Horror drone sounds in Absynth

Drone sounds are indelibly associated with the genre of horror movie that emerged in the 1970s. Classic scores such as Suspiria (1977) by Goblin, and John Carpenter's The Fog (1980) make use of eerie wordless choirs and brooding analogue synth basses.

As well as these classic synth elements, contemporary horror scores make use of drone sounds that could be described as "organic", bringing with them associations of metal, glass or liquid.

I want to demonstrate a simple technique for turning any percussive audio sample into an organic drone sound.

Percussion sounds make great source material for these sorts of drones, because they tend to contain a rich mix of noisy partials. Also, the way in which these partials decay can be used to give a drone a very organic shifting timbre.

I'm going to use the granular sample module feature of Absynth to manipulate my source material. I think that granular sampling is overlooked for one of the simpler tasks it can achieve - it is extremely useful for slowing down audio without introducing pitch-shift artefacts.

Here I have taken a sample of an orchestral bass drum and by modulating the sample start envelope with a gentle slope I can make the sample play at a slow speed. Continuously looping the sound produces a pleasingly organic sound, but the attack envelope of the sample still makes it recognisable as a bass drum.

BassDrumLoopOrig by pedalsteeldrummer

By manipulating the oscillator amp envelope, I can remove the percussive click of the attack portion of the sound.

Then, by increasing the channel gain as I move the sample start point through the source file, I can turn the percussive decay portion of the sound into a continous sustain.

Send the sound through a suitably cavernous reverb effect, and the result is a beautifully mysterious, rumbling drone sound. I particularly like how the subtle fall in pitch of the bass drum as it decays is transformed into an eerie moaning sound.

BassDrumDrone by pedalsteeldrummer

The beauty of this patch is that I can produce a whole variety of organic drone sounds by simply replacing the source sample with other percussion material. Below is a selection of alternative drone-like sounds. Enjoy!

AbsynthOrganicDrones by pedalsteeldrummer

Related links

• Absynth: http://www.native-instruments.com

Evolving pads in Logic Sculpture

Sculpture is the physical modelling synth that is shipped with Logic Pro. It was released with Logic Pro 7 way back in 2004 but I have to admit that I've not given it a lot of attention until recently.

The problem I find with synths that claim to be able to accurately model real-life acoustic sounds is that if you want those type of sounds it is much easier to use a sample library.

What's more, physical modelling is a very different approach to synthesis than subtractive or FM, and I find that a lot of trial and error is required to get a feel for how the different parameters affect the resulting sound.

Just recently Native Instruments released a new Reaktor ensemble called Prism which claims to be able to produce "organic soundscapes, percussive keys, flutes and bells". Although Prism is not strictly-speaking a physical modelling synth, it inspired me to revisit Sculpture and make the effort to get a better understanding of how it works.

I have discovered that by using the "morph pad" that Sculpture incorporates you can come up some very beautiful evolving pad-type sounds.

The concept behind the morph pad is actually very cool (same as the "remix pad" concept that has been adopted by Camel Audio's Alchemy synth). Once you have programmed your basic pad sound you use the morph pad (pictured) to store "snapshots" of up to 5 variations of your patch. You create variations of your patch either by manually moving the synth parameters to new positions, or by using a "randomise" function that is provided. To create a sense of movement in your pad sound you draw an envelope on the morph pad which slowly modulates the synth parameters - and therefore the resulting sound - between each patch variation.

The reason the morph pad works so well is because changing the parameters of your physical model even slightly can produce very unexpected results. To create a similar kind of movement in a subtractive synth would require modulating many parameters with many different LFOs and/or envelopes.

Sculpture's physical modelling architecture uses the concept of "objects" rather than oscillators as sound sources.

I find that the most useful object for creating pad sounds is the "blow" model, being able to produce a range of smooth metallic or glassy sounds, rather like a waterphone or bowed vibraphone.

The "bow" and "wide bow" objects seem to produce very noisy, scratchy sounds which sound to me fairly harsh and unpleasant, kind of like a beginner violinist!

Evolving pads in Logic Sculpture by pedalsteeldrummer

Related links

• Logic Sculpture: http://www.apple.com/logicstudio/logicpro/
• Reaktor Prism: http://www.native-instruments.com