ben m
Joined: 15 Sep 2002
Posts: 337
Location: UK |
| Week 5 - Synthesis 2 |
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More synthesis questions here for you - everybody needs to catch up on synthesis 1 first however.
It's not a good idea to fall behind this early in as it will make it harder to catch up in subsequent weeks!
 a) Which method of additive synthesis had widespread commercial success in the 1980s?
b) Describe the basic principles of this method of synthesis.
c) How this was implemented in the synthesisers that were commercially available.
What are the ADSR characteristics of the following instruments;
Piano
Guitar
Snare Drum
Violin
Describe the effect of the following modulations:
a) A VCO is going into a VCF and to a VCA. The VCO is being modulated by another VCO producing a square wave with a frequency of 15 Hz.
b) A VCO is going into a VCF and to a VCA. The VCF is being modulated by an ADSR.
c) A VCO is going into a VCF and to a VCA. The VCA is being modulated by another VCO producing a sine wave with a frequency of 10 Hz.
In early analogue subtractive synthesis, describe the difference between a voltage controlled oscillator and a conventional oscillator.
In subtractive synthesis, describe the function of the resonance control in a low-pass filter.
Describe three common ways an LFO might be used in analogue synthesis. Include references to other components of analogue synthesisers. Do not use abbreviations in your answer.
Give four terms used in FM (Frequency Modulation) synthesis and not in analogue synthesis.
Describe the waveform source in a wavetable synthesiser.
What technical problem would you expect to encounter when using an old analogue synthesizer for a lengthy live performance, even if the synthesizer is working to its original specifications?
What would be the effect of modulating the VCF of an analogue synthesizer with the LFO?
On the ADSR of an analogue synthesizer, how would you make a note decay to complete silence, no matter how long the key is pressed?
In an FM synthesizer, how would you quickly make a major (but probably random) change in the sound produced?
In an FM synthesizer, what would you adjust to change the high frequency content of a sound?
Which would you expect to sound best on an FM synthesizer: a tinkly electric piano sound or an imitation of string instruments?
Describe how frequency modulation can be achieved with a traditional analogue synthesizer, or modern equivalent. How will the end result differ compared to an FM synthesizer? |
Mon Apr 05, 2004 11:24 pm |
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hoggs33
Joined: 09 Feb 2004
Posts: 55
Location: Nottingham, England |
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Which method of additive synthesis had widespread commercial success in the 1980s?
FM synthesis - a good example is the DX7 synth.
Describe the basic principles of this method of synthesis.
This type of synthesis produces waveforms by adding together sine waves. This is based on the Fourier Theory – Jean Baptiste Fourier proved that any periodic waveform can be expressed as a sum of one or more sine waves. This meant that in theory, it was possible to build any sound imaginable from simple sine waves. As a result of this additive synthesis is a hugely versatile technique.
How this was implemented in the synthesisers that were commercially available.
As referred to above the DX7 is the best example of a commercially available additive synth during the 80’s. It was a 16 voice polyphonic synth with 32 internal memories plus a ROM/RAM cartridge. The synthesis was implemented as a series of ‘operators’ that the instrument offered to the user in a number of different configurations or ‘algorithms’. The operators were all sine waves, and each could be either a carrier wave or a modulator wave, depending on its position or relationship with another wave in a particular algorithm. The DX7 used six operators per voice.
What are the ADSR characteristics of the following instruments
;
I had some nice graphical illustration to show these saved as Gif files but they wouldn't upload 
Piano – Quick attack, followed by a slow decay and release with a long sustain – se diagram below
Guitar – Quick attack similar to a piano, but shorter delay, release and sustain.
Snare Drum - A drum beat has a percussive envelope and, like a plucked string, it will have an almost instant decay. The sound is not sustained or released.
Violin – A slow attack followed by a long sustain, and then a slightly faster release. There is no decay between the attack and the sustain stages.
Describe the effect of the following modulations:
A VCO is going into a VCF and to a VCA. The VCO is being modulated by another VCO producing a square wave with a frequency of 15 Hz. –
The second VCO makes the first VCO rapidly switch between two frequencies, 15 complete up/down cycles a second.
A VCO is going into a VCF and to a VCA. The VCF is being modulated by an ADSR.
The VCF makes the filter cut-off frequency change according to the ADSR settings/envelope result in timbre changes.
A VCO is going into a VCF and to a VCA. The VCA is being modulated by another VCO producing a sine wave with a frequency of 10 Hz.
