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1、The Audio Playground Synthesizer Museums PDF Library. All text and graphics are property of their corresponding manufactures. Remade for historical purposes. RadioFans.CN 收音机爱 好者资料库 RadioFans.CN 收音机爱 好者资料库 WHAT IS HUMAN ENGINEERING? Human engineering is the least talked-about aspect of synthesizer d
2、esign. It is also the most important. Human engineering determines what your synthesizer will look like, where the knobs will be placed, what color to make the switches, what typeface to use for panel graphics. how far the keys must be depressed, and dozens of other considerations. At ARP, we make a
3、 big deal about human engineering. Because designing a perfect synthesizer requires much more than perfect oscillators and filters-it requires a sensitivity for how an instru- ment should be shaped and structured so that it feels good in your hands. “Human Engineering” involves getting lots of perfo
4、rming musicians involved in the actual conceptual design process. The success of the process is crucial. A bunch of engineers sitting around a drafting table can come up with a synthesizer loaded with gadgets that are impossi- ble to play! The biggest mistake you can make when purchasing a synthesiz
5、er is to be lured by the lists showing how many oscillators, filters, etc., a synthesizer contains. You need a synthesizer that feels right to you. And unless youre planning on disappearing into a laboratory, you need a synthesizer that is human engineered. As Michael Brooks said in Creem magazine,
6、“For a brief analysis, Moog, like Kleenex and Coca-Cola. is the name most commonly used to explain synthesizers, but ARP is the most popularly used synthesiz- er in rock. The ARP was aimed at the working musician, working musicians like Elton John, Beach Boys, N. Y. Rock Ensemble, Herbie Hancock, th
7、e Rascals. Grateful Dead. Frank Zappa, Jefferson Airplane, Chicago. Seatrain, John Lennon, Led Zeppelin, Miles Davis. Al Kooper, The James Gang. Santana, Three Dog Night, Sly and the Family Stone, Stevie Wonder, Peter Townshend, and on and on.” * _ *Creem, May 1973, Vol. 4, No. 12, p. 73. The bigges
8、t mistake you can make when purchasing a synthe- sizer is to be lured by the lists showing how many oscilla- tors, filters, etc., a synthesizer contains. RadioFans.CN 收音机爱 好者资料库 The less glamourous aspects of synthesiz- ers, like where cer- tain knobs are placed on the panel can be much more importa
9、nt to a musi- cian than how many oscillators or ring modulators he has. LETS TALK FUNCTIONS Oscillators, Filters. Envelope Generators, Ring Modulators. and other wonderful devices all make up the “Functions” in a synthesiz- er. Ever since synthesizers were invented, manufacturers, including us, have
10、 run around with charts proving how many “Functions” their synthe- sizers had. We now know that less glamourous aspects of synthesizers, like where certain knobs are placed on the panel, can be much more important to a musician than how many oscillators or ring modulators he has. So instead of just
11、counting functions, lets talk about what these func- tions do for you. Because if you want to synthesize your way to star- dom, youre going to have to do it with sounds. not figures. In the following pages. were going to compare the ARP Odyssey with three other synthesizers in a comparable price ran
12、ge. What we prove in this comparison is what most of the worlds most famous synthesizer players already know that the ARP Odyssey is the synthesizer designed by musicians for musicians. FIRST A LITTLE THEORY All the functions on a synthesizer can be divided into three categories: 1). Sound Sources.
