Category: Music & Synthesisers

Categories
Modular synthesisers Music & Synthesisers Stuff I made

Jam of the day: Not your dad’s vocoder

The Mutable Instruments Clouds is one of the most popular Eurorack modules ever. It was intended to be a “texture synthesiser”, an instrument which uses granular synthesis in order to extract a texture from an incoming signal.

Granular synthesis is just the “default” mode, however. There’s other ways of extracting texture from sounds and sure enough, buried on secret firmware number 4 is a happy little phase vocoder! Rather than explaining how it does what it does, take my word for it that it can smear any dynamic sound into a static timbre using complicated maths which gives engineering students lifelong PTSD. I was using this trick to create drones back in 1999 by “misusing” the noise removal feature of Cool Edit Pro.

Anyway – sound goes in, drones or whooshes or wibbly noises or crackles come out. Here’s what it sounds like.

There is no actual synthesiser in this recording aside from Clouds – I played a D5 chord in on the electric mandola (2200 if anyone’s keeping score) and froze the timbre in place to create the drone. Then I played in some other notes live over the top. Add a bit of delay to smooth it out and that’s all there is to it!

Despite its popularity, the designer of Clouds discontinued it earlier this month, citing disappointment that “feedback and reverb got stuck to the maximum setting, resulting in a never-decaying smudgy howl of hype”. This is part of the reason I avoided it for so long, because I didn’t want to.

Categories
Modular synthesisers Music & Synthesisers Stuff I made

Patch of the day: Wire speaks to wire

Reverb is an electronic effect which gives any sound signal the illusion of reverberation. Spring reverb does it by electromechanically vibrating one end of a set of springs in a tank, then recording the vibrating strings to create a pleasantly “wet” metallic ringing.

Behold my happy little Belton spring reverb tank, ready to be patted soothingly.

This short ambient piece was made using a spring reverb effect, but it’s not actually reverberating anything except itself. I sent its output back into the input to create a feedback loop. This made the springs ring uncontrollably after a few seconds, but I can mute the springs with my fingers to quieten them down.

There’s been a bit of reverb and delay added afterwards to space it up a bit. 🙂

Categories
Modular synthesisers Music & Synthesisers Stuff I made

Jam of the day: Brainburner (excerpt)

 

This is a jam for anyone who enjoyed the harder house tracks like Rollin’ and Scratchin’ or Rock’n Roll on Daft Punk’s album Homework. It’s a spiky glitchy drone with some nice polyrhythmic percussion and that’s it – maybe not everyone’s cup of tea but I like it. 🙂

Tech notes

I used two of my new modules for this! The Music Thing Modular Pulses mk 2 is outputting a randomly generated six note rhythm tapped at two points for the clap and the hi-hat. The modulation state of the drone is being sample-and-holded in sync with a Euclidean rhythm out of the Little Nerd. The drone is feeding into the Voltage Control Lab VCF-74 Mk 1 where it’s being frequency modulated; that’s fed into a Ladik Waveform Animator then on to the Eowave Fluctuations Magnetiques filter bank through a parallel low-pass and band-pass filter.

The drone is just sitting at one steady note. So why does it sound so lively? The experiment was to see what would happen if I put a pulse wave through a low pass filter and then put that through the waveform animator. The animator only works on waves with gradual transitions which means a pulse wave goes in and out unchanged, but a low pass filter can introduce those transitions into the pulse wave by filtering the sharper frequencies away to make it transition more like a sine wave. The texture of the drone comes from crazy chaotic interactions between the filter frequency modulation, the waveform animator and the pulsewidth of the original oscillator.

Categories
Modular synthesisers Music & Synthesisers

Friday night jam session, 6 October 2017

I bought a couple of new Eurorack modules recently and wanted to try them out. Here’s the Chronoblob rippling an arpeggio across the fabric of spacetime with the help of the Deflector Shield in the aux path. Press play to travel through outer space or download here.

 

Categories
Modular synthesisers Music & Synthesisers

Patch of the day – Augmented vocoder

 

I got an Expert Sleepers Disting Mk 4 module on Friday. It is Eurorack’s designated swiss army chainsaw. Amongst its 76 modes, it can be a vocoder. I took it for a spin with a John Cage lecture as the modulator signal on Friday evening and the above is what came out.

Analogue and analogue-style vocoders are a system of band-pass filters, envelope followers and amplification. Two signals enter the vocoder: a carrier signal which supplies the timbre of the output sound, and a modulator signal which supplies frequency and amplitude information.

A bank of band-pass filters cut each signal into strips of frequency (think bass and treble, but much more precise). The vocoder tracks how loud the modulator signal is at each strip, then adjusts the volume of the carrier’s strips to follow the modulator’s strips. The carrier’s strips are combined back together as a whole signal and out comes Cylons.

One of the challenges with vocoders is getting output that’s as intelligible as the input. The intelligibility of the Mk 4’s vocoder was not great, so I mixed in a filtered version of the original speech. The filter is tuned to sibilant sounds (like s, f and th) which were getting lost in the vocoder process. It’s an old trick – the EMS Vocoder used for the Cylons has a cleverer version which lets sibilance through as it’s required – but a dumb version works in a pinch and as a result you can understand Mr Cage just fine.

For further fun, I’m modulating the pitch of the carrier signal with a random signal. This makes Mr Cage sound much more floaty than usual as the carrier floats up and down in pitch, giving him a rather more vague delivery.