 CYLONIX 18 Channel Vocoder Help Index

Overview

Introduction

Registration

Vocoder Controls

Spectrum Modifiers

Spectrum Display

Input Mode

Play/Record

Carrier/Modulator Source Selection

Filter Bandwidth

Channel Pan Controls

Channel Level Controls

Gain Control

Mix Control

Sibilance Control

Saving/Loading Your Settings


Spectrum Modifiers

As described in the introduction the vocoder computes the energy of the modulator signal in each of 18 separate frequency bands. These energy measures are then used to modulate the level of the carrier signal in the same 18 frequency bands.

Usually the mapping of analyzer frequency bands to synthesizer frequency bands is the trivial mapping where the energy of the lowest frequency analyzer section filter output is used to modulate the output of the lowest frequency synthesizer section filter, the energy of the next highest frequency analyzer filter output modulates the next highest frequency synthesizer filter output and so on, as illustrated below:

ANALYZER SECTION FILTER                         SYNTHESIZER SECTION FILTER

                      1                                   ------------>                               1

                      2                                   ------------>                               2

                      3                                   ------------>                               3

                                                               .

                                                               .

                                                               .

                    18                                   ------------>                             18

                                 The Normal Spectrum Mapping

Spectrum Shifts

Some interesting effects can be obtained if we alter the mapping of analyzer to synthesizer filters from the normal case given above.

A simple spectrum modification is to shift the synthesizer frequency bands relative to the analyzer frequency bands. For example, we can shift the spectrum up by 1/3 of an octave with

the following mapping.

ANALYZER SECTION FILTER                         SYNTHESIZER SECTION FILTER

                    NONE                           ------------>                               1

                      1                                   ------------>                               2

                      2                                   ------------>                               3

                                                               .

                                                               .

                                                               .

                    17                                   ------------>                             18

                                 A Spectrum Shift of 1/3 Octave (one filter width)

There are six buttons on the vocoder display that can be used to set the amount of spectrum shift. These are:

-2    -1     0     1      2      3

Only one of these buttons can be on at one time (e.g. the -1 button in the situtation depicted above).

Pressing one of these buttons will result in the application of the associated spectrum shift. A shift of 0 implies the normal spectrum mapping. A negative shift indicates that the analyzer section filter energies modulate synthesizer section filters of lower frequency, while a positive shift indicates that the analyzer filters are mapped to synthesizer filters of higher frequencies. In the case of a negative spectrum shift of N filter widths, the N highest frequency synthesizer section filters will not be modulated (their output will be zero). This is because there are no analyzer filters of high enough frequency to provide the modulation signals. Likewise, in the case of a positive spectrum shift of N filter widths, the N lowest frequency synthesizer section filters will not be modulated

In general, positive spectrum shifts cause the resulting vocoded speech to sound more female, and more "Donald-Duck-ey", while negative spectrum shifts resulting in more male sounding and muffled speech.

Spectrum Inversion

An interesting effect can be obtained by inverting the mapping between the analyzer and synthesizer sections. That is, the highest frequency analyzer section filter energy is used to modulate the the lowest frequency synthesizer section filter, the next highest frequency analyzer section filter energy is used to modulate the next lowest frequency synthesizer channel and so on, as shown in the following figure:

ANALYZER SECTION FILTER                         SYNTHESIZER SECTION FILTER

                      1                                   ------------>                               18

                      2                                   ------------>                               17

                      3                                   ------------>                               16

                                                               .

                                                               .

                                                               .

                    18                                   ------------>                              1

The spectrum is inverted when the   INV [image]    button is pressed. Please note that any spectrum shifts will be applied after this inversion process. The sound that results from spectrum inversion is usually quite unintelligible (but interesting). The vocoder sometime distorts when in this mode; if this happens reduce the setting of the gain slider.