13、Includes oscillators and noise generators. 2). Sound Modifiers. Includes Filters, ring modulators, etc. 3). Controllers. Includes keyboards, foot pedals. envelope generators. The “raw” sounds from the oscillators or tone generators are “processed” through the Sound Modifiers like the filter or ring
14、modulator. Controllers are hooked up to both the Sound Generator functions and Sound Modifier functions so that the performer can change or control the sounds being produced. Thats all there is to it! 2 AUDIO OSCILLATORS The audio oscillators are the basic tone sources in any synthe- sizer. As you p
15、lay up and down the keyboard, the oscillators will follow the notes. The oscillators do not have to be set for the same pitch. If you tune two oscillators to an interval. you can play that interval up and down the scales. OSCILLATOR WAVEFORMS The waveforms produced by oscillators determine the overa
16、ll limitations of a synthesizer. Each different kind of waveform contains different harmonics and has a different sound. By filtering, you will be able to remove certain harmonics and change the sound somewhat. Since you can never add har- monics, the oscillator waveform will determine the general o
17、verall quality of the sound produced. Waveforms are either Static or Dynamic. A static waveform is simply a steady, unchanging tone. A dynamic waveform is one which changes during the sound. If you looked at the wave- forms from conventional instruments, like guitars or pianos. you would see that th
18、e waveforms are not constant. but are always changing as the tone dies away. The most common synthesizer waveforms are: Sawtooth static Brassy Square static Hollow. clarinet-like Pulse static Bright, reedy Modulated pulse dynamic Rich, chorus-like Phase-sync sawtooth dynamic Voice-like, wide range S
19、ine static Pure colorless tone, contains no harmonics The Odyssey is the only synthesizer in this comparison with dynamic waveforms. Both of the two audio oscillators in the Odyssey will produce all the common static waveforms as well as a modulated pulse wave and phase-synchronized wave. The Odysse
20、ys filter can be used as a third oscillator and gen- erates a sine wave output. The Odyssey is the only synthesiz- er that can produce a truly pure sine wave. The Minimoog has three oscillators. None of its waveforms, however. are dynamic. The waveforms include sawtooth. square. and pulse waves. The
21、 triangle wave has the same overtones as a square wave, but is not as bright. A “Reverse Sawtooth” sounds exactly the same as a regular sawtooth. Only the Odyssey gives you 2 dynamic wave- forms for rich, complex sounds, and a sine wave for pure tones. The Sonic VI has only two voltage controlled os
22、cillators, neither of which can produce dynamic waveforms. The EML-101 has four oscillators. This synthesizer creates six wave- forms, all static. However, out of that six. the square wave. “sloped square” wave and triangle wave all have the same harmonics, the only difference being brightness. In a
23、ddition, as with the Minimoog. the invert- ed sawtooth wave is identical to a regular sawtooth wave in sound. NUMBER OF OSCILLATORS Generally. more oscillators means a richer, more chorus like sound. However, the effectiveness of an oscillator depends on the variety of waveforms the oscillator can p
24、roduce. For instance. one oscillator with dynamic waveforms can produce richer sounds than two or three oscilla- tors with static waveforms only. If a synthesizer is equipped with a two- voice keyboard, then you obviously need at least two oscillators in order to produce two-note chords. Because bot
25、h oscillators in the ARP Odyssey have dynamic waveform outputs, the Odyssey can create sounds that are as rich as or richer than synthesizers with twice the number of static waveform oscillators. In most live performance situations, you will want to be able to add vibrato, tremelo, and other musical
26、 effects. This requires a Control Oscillator. If a synthesizer is not equipped with a special control oscilla- tor, then one of the audio oscillators must be used for this purpose. In other words, a synthesizer with three audio oscillators but no control oscillator has Iittle advantage over a synthe
27、sizer with only two oscilla- tors, since one of the three will almost always be used for making treme- los and vibratos. The Odyssey is the only synthesizer that includes a special control oscillator in addition to two audio oscillators and filter oscillator. OSCILLATOR RANGE Making an oscillator wi
28、th wide range, i.e., the ability to make a continu- ous sweep of frequency over a wide range of pitch, is the most difficult achievement in oscillator design. You will notice that on some synthesiz- ers the keyboard will go out of tune as you approach the high end, or the unit will require retuning
29、when the pitch range of the instrument is changed. OSCILLATOR STABILITY If an oscillator is not stable. your synthesizer will drift out of tune while you are playing it. To test for stability, turn Only the Odyssey gives you rock- stable oscillators that track over a wide range. 4 on a synthesizer t
30、hat has not been used for several hours and quickly pin down one note and tune to a pitch reference like an organ. As the synthesizer warms up, its pitch may drift if the oscilla- tors are not properly designed. Forget about the figures and trust your ears instead! The range of the Odyssey oscillato