This will produce a tremolo effect as the output level will fluctuate.
In early analogue subtractive synthesis, describe the difference between a voltage controlled oscillator and a conventional oscillator.
A voltage controlled oscillator is an analogue circuit that generates an electrical wave, such as Sine, Sawtooth or Square – these were the raw sound tone generators on early analogue synths. A conventional oscillator is an electrical circuit which produces simple electric waves, at given frequencies.
In subtractive synthesis, describe the function of the resonance control in a low-pass filter.
A low pass filet is a filter whose frequency response remains flat up to a certain frequency, then rolls off above those point. Each filter also has a resonance control. Filters do not just attenuate the frequencies defined by the cut off control – they also boost certain frequencies around the Cut Off point, and this is referred to as resonance. The resonance control alters the amount of attenuation that is given to the signal around the cut off point.
Describe three common ways an LFO might be used in analogue synthesis. Include references to other components of analogue synthesisers. Do not use abbreviations in your answer.
1- To modulate the frequency of a voltage controlled oscillator
2- To modulate the level of the signal via the voltage control amplifier
3- To modulate the frequency content of the signal via the voltage controlled filter.
Give four terms used in FM (Frequency Modulation) synthesis and not in analogue synthesis.
Algorithm
Operator
Carrier
Modulator
Describe the waveform source in a wavetable synthesiser.
A wavetable synthesizer has a ROM containing data describing waveforms. These waveforms may be digitally encoded versions of the basic sound sources of analogue synthesis, or they may be completely new types of waveforms or even samples.
What technical problem would you expect to encounter when using an old analogue synthesizer for a lengthy live performance, even if the synthesizer is working to its original specifications?
The tuning of the VCO will drift.
What would be the effect of modulating the VCF of an analogue synthesizer with the LFO?
The high frequency content of the signal will increase and decrease repeatedly. It would create a wah-wah effect.
On the ADSR of an analogue synthesizer, how would you make a note decay to complete silence, no matter how long the key is pressed?
Set the sustain level to zero
In an FM synthesizer, how would you quickly make a major (but probably random) change in the sound produced?
Change the algorithm
In an FM synthesizer, what would you adjust to change the high frequency content of a sound?
Adjust the parameters of one of the operators
Which would you expect to sound best on an FM synthesizer: a tinkly electric piano sound or an imitation of string instruments?
Tinkly electric piano
Describe how frequency modulation can be achieved with a traditional analogue synthesizer, or modern equivalent. How will the end result differ compared to an FM synthesizer?
The low frequency oscillator is assigned to modulate the pitch of one of the voltage controlled oscillators. At low frequencies of the LFO, this will create vibrato but at frequencies higher than around 20Hz the note will change in character according to the ratio of the frequencies between the VCO and LFO. Unless the frequency of the LFO can track the keyboard, the character of the sound will change for each note because the ratios of the two frequencies will change. |
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Thu Apr 08, 2004 7:05 pm |
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iNSTiNCT2765
Joined: 05 Nov 2003
Posts: 60
Location: Denmark |
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Week 5 – Synthesizers 2
a) Which method of additive synthesis had widespread commercial success in the 1980s?
Additive synthesis is a type of synthesis and I couldn’t find any subtypes of it. A synth that uses the technology is the Kawai K5 (1987).
b) Describe the basic principles of this method of synthesis.
Additive synthesis emulates the way sound is created naturally with multiple harmonics. To do this, it employs multiple oscillators, each creating a simple sine wave. The frequency and amplitude for each can then be set individually. Combining these waves together creates one complex waveform.
c) How this was implemented in the synthesisers that were commercially available.
Commercially available synthesizers like the Kawai K5 use digital harmonic generators (DHG) as oscillators, a digital dynamic filter (DDF) as a filter and a digital dynamic amplifier (DDA) as the amplifier.
What are the ADSR characteristics of the following instruments?
Piano – fast attack/ slow decay/ no sustain/ medium release
Guitar – fast attack/ slow decay/ no sustain/ medium to long release
Snare Drum – fast attack/ medium decay/ no or fast sustain/ medium release
Violin – slow attack/ long decay/ long sustain/ fast to medium release
Describe the effect of the following modulations:
a) A VCO is going into a VCF and to a VCA. The VCO is being modulated by another VCO producing a square wave with a frequency of 15 Hz.
This makes the VCO move rapidly up and down 15 times a second.
b) A VCO is going into a VCF and to a VCA. The VCF is being modulated by an ADSR.