Random Spectrum Mapping

Another interesting spectrum modification is a random scrambling of the analyzer-synthesizer mapping. This can be obtained by pressing the  Rand [image]  button. Doing so creates a randomization of the mapping. The scrambling is such that no two analyzer outputs are connected to the same synthesizer control input. Each time the Rand button is pressed a different scrambling pattern is generated. If you find a pattern that you like you should save it using the SSet button (Save Settings).

Linear Spectrum Mapping

Pressing the LIN [image] button sets the spectrum mapping to the normal mapping of each analyzer section to the corresponding synthesizer section of the same frequency band.

Spectrum Mapping Display

Pressing the TDisp [image] button toggles the display between the Modulator Spectrum level display and the Spectrum Mapping Display. The Spectrum Map shows a matrix of channel map indicators. Each column of the matrix corresponds to a synthesizer channel, while each row corresponds to an analyzer channel. When the Spectrum Map is displayed, the user can adjust the mapping by moving the map indicators with the mouse. To do this, click, with the left mouse button, on the channel column whose mapping you want to change. The map indicator for this channel will turn red. Hold down the left mouse button and move the cursor up or down until the indicator is at the desired location.

Note: Adjusting the spectrum mapping with the mouse is not supported in the demonstration of the program.

Spectrum Sampling and Holding

Pressing the   Hold [image]    button will sample the analyzer control signals at the moment of the button press and will hold these values fixed until the Hold button is pressed again.

Pressing the    S/H [image]    button will periodically sample the analyzer control signals and hold them

until the next sampling instant. The rate at which the analyzer output is sampled is set by the RATE slider.

Using the Vocoder as an Equalizer

The vocoder can also be used in an Equalizer mode, by pressing the   EQ [image]    button. When this

button is pressed the analyzer control signals are all set to the same constant value, independent of the modulation signal. The synthesizer spectrum can then be shaped by using the channel level sliders, resulting in an 18 channel equalizer!.


Input Mode

There are two inputs to the vocoder, the carrier signal and the modulator signal. These can be generated internally (see Carrier Source Selection and the Play/Recordsections) or provided by inputs to the sound card's analog-to-digital converter (ADC). The input to the sound card's ADC is usually formed by mixing together a number of sources connected to the sound card, such as the microphone input, the line input, and the CD audio input. The relative level of each of these inputs can be adjusted with a mixer program supplied with the sound card. The ADC of most sound cards is stereo (the program will not work unless the sound card is stereo), providing two possible monophonic signal inputs. The vocoder program will use these two channels to provide the external carrier and modulator signal sources. For example, the left line input could supply the carrier signal and the right line input could supply the modulator signal. A common usage of the vocoder would be to use the sound card microphone input to provide the modulator signal. Unfortunately, on sound cards like the Creative Labs Sound Blaster, the microphone input is monophonic and is spread equally over the two stereo channels. To handle this case, the vocoder program assumes that one of the channels (say the left) contains the carrier signal as well as its portion of the microphone signal. The other channel (say the right) just contains the microphone signal. The carrier signal is then obtained by subtracting the right channel from the left (thereby cancelling out the microphone component). The modulator signal is obtained directly from the channel (in this case the right) which contains only the microphone signal.

There are four different inputs modes which determine how the input channels are assigned to the carrier and modulator signals. These are selected with the following set of buttons:

L/R   R/L   M/L  M/R

Note that only one of these buttons is on at a time. The first letter in the button label indicates to the channel used to provide the modulator signal. The second letter indicates the channel used to provide the carrier signal. That is,

L/R indicates that the modulator signal is provided by the left channel, the carrier comes from the right channel.

R/L indicates that the modulator signal is provided by the right channel, the carrier comes from the left channel.

M/L indicates that the modulator signal is taken from the right channel and the carrier is derived from the difference between the left channel and the right channel. In this situation the modulator would be a monophonic signal, such as the microphone input, and the carrier would be connected to the left input.

M/R indicates that the modulator signal is taken from the left channel and the carrier is derived from the difference between the right channel and the left channel. In this situation the modulator would be a monophonic signal, such as the microphone input, and the carrier would be connected to the right input.

