Released
March 2015 (latest batch)
- A DIY kit that's not for the faint-hearted but certainly not impossible to assemble, the LXR from Sonic Potions is a drum synthesizer that's worth the effort. In appearance and functionality, it resembles the Elektron Machinedrum or even Octatrack, yet it's definitely its own device. A great deal of parameters can be used together to create a huge range of sounds. It's a 16-bit, 44.1-kHz digital synth that uses an SD card for storing patterns, sounds and waveforms, plus four audio outputs, two MIDI interfaces on standard DIN jacks and class-compliant USB. That it's user-assembled should in no way indicate the LXR is less capable than any factory-made piece.
The LXR has six voices, and it utilizes subtractive and FM synthesis to generate its sounds. The first three drum voices, with corresponding sequencer tracks, can make anything from kicks to small percussion blips via an oscillator with an envelope that modulates pitch. Following the oscillator is a filter that's switchable between six types, an amplifier, a variable waveshape distortion and a sample rate reducer, the last two being at the end of every voice's signal flow. At the amplifier there is an additional transient generator with 12 choices of short transients to add a sharp attack to the synthesized drum hit with a particular characteristic, like a rim shot, drip or snap, for example. The next voice is a snare, though it can also do claps. It's a combination of filtered noise, with a pitch envelope-modulated oscillator and a transient generator. Voice 5 is a cymbal/clap voice, a three-operator FM synth that meets the transient generator at the filter stage and proceeds as above. Voice 6 is a hi-hat that's sequenced on both track 6 (closed) and 7 (open) with different decay times. These decay times are the only difference in architecture from the above cymbal/clap voice. They all generate wonderful metallic FM sounds.
In Voice mode, there are seven pages of parameters that are used to shape sounds. When a voice is selected, its sequenced steps are shown via LEDs above the step buttons, while parameters appear on a green OLED display. Parameter values are controlled by four soft knobs and one push-encoder knob. While in Record mode, turning these knobs can write parameters to individual sequencer steps. The oscillator page handles tuning and waveform selection, which is followed by a simple attack/decay envelope with a slope parameter. Velocity modulation, FM and an LFO get their own pages as modulation sources. The transient generator is labelled Click, with its own page of parameters, and next is the filter with drive control. The final mixer page controls level, panning, output and sequencer track length, but it also has the final effects of sample rate reduction and soft clipping drive.
While in performance mode, the soft knobs give instant access to things useful for jamming and writing. First is a roll rate, which is the note value of a manual drum roll, very similar to the Note Repeat function on an MPC. These can be triggered for playback and also recording. Morph is used for morphing between the selected sound and any preset sounds on the SD card. I'm not sure if you'd change it on the fly, but it's in this mode that shuffle (or swing) is set. Also in performance mode, the eight-page buttons can be used as selectors for jumping between and chaining together patterns, collectively known as a pattern set. One of the more interesting features of the unit is its pattern generator, which is sort of an extension of the Performance mode. Here the four soft knobs are used to change pattern length, the amount of steps with notes on them, their position, and again the morphing feature and roll rate. These changes overwrite existing pattern data but are great for injecting some controlled randomness.
As complex as the device is, it wasn't too difficult to build. It took a full day—about ten to 12 hours—but the very thorough instructions were well-illustrated with photographs. There was only one part, labeled Inductance 10uH, which appeared very different in the kit than the instructions, but the user forums had the solution. The kit does not include a power supply, but most switchable universal AC adaptors can provide the needed 7.5 V. My main gripe with the build, and the unit in general, is the case. While attractive, the interlocking grey translucent acrylic kept falling apart no matter what I did. My only solution was to tape the unit together. It looks terrible, but it got the job done. Recently added to the shop is a metal enclosure, which I haven't seen in person but recommend as an alternative. I was also a little concerned that the buttons were going to fall off, considering that they are held in place with a small ball of adhesive putty; they have fortunately remained in place.
Most importantly, the LXR sounds great, with all sorts of synthesis and pattern programming possibilities. For example, each track can be a different length, which is great for polyrhythms, and the added pattern generator is an excellent feature. Furthermore, steps can be broken down into eight sub-steps for finer resolution. For those who really dig (and can understand) hacking a device, the code and schematics are available and open-source. And you better believe people are already doing interesting firmware updates that are available for free download. Even simpler is the ability to swap out the waveshapes on the SD card for totally new sounds. If the building is above your skill level, the user forums has recommended builders listed. Either way, this is powerful little drum synth worth checking out.
Ratings:
Cost: 3.0
Versatility: 3.5
Sound: 4.0
Ease of build: 2.8