This results in a filter sweep that follows the characteristics of the ADSR.
c) A VCO is going into a VCF and to a VCA. The VCA is being modulated by another VCO producing a sine wave with a frequency of 10 Hz.
The amplifier is fluctuating at a speed of 10 times a second resulting in a tremolo effect.
In early analogue subtractive synthesis, describe the difference between a voltage controlled oscillator and a conventional oscillator.
The output frequency of the VCO is dependant on the voltage applied to the VCO while conventional oscillators use a fixed frequency that can be changed but is not dependant on the voltage applied.
In subtractive synthesis, describe the function of the resonance control in a low-pass filter.
The low-pass filter determines the frequency above which harmonics are removed and below which pass unaffected. This point is called the Filter Cut-off Point. The resonance control boosts the harmonics around the Filter Cut-off Point. Working the resonance control slider/fader in real-time can produce nice sweeping effects.
Describe three common ways an LFO might be used in analogue synthesis. Include references to other components of analogue synthesisers. Do not use abbreviations in your answer.
The low frequency oscillator works at a slow set rate varying from approximately 0.1Hz to 10Hz. Its parameters can include:
1) Waveform selection – choice between sine, triangle, square and saw waves.
2) Rate – the speed of the oscillation
3) Delay – the time before it starts
The triangle and sine waves have regular rise and falls while the square and saw waves have sharp jumps. Three ways the low frequency oscillator can be used in analogue synthesis is to produce the following effects:
1) Vibrato: using the low frequency oscillator to modulate the voltage controlled oscillator carrying a sine or triangle wave causes the pitch to vary smoothly up and down or in other terms, wobble, producing a vibrato effect. Using the same procedure with a saw waveform will produce a siren and using it with a square wave will produce a ‘thrill’ or sudden varying of the pitch.
2) Wah-Wah: modulating the cut-off of the voltage controlled filter using the low frequency oscillator can produce a wah-wah sound.
3) Tremolo: if you modulate the voltage controlled amplifier using the low frequency oscillator, the loudness of the output varies. If the input is a sine or triangle waveform, a tremolo effect is produced since the volume is varying smoothly.
Give four terms used in FM (Frequency Modulation) synthesis and not in analogue synthesis.
Operator, Carrier, Algorithm, Modulator.
Describe the waveform source in a wavetable synthesiser.
The waveform source in a wavetable synth is a ROM chip that has pre-recorded samples digitally stored on it. Due to the expense of ROM chips, to fit many sounds on one chip, only a small portion of the sustain of the sample is recorded, which is then looped. It is also processed using amps and filters to give a natural decay
What technical problem would you expect to encounter when using an old analogue synthesizer for a lengthy live performance, even if the synthesizer is working to its original specifications?
I couldn’t find anything on this!!!
What would be the effect of modulating the VCF of an analogue synthesizer with the LFO?
The effect would be a wah-wah effect.
On the ADSR of an analogue synthesizer, how would you make a note decay to complete silence, no matter how long the key is pressed?
This can be achieved by eliminating the sustain.
In an FM synthesizer, how would you quickly make a major (but probably random) change in the sound produced?
Could this be done by muting one of the oscillators?!?
In an FM synthesizer, what would you adjust to change the high frequency content of a sound?
By decreasing the pitch of the modulator?!?
Which would you expect to sound best on an FM synthesizer: a tinkly electric piano sound or an imitation of string instruments?
A tinkly electric piano sound.
Describe how frequency modulation can be achieved with a traditional analogue synthesizer, or modern equivalent. How will the end result differ compared to an FM synthesizer?
All I can get here is that you can use the LFO to modulate the frequency of the VCO in an analogue synth. I couldn’t find anything on this. |
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Fri Apr 09, 2004 11:14 pm |
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griff505
Joined: 23 Feb 2004
Posts: 68
Location: Bristol |
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a) Which method of additive synthesis had widespread commercial success in the 1980s?
FM Synthesis, e.g. Yamaha DX7 – Brian Eno, Level 42, Daryl Hall.
b) Describe the basic principles of this method of synthesis.
Frequency Modulation Synthesis is where the output of one oscillator (the Modulator) is used to modulate the pitch of another (the Carrier). The pitch of the Carrier is being changed (modulated) in tandem (in sync/ going up and down at the same time) by the Modulator.