It is crucial that you understand how to use the Mixer program supplied with your sound card! Review the mixer documentation.  For example, in the Creative Labs  "Creative Mixer" program the inputs to the sound card ADC are enabled by selecting the "Recording Controls" and clicking on the "XXX Input Recording Source" box, where "XXX" is one of "MIDI", "CD", "Line", or "Mic". These boxes have a little microphone icon. Set the recording level sliders for the inputs you are interested in to as high a level as possible without causing the vocoder to distort. In the "Volume Controls" settings of the mixer you will want to mute all outputs except for the "Wave Ouput".

Due to limitations in the Creative Labs sound blaster full duplex implementation, external inputs to the vocoder are digitized to only 8 bit precision. The vocoder output is digitized to a 16 bit precision. 16 bit wav files can be loaded and used as input to the vocoder, however.

You will note that there is about a half second delay between the input and output. This is an unavoidable consequence of the Windows operating system, and is NOT removed in the registered version of the program. Sorry! This delay reduces the usability of the vocoder in live settings (except in the hands of skilled practitioners!) but should not affect its use for generation of wav files, and for just plain goofing around.

It is strongly recommended that you install the latest full duplex drivers from your sound-card manufacturer. These are usually available from the manufacturers web page. For example, the Creative Labs web site (for SoundBlaster cards) is www.creaf.com.


Play/Record

One of the primary intended uses of the vocoder program is to generate wav files of vocoded speech. These can be then put to many different uses, such as in MOD files, or as sound effects in games or merely as sounds associated with various Windows events.

Recording and saving a snippet of vocoder sound to a wav file is very straightforward. To begin, press the REC button. This will begin the recording process. Then create your sound, and press the REC button when you are done. Please be aware that whenever the REC light is on, sound data is being put into an ever growing memory buffer in your computer's RAM, and at some point you will run out of room. At this point the recording process should stop (but the record light will stay on) and your computer just might get hung up.

REC    Play    Save

Once you have recorded your sound bite, you can audition it by pressing the Play button. This will merely play back what is stored in the record buffer. During this playback the normal vocoding process will be suspended. If you press Play while recording, recording will be terminated.

Once you are satisfied with your sound bite, it can be saved by pressing the Save button. This will bring up a file dialog which will prompt you for the name of a file to save the sound in. The sound is saved as a stereo, 16 bit, 11.025 KHz format wav file.

You can now use other programs such as CoolEdit and SoundForge to process your sound even more!

NOTE: The save function is not available in the demo version!


Carrier/Modulator Source Selection

The carrier input to the analyzer section can come from a variety of sources. These sources are selected with the following five buttons:

Extrn    Pulse  Chor1   Chor2  Noise

If the Extrn button is on, the carrier input is taken from the sound card Analog-to-Digital converter (ADC). See the Input Mode section for details on how to determine the external input source.

If the Pulse button is on, an internally generated pulse wave is used as the carrier signal. This pulse signal has a duty cycle (ratio of on time to off time) of 1/4. The frequency of the pulse waveform is set by the FREQ slider.

If the Chor1 button is on, three internally generated pulse waves are mixed together to form the carrier signal. These three waves form a diminished chord (e.g. C-Eb-Gb). The frequency of the pulse waveforms are set by the FREQ slider.

If the Chor2 button is on, three internally generated pulse waves are mixed together to form the carrier signal. These three waves form a major chord (e.g. C-E-G). The frequency of the pulse waveforms are set by the FREQ slider.

If the Noise button is on an internally generated uniformly distributed white noise signal is used as the carrier signal.

Only one these 5 buttons can be on at one time.

It is also possible to read in a wav file and use it as either the carrier or modulator signal.

 LCar   PCar     RptC    LMod    PMod   RptM

Press the LCar button to select a wav file which will be read in and be available for use as the carrier signal. Once this file has been read in, you can press PCar to play the wav file as the carrier signal. If the RptC button is turned off, pressing the PCar button will play the wav file through once. If the RptC button is on, pressing the PCar button will play the wav file repeatedly. Turning the RptC button off again will terminate the carrier wav playback at the end of the current cycle.

