

Assimil8or Software v2.03 has been released. Check the Downloads tab for details. Designed to provide a powerful, flexible sampling engine for modular synthesis, the ASSIMIL8OR Multi-Timbral Phase Modulation Sampler module is the latest incarnation of Dave Rossum’s decades-long pioneering of affordable professional sampling technology. ASSIMIL8OR provides eight independent channels of sampling with sound quality that can range from extremely hi-fi to low fi, all with extensive real-time CV control. Key ASSIMIL8OR features include: Eight-channel multi-timbral operation. Each channel will be available from its own independent output as well as appearing in the stereo mix output.

Superb 24-bit A/D and D/A conversion.

Mono or stereo sampling. Channels can be configured as eight mono voices, four stereo voices, or any combination. (Well, any combination that adds up to eight).

The ability to assign up to 8 samples to each channel and select between them in real time via CV.

DC coupling through the signal path for sampling of control voltages.

Unique timbral capabilities with the ability to phase modulate samples by external analog signals or by other samples (a first, we believe).

Variable sample fidelity with independently selectable sample rate and bit depth.

Real-time CV control of bit depth.

Real-time CV control of aliasing (from virtually none to lots).

Extensive sample manipulation and looping capabilities.

Sample scrubbing under CV control.

One-shot or gated sample playback with variable attack and release times.

Gate/trigger inputs and CV inputs for each sample that can be assigned independently for each channel to virtually any sample parameter. Examples include:Pitch

Level

Bit Depth

Phase Modulation

Pan

Scrub

Sample Start

Sample Length

Loop Start

Loop Length

Release Time

Level Bit Depth Phase Modulation Pan Scrub Sample Start Sample Length Loop Start Loop Length Release Time A front panel accessible SD card for sample and preset storage.

And a lot more… ASSIMIL8OR is available now from Rossum Electro-Music dealers worldwide.

Assimil8or Specifications SAMPLE MEMORY 2,300 seconds at 48kHz mono, freely allocatable between the 8 channels SAMPLE RATES 48kHZ, 96kHZ, 192kHZ A/D & D/A 24 Bits INTERNAL PROCESSING 32 Bits LATENCY 100 microseconds at the Mix Outputs 180 microseconds at the Individual Outputs INPUTS Sample L/R 2x 3.5mm mono socket 100kΩ Input Impedance Gate/Trigger 1-8 8x 3.5mm mono socket 100kΩ Input Impedance 1.6V threshold Control Voltage A 1-8 8x 3.5mm mono socket 100kΩ Input Impedance 96 kHz sample rate Anti-alias filtered to 20kHz bandwidth Control Voltage B&C 1-8 16x 3.5mm mono socket 100kΩ Input Impedance 48 kHz sample rate No anti-alias filtering OUTPUTS Mix Outputs L/R 2x 3.5mm mono socket 1kΩ Impedance Individual Outputs 8x 3.5mm mono socket 1kΩ Impedance POWER REQUIREMENTS +/-12V via 16-pin, Doepfer-style connector CURRENT DRAW

220mA +12V, 30mA -12V DIMENSIONS

28HP (W); Panel to power connector (with connector plugged in) 25mm (D) SUPPLIED ACCESSORIES 1x Micro SD card

1x 16-pin, Doepfer-style cable

4x M3 screws

4x M2.5 screws

4x Nylon washers

1x Quickstart Guide

Assimil8or Introduction and Overview An Assimil8or introduction and feature overview by sound designer Mike Kiraly for the Sonic Scenarios Video Series for Control. Assimil8or 2.0 New Feature Demos

Dave’s Introduction to Phase Modulation Phase modulation is a new kind of audio cross-modulation for sampled sounds. It can produce rich and varied timbres and textures, as well as wild distortions and grating noises. The word “new” is probably not accurate. Modular synthesizers have used frequency modulation (FM) since their inception. Low frequency FM produces nice vibrato effects, and audio rate FM creates interesting timbres. But exponential FM alters the perceived fundamental frequency of an oscillator; linear FM is required to alter the timbre while staying on pitch. When we use FM, we call the source of the modulation the modulator, and the oscillator being modulated is called the carrier. In the early 1970’s, John Chowning discovered using digital oscillators that linear FM through the zero point (so the carrier actually reversed its oscillation) produced very diverse and pleasing timbres. Yamaha further developed this technology, but while Yamaha continued to call their implementation “FM”, they actually were using Phase Modulation. Also worthy of note, Don Buchla heard Chowning say that you couldn’t do “through zero” FM with an analog circuit, so Don did just that with his Music Easel’s Complex Oscillator. Let’s look at some oscilloscope photos to understand the difference. If I frequency modulate a sine wave with another sine wave, the ‘scope shows us the effect on the waveform. (The modulator is on the bottom in blue, the carrier in yellow on the top): Now let’s use a pulse waveform to modulate a sawtooth wave carrier: Here you can see that when the pulse is high, the sawtooth gets steep, when it’s low, the sawtooth slope is slight. Now let’s use “through zero” modulation and turn up the gain of the modulator to show how the sawtooth slope now goes downward (backward) when the FM goes negative: Now, a big problem with through zero linear FM is that as the pitch of the modulator goes up, it has less effect on the carrier’s timbre. Here’s the same setup as above, but with the frequency of the modulating pulse wave increased by 1.5 octaves. Note that the carrier waveform is getting to be pretty much an ordinary sawtooth. The solution, as Yamaha discovered, was to instead of modulating the carrier’s frequency, have the modulating oscillator modulate its “phase.” What this means is that the modulator is directly changing the location in the carrier’s waveform, rather than changing the rate that the carrier oscillates by moving along through its waveform. Here’s what a sawtooth phase modulated by a pulse looks like. When the pulse goes high, the carrier skips ahead to a higher point in the sawtooth ramp; when it goes low, it skips back to a lower point. But now when we increase the modulator’s frequency, the carrier is still dramatically affected. And we can see also in this waveform cases where the pulse has skipped backwards or forwards over the sawtooth’s edge, creating more large edges at this point. We can modulate the sawtooth with a sine wave too. Here, you can see how phase modulation maintains the character of each waveform, giving a new timbre with the characteristics of both the modulator and the unmodulated carrier: As a final example, here’s the waveform that results when a sawtooth is modulated by a violin sample. The frequency and sharp edges of the sawtooth are maintained, but the complex timbre of the violin is added: When first planning Assimil8or, I thought phase modulation might be a neat feature. I was really surprised to find almost nobody had taken advantage of phase modulated sampled sounds. My first few experiments were really exciting, and I hope you have fun exploring this capability of Assimil8or.