The carrier frequency (C) and the modulator frequency (M) will together determine which harmonics will exist, or have the possibility to exist in the harmonic spectrum. The harmonic spectrum is a graphic representation of frequencies where "1" is the fundamental frequency and the other harmonics are just multiples of the fundamental. From this any sound can be formed from sine waves.
c) How this was implemented in the synthesisers that were commercially available.
In the Yamaha DX7 the hardware comprises a number of Operators, tone generators in much the same way as the oscillators in an analogue synth, complete with a voltage controlled output amplifier tacked on the end to modify the amplitude against time of the oscillator's output. Yamaha designed the system so that the Operators can be configured into any one of 32 different interconnection patterns, some in parallel with each other, some with their output feeding the input of the next Operator. These interconnections are referred to as Algorithms. Whenever the output of one Operator modulates the input of the next a shift in output frequency of the modulated Operator occurs in direct proportion to the amplitude of the modulating source. Careful tweaking of levels and associated time parameters results in sounds of a most complicated nature, including very close approximations to real instruments.
What are the ADSR characteristics of the following instruments;
Piano - fast attack, short decay, very short sustain, and long release.
Guitar – fast attack, short decay, very short sustain, long release.
Snare Drum – fast attack, instant decay, no sustain, no release.
Violin – slow attack, no, decay, long sustain, fast release.
Describe the effect of the following modulations:
a) A VCO is going into a VCF and to a VCA. The VCO is being modulated by another VCO producing a square wave with a frequency of 15 Hz.
The second VCO modulates the first between two frequencies (because it is a square wave) at a rate of 15 times per second (15 Hz).
b) A VCO is going into a VCF and to a VCA. The VCF is being modulated by an ADSR.
The VCO will be affected by the cut-off frequency of the filter according to the ADSR characteristics.
c) A VCO is going into a VCF and to a VCA. The VCA is being modulated by another VCO producing a sine wave with a frequency of 10 Hz.
This will result in an LFO or tremolo effect as the sine wave modulates the amplifier at a rate of 10 times per second.
In early analogue subtractive synthesis, describe the difference between a voltage controlled oscillator and a conventional oscillator.
Subtractive Synthesis - The technique of arriving at a desired tone colour by filtering waveforms rich in harmonics. Subtractive synthesis is the type generally used on analog synthesizers.
VCO - An oscillator whose clock frequency is determined by the magnitude of the voltage presented at its input. The frequency changes when the voltage changes. The most common form of tone (pitch) source, which usually provides simple repetitive waveforms rich in harmonics. The Control Voltage is usually supplied by a keyboard with a resistor chain or an external input.
Conventional Oscillator – These use a fixed frequency which an be changed, but are not controlled by voltage.
In subtractive synthesis, describe the function of the resonance control in a low-pass filter.
Resonance is the amount of the output from the filter that is fed back into the input. Its effect is to emphasise the frequencies around the cut off frequency. Increasing the resonance makes the filter effect more dramatic, particularly with filter sweeps. On many synths, if the resonance is turned right up it feeds back on itself and turns into another oscillator.
(Cut off frequency determines the frequency at which the filter starts to take effect. Below this frequency (in the case of a low pass filter) the signal will not be affected. Above it, the signal will be filtered. The lower the frequency, therefore, the more of the total signal will be removed (if you set the filter cut off frequency below the actual fundamental frequency of the note you are playing, the signal will be almost entirely removed.) There is normally a knob on an analogue synthesizer to set the base cut off frequency for the filter. This base frequency can then be changed (i.e. modulated) by various control voltages (envelope generator, LFO, etc) to give filter sweep effects. Sweeping the filter cut off frequency can give very dramatic effects (e.g. the constantly changing sound of an acid bass line, with the filter being slowly swept slowly up & down by an LFO)).
Describe three common ways an LFO might be used in analogue synthesis. Include references to other components of analogue synthesisers. Do not use abbreviations in your answer.
The Low Frequency Oscillator produces a signal with a relatively low frequency, ranging from 1 cycle a minute up to maybe 10 times a second (10 Hertz). The LFO is not used to generate a signal that you can hear, but is used to modulate the other parts of the synth to generate effects.
Three common ways an LFO may be used include the modulation of:
- Oscillator Frequency - A fairly fast (say 5Hz) sine wave voltage from the Low Frequency Oscillator can be applied to the main oscillator to produce a vibrato effect. The output of the Low Frequency Oscillator is usually fed to a Modulation Wheel before going to the oscillator which allows the vibrato level to be controlled in real time.