Similarly, you can press the LMod button to select a wav file which will be read in and be available for use as the modulator signal. Once this file has been read in, you can press PMod to play the wav file as the modulator signal. If the RptM button is turned off, pressing the PMod button will play the wav file through once, while if the RptM button is on, pressing the PMod button will play the wav file repeatedly.

Please note that the wav files used for modulator or carrier sources must have a 16 bit, monophonic, 11.025 Khz format. If the wav files do not have this format they will not be loaded! If you have a file that you want to use that does not have this format, you can convert it to the required format with one of the many conversion programs that are available (such as CoolEdit, SoundForge,...).

One benefit of using wav files as carrier or modulator signal sources over using external inputs is that the wav files are 16 bit signals, while the external inputs are only digitized to 8 bits. Thus higher fidelity and lower noise results can be obtained by using the wav files than with external inputs.

NOTE: The LCar and LMod functions are not available in the demo version!

Voiced/Unvoiced Detection

When the   V/UV [image]    button is pressed the vocoder runs a voiced/unvoiced detection process.

This process determines whether the modulator signal is a voiced sound (such as a vowel, - e.g. "ee" "aah" "ooh", etc.) or an unvoiced sound (such as a plosive or consonant or sibilant, - e.g. "t" "k" "ss", etc.). When an unvoiced sound is detected by this process, the carrier signal (whatever its source) is replaced by a white noise signal. The reason for using this process is that most carrier signals (such as the internally generated pulse signals) do not have the broad spectral content that is found in unvoiced sounds and hence can not accurately imitate such sounds.

Frequency Modulation

The frequency of the internally generated pulse and chorus signals is modulated via a low frequency square wave when the   Yodel [image]   button is pressed on. The frequency of this modulation is set by the RATE slider. This results in a kind of a "yodeling" effect, although it is nowhere near as good as the yodel effect heard in Kraftwerk's "Autobahn". Interesting effects can be obtained when this is used in conjunction with the Sample/Hold mode (obtained by pressing the S/H button).

Pitch Tracking

The internally generated pulse and chorus carrier waveforms result in sounds that are very "robotic". Part of the reason for this is that the frequency of these waveforms is constant.

A more natural speech sound can be obtained if the frequency of the carrier waveforms could be made to track the pitch of the modulator speech signal. Obtaining accurate pitch tracking is a non-trivial process, however, and good low noise algorithms require a lot of computing power. The Cylonix vocoder uses a very simple process which doesn't track the modulator pitch very well, but

provides a fairly low noise tracking and an interesting sound.

Pressing the   Track [image]   button on enables this tracking process.

The pitch tracker works best with slowly changing speech. Don't talk quickly! The tracker seems to sound best when a complex carrier is used (such as the chorus signals) and with a positive spectral shift of two or three places.


Filter Bandwidth

The nature of the sound produced by the channel vocoder is in large part determined by the filters used in the analysis and synthesis channels. In the Cylonix vocoder, three different sets of filters can be used. These are all 8th order Butterworth digital filters, but have different bandwidths.

Pressing the    Nrrw [image]   button causes a narrow band version of the analysis and synthesis filters to be used. These filters have half the bandwidth of the usual filters (i.e. they are 1/6th of an octave wide instead of 1/3rd of an octave wide). This produces a somewhat hollow  and reverberant sound, due to the increased ripple in the time-domain impulse resonse of the filter.

Pressing the    Wide [image]   button causes a wide band version of the analysis and synthesis filters to be used. These filters have twice the bandwidth of the usual filters (i.e. they are 2/3rds of an octave wide instead of 1/3rd of an octave wide). This produces a somewhat less distinct and muffled sound than wid\th the normal filter set. Pressing the Comb button, when the wide filters are selected will set the level of every other synthesis channel to zero, resulting in what is effectively a 9 channel vocoder.

Pressing the    Norm [image]   button causes the normal bandwidth version of the analysis and synthesis filters to be used. These filters have a bandwidth of the 1/3rd of an octave.

