Moog Music Inc. is proud to present Dr. Joseph Akins’ five part series on the fundamentals of synthesizer programming. Dr. Akins is an associate professor at Middle Tennessee State University and strives to teach his students a complete understanding of synthesizers and computers as tools for modern music production. In this five part series Dr. Akins uses a Voyager to teach the process through which a synthesizer’s sound is generated and the techniques needed to program your own sounds and sonic experiments. In part four of this five part series Dr. Akins gives an in depth lesson on the low frequency oscillator or LFO.
Voltage Influenced Low Frequency Oscillator
The-Pittsburgh Modular Voltage Influenced LFO is unique in the modular world. It is a strange, triangle based LFO that lives in an 8hp euro panel. The module offers two outputs, a triangle wave, and a variable waveform that shifts from a triangle to something that is almost not completely a square wave. The VILFO also includes a unique voltage influence circuit. The influence works differently than standard control voltage inputs, it allows the incoming CV to mingle with the LFO waveforms in interesting ways, creating unique modulations and patterns.
A typical Voltage controlled oscillator works by using a CV input to directly control the oscillation frequency. The more voltage sent to the CV input, the higher the frequency of the ocsillator. The lower the voltage, the lower the frequency of the oscillator. Voltage Influence works by using the CV input to attenuate the frequency of the oscillator while at the same time injecting some of the voltage from ICV Input to the feedback loop of the oscillator. Results can vary from subtle to chaotic. Subtle results can be similar to tremolo, shuffle, or soft reset while more extreme settings produce glitchy, rhythmic, chaotic fluctuations in the frequency of the VILFO. At the most extreme the VILFO can be stopped using Voltage Influence.
If you already bought the LFO 1.x, v2.0 will be FREE for you.
It will be available here: http://designthemedia.com/lfo
One year ago, it was the first efficient LFO officially supported (by us) for Ableton Live and it has a been liked & used by a lot of people.
With LFO 2.0, you can modulate each parameters of your liveset in real time.
You only have to drop it in a MIDI track, click on a button then click on the parameter you want to modulate and it works.
You can use built-in waveforms or even draw your custom one.
You can use the LFO 2.0 synced with the Live’s transport, or totally free by setting up the frequency.
– modulation of ALL parameters including tracks’ volume, panning & sends
– free or synced to transport
– classic waveforms (sine, ramp up, ramp down, saw, square, noise)
– custom waveform available with the whiteboard to draw it with your mouse
– presets & liveset friendly (all saved with liveset & presets)
– undo history safe
– LFO can control LFO to produce rich and complex modulations
– MIDI thru compliant (you can use it directly in your MIDI instrument track)
– GUI remixed
– all LFO2.0 parameters auto mappable to APC40
– Ableton Live 8.2.x
– Max for Live
– Design, concept, implementation : Julien Bayle
– New extensions sold by C74 & coded by Jeremy Bernstein
Boutique synthmaker Jomox introduced the Moonwind Analog Filter Tracker.
The Moonwind Analog Filter Tracker is a true analog stereo filter, with built-in step sequencer, an FX chip, 2 LFOs and envelope modulation. Everything is storable and controllable via MIDI.
Synthetic Sound Labs has just released its first Euro rack format module, the Model 2260 Modulation Orgy, further expanding its line of 5U format synthesizer modules. This new 16 HP width module contains a unique Low Frequency Oscillator (LFO) that offers unmatched modulation flexibility.
Synthetic Sound Labs has been in the analog synthesizer business since 1973, but the 2260 is the first Euro rack module and the sixth in SSL’s continuing line of new analog synthesizer modules.
LFOs are typically used by analog music synthesists in conjunction with other analog sound producing devices for creating slow, undulating rhythms and sound patterns. The SSL 2260 Modulation Orgy features both manual and external voltage control over LFO Tempo (speed), tempo Multiplier, Waveform and Waveform Distortion. A total of eight Waveforms are produced, including Sawtooth, Ramp, Rectangle, Triangle, Sine, Sweep, Lumps and Random. All these (except Random) may be modified using the Wave Distort controls to vary waveform duty cycles. Independent output jacks provide both normal and inverted LFO phases.
