner to process the switches and encoders.
It didn’t do much except that the encoders move more freely.
Has any one a suggestion about how to get the schematics?
I suspect there is a serial data link problem between the control board (the knobs) and the synth engine card (the board with the jacks)
Thanks for any help. 🙂
Hi Luc, sorry to hear about the troubles you’re having with your XT.
Here is a service manual for the control board I found: https://electro-music.com/forum/phpbb-files/d_mwxl20_109.pdf
You could also try asking on this FB group about synth repairs, they may have some tips: https://www.facebook.com/groups/vintagesynthrepair
There is this thread with some knowledgeable people that could also help, perhaps post a message or start a new thread: https://www.gearslutz.com/board/electronic-music-instruments-and-electronic-music-production/1316079-help-microwave-xt-accidentally-installed-old-firmware-over-new.html
Best of luck!
Your XT is expanded?
Hey there, just saw this comment. No, my XT is only 10 voices. But, there are 30 voice expansion cards still for sale these days.