The filters are all implemented as 8th order (48 dB/octave cutoff) Butterworth digital bandpass filters having a selectable bandwidth of either 1/6, 1/3 or 2/3 octave. The centre frequencies, (rounded to the nearest Hertz), of the filters are as follows:

108, 137, 172, 217, 273, 344, 434, 547, 689, 868, 1093, 1378, 1736, 2187, 2756, 3472, 4375, 5512

Vocoder afficionados will notice that, unlike most hardware vocoders, the lowest and highest frequency filters are bandpass filters rather than lowpass or highpass. On the low end this is because of the fact that the Creative Labs Soundblaster cards have a low frequency rolloff of around 50Hz, so that there wouldn't be any significant difference between using a lowpass or a bandpass filter. On the high end, the antia-aliasing filtering done by the sound card for a sampling rate of 11,025Khz (which is the rate used in the Cylonix program) enforces a high frequency cutoff of 5,512Khz, So, using a highpass filter would provide no significant difference to the sound than using a bandpass filter.


Channel Level Controls

The output level of each of the synthesizer section filters is modulated by the control signals generated by the analyzer section. This modulation, of course, changes over time as the modulation signal changes. The Cylonix vocoder, however, provides an additional control over the output level of the synthesizer section filters. This can be used to to static shaping of the output spectrum, for example to enhance or suppress a particular frequency.

Each of the vocoder channels has an associated level slider which can be used to control the level of a channel independantly of the other channels.

There are four buttons which set the channel level sliders into often used configurations.

These are:

Rand    Zero    Full    Comb

The Rand button randomizes the settings of the level sliders. This is useful for experimenting and fooling around, and when you haven't got a clue of what you are doing.

The Zero button sets all channel levels to zero. This is useful when you just want a few of the channels to be heard. You just hit the Zero button and then manually set those few channels to the desired level.

The Full button sets all channels to their full level. This is useful in resetting the vocoder to its normal operational mode.

The Comb button zeroes the level on every other channel. This provides a narrow band effect similar to that obtained from some inexpensive hardware vocoders that are on the market (and which shall remain nameless!).

NOTE: In the unregistered version of the program, moving the channel level sliders with the mouse has no effect on the channel levels. Use of the channel level preset buttons will change the levels, however.


Gain Control

The GAIN slider controls the overall output level of the vocoder. This should be set to as high a level as possible without causing distortion. Some of the spectrum modification modes, such as spectrum inversion, tend to cause distortion and the GAIN slider should be lowered in these cases.

Also, some microphones have much lower levels than others, and require a higher gain setting. Make sure to adjust the levels using the sound card mixer program before adjusting the vocoder GAIN setting!


Mix Control

The MIX slider determines the proportion of modulator signal that will be mixed in with the vocoder output signal. Setting its level to the maximum will bypass the vocoder entirely, and output just the modulator signal.

Note that one can also bypass the vocoder, but this time output just the carrier signal by use of the EQ

mode.


Sibilance Control

The action of the SIBIL slider is similar to the action of the MIX slider, but differs in that only a part of the frequency spectrum of the modulator is passed through. The portion that is mixed in with the output is obtained by high-pass filtering the modulator signal, with a cutoff frequency equal to that of the highest frequency analysis filter.

The purpose of the sibilance effect is to emphasize the unvoiced (i.e. "s" sounds and consonant sounds) components of speech. Most carrier signals do not have the broadband high frequency components neccessary to adequately represent unvoiced speech. Passing through some of the high frequency components from the modulation signal to the vocoder output partially makes up for this lack, and generally produces a more intelligible vocoder output.


Channel Pan Controls

The synthesizer section output is a stereophonic combination of the 18 synthesis filter outputs.

Each of these outputs can be independently panned between the left and right output channels, using the Channel Pan sliders.

There are four buttons which set the channel pan sliders into often used configurations.

These are:

Mono    Sprd   Split     Rand

Pressing the Mono button sets all of the pan sliders to the middle of their range, resulting in a purely monophonic sound.