2260 ‘Modulation Orgy’ Specifications at a glance:
- Model 2260 Tap Tempo LFO
- Function: Flexible Low Frequency Oscillator (LFO)
- Tempo Adjust: .05 Hz to >50 Hz (approx)
- Tempo Multipliers: Six (0.5, 1, 1.5, 2, 3, 4; overlapping) – Manual & voltage controlled
- Waveforms: Saw, Ramp, Square, Triangle, Sine, Sweep, Lump and
- Random – Manual and Voltage controlled
- Wave Distortion: 10% to 90% (approx, except Random) – Manual and
- Voltage controlled Inputs
- Tempo CV, Multiplier CV, Waveform CV, Distort CV, Sync, Level CV. 0 to +5V nominal.
- 1/8” Phone jacks. 100k impedance.
- Outputs: Clock (0 to +5 digital), LFO voltage (10V P-P; +/-5V). 1K impedance.
- 1/8” Phone jacks.
- Panel Indicators: LFO Rate – Red LEDs
- Panel: High quality 0.062” aluminum. Durable black Metalphoto finish with
- natural aluminum and copper graphics. Complimentary Brass colored knobs.
- Power: Euro rack standard 16 pin keyed header.
- +5VDC @ 14ma, +15vdc @ 16ma, -15vdc 18ma
- Size: 5.0” H x ~3.25” W x ~1.25” D (16 HP). Skiff ready.
Modulation Orgy Details
A unique feature allows the 2260 to synchronize to precise multiples of the musical beat permitting timed vibratos, tremolos, and clocking of external sequencers and sample & hold type devices. Synchronization is accomplished by manually operating a front panel button, or supplying external clock pulses via the external Sync input. Multiple 2260s may also be cascaded to provide complex polyrhythmic modulation patterns, which is aided by use of the Clock output jack.
The basic LFO Tempo (frequency) is adjustable from approximately 0.05Hz (a 20 second cycle) and 12.8Hz. However, in conjunction with the Multiplier, this range is extended from 0.025Hz (a 40-second cycle) to over 50Hz in six overlapping tempo multiplication factors, ranging from 0.5 (1/2 note) to 4.0 (sixteenth note).
The external Level CV input responds linearly and is normalled internally to +5V so that with no input, the 2260 outputs are at maximum. This convenient input can frequently save a separate VCA when doing voltage controlled modulation depth.
A panel LED displays the LFO output rate. Knobs are conveniently placed for ample room for manual adjustment. Top quality 1/8” jacks permit smooth, effortless patching.
Quality, solder masked, fiberglass-epoxy printed circuit boards and meticulous hand-crafted assembly assure years of trouble-free service.
An introduction on how to use MidiShaper to modulate Apple Logic. See also http://www.cableguys.de/midi-shaper.html
MidiShaper brings Curve’s flexible yet powerful LFOs and envelopes to all your favorite synthesizers and effects.
Four LFOs and four envelope generators work together in a sophisticated modulations matrix that can be set up to output modulated pitch, modwheel, channel aftertouch or any MIDI control messages.
MidiShaper’s LFOs can run infinitely or be retriggered, synced to your host sequencer from a buzzy 1/128 to an expansive 32 bars, set to the played note, or run from 0.02 Hz up to the audible range and brain frequency. Like Curve, MidiShaper features completely editable waveforms for its LFOs.
If your plugin or host sequencer allows for MIDI control, you have a great tool at hand to create vivid, inspiring sounds and bring the flexibility of Curve to your favorite software plugins, hardware synthesizers, MIDI VJ tools, lighting consoles and 1980’s MIDI keyboards.
Here’s some background info on the project:
Further progress on a digital synth project that I plan to start producing very soon. The synth will be reprogrammable from any computer and the code can be easily bent or created from scratch. It also has an LFO controlled analog resonant lowpass filter to fatten up the sound (also circuit bendable) . This project will be COMPLETELY open source (schematics, code, everything) once I get everything organized.
The quadrature LFO is a special module that was not found on many modular synthesizers back in 1970s. Mostly, only companies like Polyfusion, Buchla or Serge would propose such a weird LFO.