- Filter Cutoff - A fairly fast Low Frequency Oscillator can be used to give a sort of bubbling effect when applied to the filter. A very slow (0.1 Hz) Low Frequency Oscillator sweep can be used (particularly with a lot of resonance on the filter) to give a constant swooshing up/down.
- VCA - Modulating the Voltage Controlled Amplifier a little with a fairly fast Low Frequency Oscillator gives a tremolo effect such as that found on electric pianos.
Give four terms used in FM (Frequency Modulation) synthesis and not in analogue synthesis.
- Operators
- Algorithms
- Carrier
- Modulator
Describe the waveform source in a Wavetable synthesiser.
Wavetable synthesis uses digital tables of sounds, frequently sampled, to provide the initial source, usually for subtractive synthesis. Segments of digital audio are played to produce a realistic instrument or synthetic sound. The digital audio segments are stored as a table of waveforms in memory and played back at different speeds to produce output of a different pitch for each musical note. Each instrument waveform contains a loop region which starts after the attack segment of the digital audio has played and repeats while the instrument's note is sustained (i.e. while a note is held). Then the release segment of digital audio finishes off the note. Wavetable synthesis in the form of envelopes and modulators are often combined with AM synthesis to add some variation to otherwise repetitive sounding output.
What technical problem would you expect to encounter when using an old analogue synthesizer for a lengthy live performance, even if the synthesizer is working to its original specifications?
Analogue VCO’s are liable to drift out of tune, requiring periodic retuning by an engineer; temporary tuning drift is caused by temperature fluctuations - synthesisers with VCO’s must be switched on well before a gig in order for them to be in tune by the time it starts.
What would be the effect of modulating the VCF of an analogue synthesizer with the LFO?
A fairly fast Low Frequency Oscillator can be used to give a sort of bubbling / wah-wah effect when applied to the filter. A very slow (0.1 Hz) Low Frequency Oscillator sweep can be used (particularly with a lot of resonance on the filter) to give a constant swooshing up/down.
On the ADSR of an analogue synthesizer, how would you make a note decay to complete silence, no matter how long the key is pressed?
Set the sustain level to zero.
In an FM synthesizer, how would you quickly make a major (but probably random) change in the sound produced?
Change the modulation amount – this will affect the loudness and amplitude of the Carrier and each order of Sidebands.
In an FM synthesizer, what would you adjust to change the high frequency content of a sound?
The Carrier frequency
Which would you expect to sound best on an FM synthesizer: a tinkly electric piano sound or an imitation of string instruments?
Tinkly piano sound.
Describe how frequency modulation can be achieved with a traditional analogue synthesizer, or modern equivalent. How will the end result differ compared to an FM synthesizer?
A fairly fast (5Hz) sine wave voltage from the LFO can be applied to the main oscillator, to produce a vibrato effect. This only changes the volume of the sound produced by the oscillator as opposed to the changing of the whole character of the sound as in FM synthesis. |
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Sun Apr 11, 2004 2:24 am |
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ben m
Joined: 15 Sep 2002
Posts: 337
Location: UK |
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Good work here.
A few points to pick up on;
Instinct - as you've probably seen from the other answers ,the additive synthesis questions are referring to FM synthesis. Additive synthesis is obviously any form of synthesis whereby the sounds are created primarily by additive methods (i.e. the use of several operators etc) This in the opposite of analogue synthesis which works bu subtracting elements of the sound using filters etc.
Also, the ADSR questions. Think carefully about this, specifically the piano and to a lesser degree the guitar.
What does a sustain pedal on a piano do?
Think of how ADSR characteristics are used to create sounds to be played from a MIDI keyboard. The sustain portion of the note is essentially determined by how long you hold the key down for, and the release comes after the key is released unless there is a minimal sustain period.
Could the ADSR envelopes be 'altered' to provide a suitable manner of replicating the original sounds when triggered from a MIDI keyboard?
It would also be in your benefits to look into why analogue synthesisers can lose their tuning when being used on tour, or in different climates. |
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Sun Apr 11, 2004 8:41 pm |
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albertom
Joined: 21 Jan 2004
Posts: 22
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a) Which method of additive synthesis had widespread commercial success in the 1980s?
FM synthesis
b) Describe the basic principles of this method of synthesis.