Pressing the Sprd button sets the even number channel pan sliders to the right and the odd number channel pan sliders to the left. This results in a very wide and open spatial sound.

The Split button sets the pan sliders of the lower 9 channels to the right and the upper 9 channels to the left. This provides a different sort of spatial sound than the Sprd button setting.

The Rand button randomizes the settings of the pan sliders. This is useful for experimenting and fooling around, and when you haven't got a clue of what you are doing.

NOTE: In the unregistered version of the program, moving the pan sliders with the mouse has no effect on the pan positions. Use of the pan preset buttons will change the pan positions, however.


Gain Control

The GAIN slider controls the overall output level of the vocoder. This should be set to as high a level as possible without causing distortion. Some of the spectrum modification modes, such as spectrum inversion, tend to cause distortion and the GAIN slider should be lowered in these cases.

Also, some microphones have much lower levels than others, and require a higher gain setting. Make sure to adjust the levels using the sound card mixer program before adjusting the vocoder GAIN setting!


Introduction

This program implements a filter bank channel vocoder with 18 channels. The program was designed for use with a full duplex Creative Labs SoundBlaster card (e.g. the SB32 or SB64) and a Pentium computer running Windows95. The program should function, however, with any sound card that can operate in full duplex mode and has a Windows multimedia driver. The program runs fine on a 120MHz Pentium but may produce choppy sound with slower computers.

What is a "Channel Vocoder", you ask?  A channel vocoder is a device for compressing, or encoding, the data needed to represent a speech waveform, while still retaining the intelligibilty of the original waveform. The first channel vocoder was developed by Homer Dudley in 1936. It passed the speech signal through a bank of band-pass filters. These filters each covered a portion of the audio spectrum. The energy of each filter's output was then measured, or sampled, at regular time intervals and stored. This collection of filter energy samples then comprised the "coding" of the speech signal. This code could then be transmitted over a communication channel of lower bandwidth than would be neccessary for the raw speech signal. At the receiving end, the speech signal is reconstructed from this code by using the time sequence of filter energy samples to modulate the amplitude of a pulse signal being fed into a bank of filters similar to the ones used for the encoding. The result, while clearly not the original speech signal, is nonetheless intelligible, and one can, in most cases, understand what is being said.

A block diagram of the overall process is shown in the figure below.

The idea for the channel vocoder technique arises from the manner in which speech is generated in the human vocal tract. Simply put, the vocal chords produce a periodic, pulse-like, stream of air, which is then acoustically filtered by the elements of the vocal tract: the esophagus, tongue, lips, teeth, and the oral and nasal cavities. As one speaks different sounds, the shape and elastic properties of these elements are being constantly changed in response to neural signals arising from speech centres in the brain. This causes a time-varying filtering, or spectral variation, of the excitation arising from the vocal chords.

The channel vocoder, then, first analyzes the speech signal to estimate this time-varying spectral variation. To do this it uses the filters in the filter banks to determine how a particular frequency component of the speech signal is changing with time. On the output end, this analysis of the spectral variations are used to synthesize the speech signal by using another filter bank to apply these same spectral variations to an artificial periodic pulse like signal. The output filter bank acts as an artificial vocal track and the pulse signal acts as a set of artificial vocal chords.

Some sounds produced during speech do not arise from the vocal chords, but are produced by turbulent air flow near constrictions in the vocal tract such as may occur between the tongue and the teeth. For example, such sounds as "SSS", "K", "SSHH", "P", and so forth arise in this manner. These sounds would be poorly reconstructed using a pulse excitation source, and so most channel vocoders also have a noise signal that can be used as an excitation source as well. A "Voiced/Unvoiced" detector circuit is used to detect whether the speech signal is arising from vocal chord excitation (Voiced speech) or is arising from noise excitation (Unvoiced speech), and the appropriate excitation source is then selected at the output end.

Channel vocoders were originally developed for signal coding purposes, with an eye (ear?) towards reducing the amount of data that would be needed to be transmitted over communication channels.