Basically, it is a sinewave LFO with four outputs which are running at the same rate but are phase shifted by increment of 90°. That is, the first output has a shift of 0°, the second 90°, the third 180° and the fourth 270°. What is it useful for ? Mostly it is for modulating simultaneously up to four sources at the same rate but out of phase. This makes it possible to achieve so called “Barber pole” effects or “Shepard tones”. For example, imagine that you connect each output of the Quad-LFO to the V/oct input of four different VCOs, then you’ll hear continuous though steady (paradoxical, ain’t it !) rising and falling intermangled pitches (see ,).
It can be used also to drive four VC-panners to create rotating sound effects that fill the stereo space. The core of the circuit is based on the quadrature oscillator circuit of Ian Fritz’s ChaQuO chaos oscillator . I modified it in order to have voltage control of the frequency and also I added buffers with output LED indicators and a toggle switch that makes it possible to exchange the phase of the 90° and 270° signals in order to change the direction of the phase rotation. This simple trick is very handy when performing “barber pole” modulations. Each LED show the positive part of the corresponding signal, they are organized on a circle to visualize the phase differences between the signals.
In this video:
Music from my modular synthesizer.
Featuring the Yusynth Voltage Controlled Quadrature LFO module. The colored lights are on the module and the phosphor green “fireflies” are from my BK Precision 2120 oscilloscope. I tapped into the 90 deg and 180 deg outputs and switched them with a Q149 Signal Selector module then sent them on to the scope channel 1. Channel 2 picked up the 270 degree output. I then fiddled with ground, DC and AC readings as well as the divisions voltage readings on the scope.
Video edited and enhanced with Final Cut. Audio of three tracks mixed and mastered in Cubase 4.
A quick demonstration of Yves Usson’s Voltage Controlled Quadrature LFO.
In this video:
I sent each quadrant into a separate oscillator . The same voltage was split with a “Y” cable and sent to adjacent amplifiers. For instance, if the voltage from zero degree was sent to oscillator one then the same voltage was sent to amplifier two which had the 90 degree oscillator running through it. The voltage from 90 degrees was sent to oscillator two and the same voltage was sent to amplifier three, etc..
This made the quadrature become the delay envelope to the rising/falling portion of the next quadrant pitch only. When the “direction” switch was thrown, the pitch changed direction from rising to descending.
In this demo the voltage control (FM INPUT) was not used. This is a powerful feature which Yves built into the design.
British electronic music label Warp Records have recently been adding a large chunk of their back catalog to Spotify. Boards of Canada will be a welcome addition for many, but as a long-time fan of the label there are several other new additions from the Warp archive that I think are well worth checking out.
Here are but a few examples as recommended by Spotify:
Boards of Canada – Geogaddi
Edinburgh’s finest IDM band Boards of Canada finally arrive on Spotify, with both Twoism and Geogaddi now available. They’re sometimes a bit too ambient and IDM for my tastes, but they’re one of Warp’s biggest bands and a group who’s absence from Spotify was often lamented.
Broadcast – The Noise Made By People
Broadcast are one of my favourite bands and this is perhaps their finest album. Available now for the first time on Spotify, The Noise Made By People is psychedelic sixties electro that’s at turns ethereal, haunting, timeless and retro-futurist.
I was so sad to hear that lead singer Trish Keenan had died after catching swine flu a few months ago. Her voice was quite unique and I’ll never tire of listening to this album in particular: it means a lot to me.
Red Snapper – Reeled and Skinned
Warp band Red Snapper added jazz and other “real” instruments to the electronic mix of Warp’s mid-90s sound. I’m no fan of jazz but I loved Reeled and Skinned when it came out, with its dirty sax and intricate drumming. You could say I was hooked
The Sabres of Paradise – Haunted Dancehall
The Sabres of Paradise (and later Two Lone Swordsmen and The Aloof) were bands whose singles and albums I all eagerly bought back in the 1990s. The Sabresonic sound is dubbed-out dance music with a heavy dose of electro-experimentation; 1994′s Haunted Dancehall is probably their triptastic classic.
LFO – Frequencies (Stereoklang personal favorite)
The Low Frequency Oscillation kick-started the whole Warp success story, with the single LFO hitting the UK Top 20 back in 1990. It might sound a little dated in parts now, but just you wait for the forthcoming acid house and techno revivals…