This unusual audio effect has been growing in popularity over the last decade, It splits incoming audio into any number of frequency bands, then applies a modulating filter delay to each band.

While Native Instruments has its own version of Spectral Delay, there are many different ways to implement the effect.Shpongle andNBC's Kings both put the Yofiel version to amazing use, as demoed on this page. But if you are a professional, you might want to consider getting the Native Instruments version as well. If you already have Reaktor, this version is a little cheaper.


For this spectral delay, multiple Low Frequency Oscillators (LFOs) can modulate the delay, overdrive, feedback, and pan across the spectrum by diffrerent amounts for each band. The Frequency, symmetry, and phase of the LFOs can also be set to different amounts for each band. The number of bands and the band separation is selectable. There are multiple versions of the effect to provide low CPU utilization or more control. There are also mono and stereo versions.

Some Examples


This psychedelic band was one of my first fans. You can hear the effect in this video.The effect starts at 4:49.and is chopped in and out for the remainder of the song on the voice and drum tracks.

'Kings' TV Series

This TV show made extensive use of this effect. Here it is audible in the promo trailer starting at 1:00.

Spectral Flanging and Drum FX Demo

The ensemble includes a preset for modulation parameters for creating mobile comb-like striations in a string sound. 'Kings' also used this preset directly for expanding the strings in its opening sequence, While I can't include that video clip here for copyright reasons, I can provide a demo of the instrument directly. The sound instrument is Hume4, one of the other Metamusic instruments. Of course, Nietzsche Spectral Delay can be applied as a plugin to any instrument. Nietzsche Spectral Delay is also superb for overlaying unusual disco scratch and sound effects on rhythms.

So initially, his is a rough demo, as I need to get a new screen video recorder. My current one introduces ovder a second audio latency, so the audio sync is off by several bars. That aside, this video starts by opening the ensemble with Hume synth as source and demonstrates spectral flanging first. You will notice the flanging fading in and out after changing the effect's MIX slider on the on the instrument's right side. Then this video shows a few other effects, including spectral pan with LFO modulation, which is really striking. Then it opens spectral delay with a drum synth. You'll see lots of strange and amazing possibilities, especially with synced LFO. It concludes by showing the spectral delay instrument in an otherwise empty ensemble, ready for you to play with. Due to online bandwidth limitations, some of the subtleties are lost, but I overdid the effect in places to make it more obvious.

. , as shown in this extended example. The effect is first played dry, then various presets applied.

Some Details

There are various clever ways to modulate the signal and delays and other characteristics separately for each band. The single poly-display unit changes view to show different parameters changing across all the bands, depending which you wish to tweak.

This just describes a few controls. Usage is rather intuitive once you have your hands on the knobs, so I hadn't written it all up, but I do plan to do so with various tips on different possibilities.


All the knobs labeled SPECTRAL adjust the parameter across the filter delay bank--you can adjust +/- values to linearly scale the parameter up or down the bank of filter delays just by moving one knob. This creates unique raking and warbling effects. Try the spectral delay knob first, it should be obvious after that.


All the GROUPING knobs quantize the fixed spectral delay values into sets. You can then move the sets up and up and down the filter delay bank with the "rotate" knob. This is an excellent effect for live performance.This is just a few of the things it does. The instrument is rather intuitive, so I hadn't written it all up, but I plan to do so with some usage tips.

Spectral LFO

The SPECTRAL LFO can also provide varying amplitude up and down the spectral bands. If you adjust its parameters and you will see many types of modulation possibilities.

Resonance Modulation

Additionally there is Q MODULATION for the filters; and on the output.

Band EQ and Limiting a 4-band Equalizer and 4-band Limiter provides individual frequency-range adjustment limiting on each band output. Because spectral delays isolate and enhance individual bands, the harmonic spread can become centered in a particular region. The output section allows balancing across the spectra, or enhancing of a particular spectral zone, and also of course, saving of the EQ curve with the snapshot.

Adjustable Taps

You can change the number of frequency taps by changing the instrument's number of voices. By default it's set to 32 voices. The processor utilization moderately increases for each additional band. I have been able to use the effect on a 1.6GHz Pentium with 100 voices.

Built-In Demos

The ensemble arrives hooked up to a drum sequencer for demo. (Turn on the Reaktor clock after opening the ensemble for instant gratification.) After the snaps, the easiest way to make sense of it is to turn the LFO amplitude to 0 and twiddle the DELAY knobs. (The GROUP and ROTATE only have effect ifSpectral value is not zero).

It sounds great with Carbon. Carbon2's default patches play with >100 voices on a 2.66ghz P4 and Windows XP.

Download and Support


Nietzsche Spectral Delay (Reaktor 5.1+)

Cost: $20.00

Yofiel Software Support

I prefer to see problems myself on your machine, for which I use Skype, because it is on all platforms and supports screen sharing, audio, video, and text messages.For all support inquiries, please make sure you haveregistered on my site first, thenContact Us with your Skype username.

Obtaining Skype: If you do not have Skype, please install it before contacting me. It is available for all devices on theSkype download page.

Thank you for your interest in Yofiel's metamusic. I hope you enjoy our software.

-Ernest Leonardo Meyer