31、rs is from 16 Hz to 16.000 Hz in one continuous sweep. We consider widerange drift-free oscillators a must on all our synthesizers. The range of the Minimoog oscillators is limited and must be switched in octave intervals. Check to see if these octaves are per- fect or whether they require additiona
32、l tuning. The stability of the Minimoog oscillator is specified at 1% (6% equals one semitone). AUDIO OSCILLATORS Odyssey Minimoog Sonic VI EML-101 Number 3* 3 2 4 Dynamic waveforms 2 0 0 0 Extra control oscillators 1 0 2 0 *Includes filter in self-oscillating mode KEYBOARDS The keyboard in a synthe
33、sizer performs two important functions: 1). It determines what note(s) the oscillators will play. 2). It triggers the envelope generators, which causes the attack and decay of the sound. All the compared synthesizers have keyboards of roughly the same length and have the capability of gliding (porta
34、mento) from note to note. The Odyssey is the only synthesizer which includes a foot switch to control this glide, however. All the keyboards can play two notes at a time. except for the Minimoog, and all the units have the ability to transpose the range of the keyboard. All the synthesizers have som
35、e facility for “pitch bend- ing,” but the ARP Odyssey is the only synthesizer that includes a foot pedal for pitch bending. Pressing a note on the keyboard of any synthesizer will trigger the envelope generator. However, pressing down a second note will not trigger the envelope generators on any of
36、the instruments except the ARP Odyssey. This means Only the Odyssey includes foot pedal- controlled glide and pitch bend. 5 that in order to get clean attacks and decays, you have to lift your fin- gers off the keyboard inbetween notes. On the Odyssey, you can run notes together and never miss an at
37、tack because of the Odysseys “multiple triggering” feature. KEYBOARDS Odyssey Minimoog Sonic VI EML-101 Keys 37 44 49 44 Polyphonic yes no yes yes Multiple triggering yes no no no Foot pedals included yes no no no VOLTAGE CONTROLLED FILTER The voltage controlled filter is the most important modifyin
38、g function in the synthesizer. The characteristics of the voltage controlled filter have an overall effect on the “sound” of a synthesizer. A filter is used to eliminate certain harmonics or frequencies from a sound. The most common types of filters are: 1). Low pass filter: Removes high frequencies
39、, making the sound muffled or dull. 2). High pass filter: Removes bass frequencies.making the sound very raspy and thin. 3). Band pass filter: This filter eliminates all but a narrow band of frequencies. The most useful filters are the low-pass and the band-pass filters, because most natural instrum
40、ents are low-pass and band-pass filters. All instrumental sounds and most “electronic” sounds are created using these filters. All the synthesizers discussed here have one volt- age controlled filter which can be either a low-pass or band-pass filter. The filter on the EML-101 has a high-pass output
41、 in addition. And the ARP Odyssey has a separate manual high-pass filter. FOOT PEDAL CONTROL The ARP Odyssey is the only synthesizer which includes a foot pedal filter control When the filter is being used as a low-pass filter. this pedal controls the brightness of the sounds. When the filter is bei
42、ng used as a band-pass filter, then the pedal acts like a wa-wa effect. Multiple triggering keyboard is an Odyssey exclusive. Only the Odyssey includes foot pedal control for live per- formance control of the filter. 6 FILTER CUTOFF CHARACTERISTICS Cutoff characteristics determine the “sound” of you
43、r filter. Expressed in dB/octave, this figure tells you how effectively the filter eliminates sounds that it is supposed to filter out. The higher the figure, the greater the filtering effect. The Odyssey and the EML-101 have 12 dB/oct filters. The Minimoog and Sonic VI have 24 dB/oct filters. The 1
44、2dB/ oct fil- ter will produce better string and reed sounds, but the 24 dB/oct will create better brass and flute sounds. Big studio synthesiz- ers like the ARP 2500 offer both kinds of filtering. VOLTAGE CONTROLLED FILTER Odyssey Minimoog Sonic VI EML-101 Number 1 1 1 1 Cutoff in dB/oct 12 24 24 1
45、2 Foot pedal control yes no no no included. NOISE GENERATOR Only the EML-101 does not include both white noise and pink noise. Pink noise sounds even to the ear; white noise sounds very high-pitched and “hissy.” There is no filter on the EML-101 which can convert its white noise to pink noise. NOISE
46、 GENERATOR Odyssey Minimoog Sonic VI EML-101 White only easy-to-use slide switches are used. On all other units, patch controls are all over the panel; several different types of switches are used. COST EFFECTIVENESS You will pay for all the features on any synthesizer. even the ones youll never use
47、. Only the ARP Odyssey has been designed especially for live per- formance. On some other synthesizers, you pay for the ability to play microtonal scales. You pay for a full bank of jacks and patch cords. You pay for many features that are not generally useful to the performing musician. On the othe
48、r hand. the Odyssey includes two foot pedals especially for live performance. Only the Odyssey includes slide controls throughout for quick visual reference. Only the Odyssey includes a four-control envelope generator. And only the Odyssey includes just what you really need. without redundant or inefficient controls or superfluous features. PRICE All the synthesizers are sold t