The system uses digital sine wave operators. One operator is assigned as the carrier which is the output waveform operator and is placed last in the array. The other operators normally act as modulators and shape the sound of the carrier by frequency modulation. Digital algorithms allow the operators to perform according to a pre programmed configuration, a number of factory assigned algorithms are included within the parameters of the instrument.
c) How this was implemented in the synthesizers that were commercially available.
Yamaha dominated the FM scene in the 80's with the DX7 and the DX11, a cut down later version. The DX7 offered six on board operator's sixteen-note polyphony (massive for the 80's) as well as a filter and the usual envelope shapers. The DX11 used just four operators, had ADRS dynamic shaping, basic filters and only sported 8-note polyphony despite having multi timbre capability with zoning. The DX7 was the biggest selling all time FM synth, also made famous by heavy use on Steve Winwards "Arc of a Diver" Album.
What are the ADSR characteristics of the following instruments;
Piano
Guitar
Snare Drum
Violin
Piano can display: fast attack, slow decay, no sustain, fast release. (depends on playing and pedal use)
Guitar can display: fast attack, slow decay, no sustain, fast release (if damped)
Snare drum displays fast attack, fast decay, no sustain, no release.
Violin can display: fast attack, no decay, long sustain, and fast release. Depends on how the instrument is bowed.
Describe the effect of the following modulations:
a) A VCO is going into a VCF and to a VCA. The VCO is being modulated by another VCO producing a square wave with a frequency of 15 Hz.
The pitch of the VCO will rise sharply up and down at a rate of 15 times a second. The amount of pitch increase and decrease will depend upon the amount of modulation applied to the VCO control circuit.
b) A VCO is going into a VCF and to a VCA. The VCF is being modulated by an ADSR.
The sound will filter sweep in accordance with the settings of the ADSR. This is how the classic Moog scream is produced.
c) A VCO is going into a VCF and to a VCA. The VCA is being modulated by another VCO producing a sine wave with a frequency of 10 Hz.
This will provide a 10Hz tremolo effect.
In early analogue subtractive synthesis, describe the difference between a voltage controlled oscillator and a conventional oscillator.
A conventional oscillator is fixed frequency set by a preset, although the frequency can be altered by adjusting the preset. A voltage-controlled oscillator is real-time variable across its frequency range by acting
Upon the control voltage from other modifiers in the synth. This enables modification of the frequency to be made by any other module that outputs some form of control voltage.
In subtractive synthesis, describe the function of the resonance control in a low-pass filter.
The resonance control allows frequencies at the cut off point to be boosted or cut. Boosting sub sonic frequency resonance can produce a truly room (and speaker cone) shattering result.
Describe three common ways an LFO might be used in analogue synthesis. Include references to other components of analogue synthesizers. Do not use abbreviations in your answer.
The Low Frequency Oscillator may be set to sine wave and may be connected to the control voltage input of the Voltage Controlled Filter via the Modulation potentiometer. When the Modulation Potentiometer is raised it will send the output to the Voltage Controlled Filter and cause the frequency band pass to be altered. This will provide a way of putting expression in the sound and works best when added to sustained notes.
Give four terms used in FM (Frequency Modulation) synthesis and not in analogue synthesis.
Operator, Carrier, Algorithm, Modulator.
Describe the waveform source in a wavetable synthesiser.
The source is from a wavetable of digital algorithms.
What technical problem would you expect to encounter when using an old analogue synthesizer for a lengthy live performance, even if the synthesizer is working to its original specifications?
Tuning drift due to temperature change.
What would be the effect of modulating the VCF of an analogue synthesizer with the LFO?
It would cause the filter to sweep in time with the LFO.
On the ADSR of an analogue synthesizer, how would you make a note decay to complete silence, no matter how long the key is pressed?
Turn the sustain right down and just work the envelope generator as an AD generator.
In an FM synthesizer, how would you quickly make a major (but probably random) change in the sound produced?
Select a different operator algorithm.
In an FM synthesizer, what would you adjust to change the high frequency content of a sound?
Digital controlled filter.
Which would you expect to sound best on an FM synthesizer: a tinkly electric piano sound or an imitation of string instruments?
Tinkly electric piano sound
Describe how frequency modulation can be achieved with a traditional analogue synthesizer, or modern equivalent. How will the end result differ compared to an FM synthesizer?
Use a number of VCOs interacting with each other, mixing different types of
waves and running them through an LFO, making an artificial algorithm. I think
that the difference will be that the sounds will not vary much from an
unmodulated, because the sound would not be altered as severely. |
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Thu Apr 29, 2004 1:48 am |
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