The Legend of Sealed's Deep Synthesis

With a new Decent Sampler instrument just released, I thought I'd write something about the (sadly now defunct) website that inspired my crazy experiment: Sealed's Deep Synthesis.

The website, a mac.com page, was taken offline on June 30, 2012. A Wayback Machine-archived version lives here though:

https://web.archive.org/web/20110107122757/http://homepage.mac.com/synth_seal/html/

Sadly, although all of the pages (and most of the images) remain, nearly all of the site's MP3 demos are lost to time - and there were A LOT of demos. During a 10 year run, Sealed covered around 100 different synthesizers - mainly interesting digital & hybrid models.

As a young whippersnapper who knew only of Arranger Keyboards, the site was a revelation. It's where I learned about a world of exotic instruments; Casio's like the hybrid 4-osc HT-6000 & CTK-1000 IXA Sound Source, Korg's DW8000 & Wavestation, plus, inevitably, the synth my new product is based on: The Korg Audio Gallery AG-10.

You see, Sealed did much more than just document or review these synthesizers, they liked to dabble in SYSEX - writing Emagic Sound Diver panels for a number of them. Their adaptation of the Korg AG-10, a simple General MIDI sound module, involved sending erroneous SYSEX data to the instrument in order to create a variety of startling effects:

I found some hidden waveforms, using a new editor. A new interesting waveform modulation - I call it ILM (Interactive Loop Modulation) - is possible by using the hidden waves.

• Various bits of samples are played back at random. It sounds like digital noise made by 'Jam loops', circuit-bending, ring modulation, aliasing and OSC-to-OSC crosstalk.
• Sample start point and the pitch parameters add unexpected effects.

Sadly, the 12KB Sound Diver editor is one of the files lost to time, so I had to reverse engineer the unit's SYSEX map myself using MIDIOX and an old Windows 3.1 Editor. Still, I cracked it and I have Sealed to thank for setting me on that journey - I feel that my own work is in some way a continuation of Sealed's adventures of digital exploration.

When the site went down, our emails remained unanswered, so we may never hear from Sealed again. Wherever you are, I hope there are synths to play.

Posted by MagicalSynthAdventure an expert in synthesis technology from last Century and Amiga enthusiast.

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