In fact, speech coding system development continues to this day to be a vigorous area of research and development. These systems have far outstripped the basic channel vocoder idea in complexity, coding efficiency, and intelligibilty, however. So why have we produced this program? The reason is that channel vocoders (and the functionally equivalent, but computationally quite different, phase vocoder) have found application to music production. In the 1960's Siemens in Germany produced a vocoder which was used in some recordings. The BBC Radiophonic Workshop in England likewise pioneered the use of vocoders in recording and in radio and television. The vocoders used in these early musical efforts were very large and unsuited to general use. In the mid-70's a breakthrough of sorts came about when a number of companies, notably EMS (Electronic Music Studios) in England, produced relatively small and easy to use vocoders designed for use in musical applications. After that, the vocoder sound became a staple of the music and entertainment industry. Many extremely popular records (Kraftwerk!), TV shows (the Cylons of Battlestar-Galactica), and movies (Darth Vader in Star Wars) are identfied with vocoders.

Although the introduction of these relatively small vocoding systems made it possible for the wide application of vocoders to music and film, they were still quite expensive for your average musician in the street. The EMS vocoder cost upwards of 6500 UK pounds! There are now less expensive  vocoders on the market now, but these attain their low price at the expense of limited functionality. This is where the Cylonix vocoder comes in. For a price of 1/200 that of the EMS vocoders you can get a similar level of functionality! The Cylonix vocoder has the following sets of features, some of which are to be found only on the most expensive of the hardware vocoders.

FEATURES OF THE CYLONIX VOCODER

Number of Channels: 18

Channel Filter Cutoff Rate: 48 dB/octave

Choice of 3 different filter bandwidths

Sibilance Feedthrough

Simple Pitch Tracking

Spectrum Shifting

Spectrum Sampling and Hold

Adjustable Analyzer/Synthesizer Spectrum Mapping Matrix

Graphical Spectrum Energy Display

Stereo Output with Pan and Level Control of all 18 Synthesizer Channels

Voice/Unvoiced Detector

Internal Adjustable Frequency Pulse Oscillator and Noise Generator

Recording of Vocoder Output

Loading of WAV Files for use as Carrier and Modulator Sources

Randomization of Spectrum Mapping

Some Other Commercially Available Vocoders

Here are specifications of some commercially available hardware vocoders. Compare the capabilities of these vocoders to those of the Cylonix vocoder. You will get a feeling for the power of the Cylonix program. Please keep in mind that the great majority of these commmercial machines cost hundreds or even thousands of dollars! Compare this to the low price of the Cylonix vocoder.

EMS 5000:

Analog

Price:  around 6500 UK pounds

Number of Channels: 22

Filter Order: 8th order

Channel levels can be adjusted with external Control Voltage (CV) inputs

Pitch extractor

2 built in oscillators (VCOs) with square wave and ramp outputs

One noise source

Voiced/unvoiced detector

Slew/Freeze control can be manually operated with a variable control or

freeze switch.

Frequency shifter stage with a range of .05Hz to 1 kHz

Patching of analyzer and synthesizer channels with a matrix of 22 x 22 patchpoints.

EMS-2000

Analog

Price: 1000 UK pounds

Number of channels: 16

Filter Order: 6th order

Internal pulse oscillator and white noise source

Voiced/Unvoiced detector

Spectrum Slew/Freeze (Hold)

SYNTON 221

Analog

Price: around $7500 US

Number of channels: 20

Filter cutoff: 54 db/octave

Channel patching Matrix-panel

Internal VCO

noise generator

Voiced/Unvoiced detection

LEDs for spectrum monitoring

External control inputs/outputs for each channel

SYNTON 222

Analog

Price: $625 US

Number of channels: 12.

SYNTON 202

Analog

Price: $500 US

Number of channels: 10

No noise generator.

SYNTON SPX-216

Analog

Price: $1000 US

Number of channels: 14

VCO and noise generator

Carrier compression & distortion

Rear-connector for CV in/out.

