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Given the lack of specific information available about imitone prime, its popularity during this campaign has been surprising -- it accounts for almost half the funding raised for the project! Today, I'll be addressing that informational gap as best I can.
First, its purpose: "imitone" is designed to be simple, accessible and powerful. Notice I don't call it "imitone basic" or "imitone lite". That's because it's my core product. For a majority of people, it will be everything they need and nothing they don't to bring their ideas to life. However, the technology offers a depth of possibilities that goes further than that, and a significant minority of users will be inclined to explore and utilize those. imitone prime is designed with professionals, performers and tinkerers in mind: The proverbial toolbox to imitone's swiss army knife.
This article will get somewhat technical from here on in -- imitone prime is an advanced piece of software, with many esoteric features. So! Let's examine each in detail:
"Timbre" is an umbrella term for all the features of a sound aside from its pitch and intensity. These are typically difficult to quantify and easy to qualify: The difference between an "aah" and an "ooh" is easy to recognize, but hard to express in mathematical terms.
Thus far I have implemented one timbre metric in imitome prime: brightness, meaning the "harshness" or "openness" of a sound for a given pitch. As a general rule, "hmmm" is a dark sound and "aah" is a bright sound. Your throat produces a bright sound -- aah -- when you vocalize, and your mouth and lips filter that sound and darken it based on their shape. Nasal, gritty or harsh vocal sounds are naturally brighter than others.
prime's brightness control lets you map this metric (the tone's "spectral centroid") to a MIDI message of your choice. By default, it outputs to CC74, which most often controls a filter on the receiving synth. By shifting your voice between vowel sounds, you can control this filter as you sing.
A quick demonstration:
Many other timbre metrics are possible, and if I should have any good ideas you can expect to see them in prime. I'm currently contemplating a harmonicity control -- it would measure transitions between "breathy" and "clear" sounds, which could be used as a dry/wet fader. Since harmonicity is used to select notes, such a controller might continue to change even when no note is active.
MIDI allows for transmission on up to 16 channels. Whereas imitone is designed to control a single instrument, prime will be able to control up to 16 per output device, with each of these mapped to a different audio input.
Each active channel is set to a "mode" -- tone or beat. Each may have different settings for its detection and MIDI sequencing, as described in "advanced configuration" below. Sharing a single audio input between channels will be supported.
A few examples: You might have a single microphone set to detect tones on channel 1 and beats on channel 2, with the intention of alternately humming and beat-boxing. Or you might get a few friends together and use several microphones, each controlling a different instrument, to form a string quartet or a ska band. (This can be done as a performance if you use contact microphones.)
imitone prime will offer many, many more adjustable settings than imitone, most of which will be individually manipulable for each MIDI output channel. These break down into two categories:
Sequencing settings build on the switches offered in imitone. You will be able to configure its continuous controls (expression, vibrato and brightness) to different CC numbers or aftertouch controls. CCs may be coarse or fine, and aftertouch may be monophonic or polyphonic (in which case controls may be sent separately for each note). Pitch bend and glide will be somewhat more customizable, permitting a choice between various legato / portamento methods and the adjustment of the pitch-bend range.
A feature which has been requested several times is the ability to turn off certain MIDI features -- for instance, to turn off musical notes and use imitone exclusively as a way to control expression and vibrato while playing a conventional keyboard. I have decided to add support for this, and will likely add further settings based on user suggestions.
Analysis settings allow fine-tuning of imitone's internal algorithms, allowing them to be "tweaked" for certain uses. These include detection range, tuning scheme, resonator cell parameters, and harmonicity thresholds for note selection. Higher-level algorithms like vibrato stabilization will also be adjustable.
Some settings (in both categories) may need to be configured by editing a text-file, especially in early and beta versions of imitone prime. It will be possible to save and load configurations per-channel.
imitone prime will have an experimental "poly mode" where it will be capable of detecting more than one note simultaneously from a single input. This means you could have multiple people harmonizing into one microphone, or detect a double-stop on a string instrument.
While my technology lends itself well to this problem, it's a notoriously difficult one to solve well (especially for larger numbers of notes) and I need to do more research before I can make claims about its effectiveness.
This feature was originally designed to enable performance with imitone as part of a live band. It requires two microphones -- a signal and a reference. The signal mic is placed near the tone source and the reference mic is placed in the environment where it gets similar levels of ambient sound but much less of the controlling voice. By comparing the two, the desired tone can be isolated.
However, since beginning work on this feature, I learned about a much more efficient alternative: the throat microphone. Wearable on the neck and costing as little as $15, this device isolates far better than any algorithm and requires less set-up and equipment to use. For this reason, I'm considering cancelling this feature or otherwise making it a very low priority. Let me know what you think in the comments.
While working on this technology, I've developed various charts and graphs to give me insight into its internal algorithms and processes as they operate on my voice. Removing these from imitone for the sake of simplicity was the right choice, but I was a little heartbroken about it. I plan to sneak my favorites back into imitone prime as helpful displays -- but not before letting imitone's designer Richard give them a face-lift.
Waveform (below left) lets you see the wave-shape of your voice, which holds stable for any given sound and changes as you alter your timbre, pitch or loudness. This information is used to compute brightness and harmonicity.
Fourier (above right) shows you an FFT spectrum of the waveform, letting you view the distribution of your overtones. Yes, I know I was laying the hate on FFTs last week, but remember my remark: The fourier transform takes a cyclic signal, and a periodic waveform is one. Furthermore, I still don't use any transforms in the actual detection algorithms -- this is just a handy way to examine the data. For instance, the sound above is throat singing, which produces a characteristic "lump" of overtones high in the spectrum.
Lastly, the spectrum is close to my heart. This colorful artifact offers an insight into the core logic of imitone, evolving in tandem with the technology. I can't really tell you what it will look like, because the data will continue to change. But darn if it isn't a mesmerizing thing -- especially in motion.
And that's imitone prime in a nutshell. At least, as far as I've planned -- I might make additional features or discoveries that find their way in. Perhaps I've convinced you that you need it, or that you don't need it! In any case, I hope you come away from this feeling a bit more informed in your pledge decision. imitone prime's final cost will likely be around $99, and the $60 pledge level includes both versions of the program.
That's all for now --