ELECTRO-HARMONIX VOCODER

Analog

Price 400 UK pounds

14 channels

ROLAND SE70

10 and 21channels in the same unit

Digital Effects box

ROLAND SVC-350

Analog

11 channels

Compressor on Mic input

Spectrum Hold

24db/octave filter cutoff

KORG VC-10

Analog

comes with keyboard

Compressor on mic input

1 master oscillator and 1 oscillator per key

 3 low frequency oscillators (LFO's) for vibrato

20 channels

24 dB/octave filter cutoff

BODE 7702

Analog

16 channels

Analyzer-Synthesize channel patching

Pulse (buzz) and Noise (hiss) generators

Spectrum Sample and Hold

SENNHEISER VSM201

Analog

Price: 10,000 UK pounds

20 channels

36 dB/octave filter cutoff

Fixed 150Hz pulse generator

Noise source

Voiced/Unvoiced detector with filter

Döpfer A-129

Analog

Price: about $400 US for basic module

Made in conjunction with Kraftwerk.

15 channels

24 dB/decade filter cutoff

Modular, allowing complex processing by adding other Döpfer mdoules

ELECTOR

Analog kit

10 channels

24 db/decade filter cutof

Noise generatorf

Voiced/Unvoiced detector

Sibilance

Engineered in conjunction with Synton.

PAIA

Analog kit

Price: $100 US

8 channels

12 dB/decade filter cutoff

Sibilance

Carrier distortion


Registration

This program is shareware and, as such, regular users of this program are expected to register it.

The Cylonix 18 channel vocoder program is Copyright James J. Clark, 1997

Load and Save operations do not function in the unregistered (demo) version of the program. In addition the settings of the channel level and pan position sliders are not updated when the associated slider controls are moved with the mouse in the demo version. Adjustment of the analyzer-synthesizer channel mapping with the mouse is likewise not supported in the demo version.

Free use (and distribution) of the unregistered version of the Cylonix 18 Channel Vocoder program is granted under the conditions that the output of the program, whether subsequently modified or not, can not be used for any commercial purpose. There is no such restriction on registered versions of the program.

Registration of the program requires obtaining a license code from Cylonix. This number is then stored in a file located in the same directory as the vocoder executable. To obtain the license code for your program, press the "r" button on the keyboard while running the vocoder program. A dialog box will appear displaying a serial number. Send a message listing this serial number by email to cylonix@videotron.ca. You will be sent a return message giving instructions on how to send payment for the license.

The current licensing fee for the program is $40 in Canadian funds or $30 in US funds. Please contact cylonix@videotron.ca to obtain the most current licensing fees.

The licensing fee can be remitted either in the form of a check drawn on a US or Canadian bank or a money order. We will then return to you by email and/or post a copy of the license code for your program.

Please make sure that the demo program runs satisfactorily on your system before ordering the license!


Saving/Loading Your Settings

In the course of playing around with the vocoder controls you may happen across a configuration that you particularly like. This configuration can be saved for future recall by pressing the  SSet

button. Pressing this button will produce a dialog box prompting you for the name of a file in which to store the current control settings. Also stored is the spectrum mapping if the Rand button is on.

These settings can then be restored at a future time by pressing the   LSet [image]   button. Pressing this button will produce a dialog box prompting you for the name of a settings file.

When you exit the vocoder program, the control settings at the time of exit are stored in a file named "session.set" in the vocoder executable directory. When the vocoder program is started up again, this file will be read in and the vocoder controls set to the state that they had when the program stopped previously.

NOTE: The settings saving and loading functions are not available in the demo version!


Spectrum Display

The Cylonix vocoder includes a graphic display of the modulator signal energy in each of the 18 channels. This display is similar to spectrum analyzers found in many home stereos.

The display is updated approximately 11 times a second. It includes a fast responding display (the yellow bars) and a time-averaged display (the red lines). The vertical scale of the display is a compressed, approximately logarithmic, function of the channel energy. The display can therefore display a wide range of modulator signal energies.