As soon as people learned how to record sounds, so came the idea of a device that reproduces the sound of notes recorded from various musical instruments. The first attempts to create something like a synthesizer were made back in the days when sound was recorded on wax cylinders. But such devices could not be used in practice because the mechanics were too complicated and unreliable and the sound quality was far from satisfactory.
The first mass-produced synthesizers were electronic, producing sounds synthesized by sound generators that were only remotely similar to the sound of real instruments. However, the bandstand, which was in its heyday, liked “electronic” music.
Author: musician Кирилл Юровский.
Sampler synthesizers, capable of replacing a real instrument, appeared only in the 1970s, were very expensive, and were used mostly in the studio. Only in recent decades have digital music and the development of microelectronics made sampler synthesizers available to everyone – now at the touch of a button a musician can switch from guitar to organ, from toonily flute to drums, or synthesize sounds unplayable by any real instrument.
Today, synthesizers are made in a wide range of products and are used for a variety of purposes:
- As musical toys;
- For learning music and playing the piano;
- For home concerts;
- For professional concert activities;
- For studio work in creating and recording music.
All of these areas have different demands on the instrument, and to make the right choice, you need to understand what you need the synthesizer for and what features are important in your particular case.
The size of the keys is one of the first parameters that determine the “maturity” of an instrument. Full-size keys correspond to the keys of an ordinary (acoustic) piano. There are models with smaller keys – they are more compact and cheaper, they are often taken for children. But it would be a mistake to use such a model for learning. Learning to play a complete piano or a professional synthesizer is tightly connected with the development of motor skills – the fingers have to “get used” to the size of the keyboard and the distance between the keys. Therefore, small keys are not suitable for learning or even more so for professional activities.
It is a good idea to use small keyboards as a toy to familiarize yourself with music and musical instruments for the first time. But even for the very first lessons of learning to play the synthesizer, you should use instruments with full-size keys.
The number of keys on a synthesizer determines the width of the sound range – the number of octaves available to the musician at the same time. The classical piano keyboard contains 88 keys (7 full octaves + 3 sub-octave keys). But most of the time, it is rare that you play a full seven-octave range at the same time, so you don’t use the full 7-octave keyboard very often. This keyboard is used on models that are used as an alternative to the piano, as well as on digital pianos themselves.
On synthesizers, shortened keyboards with fewer octaves are most common: 6, 5, or even less.
It should be understood that a smaller number of octaves does not necessarily mean that some octaves are not available to the musician – the presence of transposition on a synthesizer allows you to “shift” the sound range relative to the keyboard. For example, a 5-octave synthesizer with two-octave transposition (24 semitones), can be configured to play from the check-octave to the second, as well as from the minor to the fourth. With such shortened keyboards, the musician still has access to the entire sound range, but not all at once.
What size keyboard you should use depends on the purpose of the instrument. Complex classical pieces require a 76-key keyboard, while 5 octaves (61 keys) are sufficient for most popular tunes.
Synthesizers with less than 5 octaves are already considerably limiting possibilities of a musician but they can be used professionally too – for example for imitation of any real instrument with a not so wide sound range (trumpet, drum, oboe and so on). But it would be very difficult to play on such a keyboard with two hands.
Polyphony determines how many individual tones can be played simultaneously. Although chords of more than six tones are rarely found in music, this does not mean that a polyphony of 8 voices is sufficient. A picked up sound does not subside instantly, and a Synthesizer with 8-voice polyphony will inevitably get “choked up” when a new sound is picked up.
Even for “pure” playing without sound effects, a polyphony of 32 voices is recommended.
To use sound effects, Auto Accompaniment or Arpeggiator, you need 48-64 voices.
To take full advantage of the Synthesizer’s capabilities – with sound effects, multiple layering of soundtracks, etc., you need a polyphony of 72-128 voices.
The key mechanism is characterized by several indicators that are often confused with each other. At the same time, there is nothing complicated here – by the type of mechanics keys can be synth, piano or hammer. In terms of hardness – unweighted, semi-weighted and weighted. And by sensitivity to velocity of pressure – active (dynamic) and passive (non-dynamic).
Types of Key Mechanics
Synthesizer keys are ordinary electric keys that return to their original position by the action of a spring. These keys are easy to make and inexpensive, but they have an uninformative response when pressed. The volume and duration of each tone depend on the speed and force with which the key is pressed. The informative nature of a key means that it reacts differently to presses of different speeds and strengths. Non-informative synth keys, on the other hand, do not allow the performer to proportion the effort of pressing with his fingers and are not suitable for professional use.
Piano keys contain a complex spring mechanism that mimics the resistance that occurs when a piano key is pressed. There are various versions of piano mechanisms, from simple ones containing 2-3 plastic parts to complex ones with several levers and springs, structurally similar to hammer-type mechanisms. Accordingly, the response on pressing the key can be different in terms of comfort and informative – both “not far gone” from the synthesizers, and close to the “real” piano.
Hammer keys contain a hammer mechanism, similar to the one used in acoustic pianos, but adapted for use with electronics. Such keys provide a tactile experience as close as possible to the “real” experience of playing an acoustic piano. But hammer keys increase the size of the instrument and are expensive, so they are installed only on digital pianos and on some professional models of synthesizers.
Key stiffness types
Unweighted keys are easy to press and have minimal pressure resistance. These keys are installed on toy synthesizers.
Semi-weighted keys are stiffer and provide better pressure control. Most amateur models and some professional ones use semi-weighted keys.
Weighted keys have the same stiffness as an acoustic piano key. These keys are used on professional models. Sometimes weighted keys are confused with hammer keys, but such correspondence is not entirely correct. There are quite a few spring piano mechanisms that provide “weighted” rigidity. All hammer keys are weighted keys, but not all weighted keys are hammer keys.
Speed sensitivity allows the synthesizer to change the character of the sound depending on how fast (force) the key was pressed. On most musical instruments, the louder the sound, the more effort you apply. This is an important condition for a “live” sound. Therefore, a synthesizer with passive (speed-insensitive) keys will sound “dead”, no matter how skilled the musician is. Passive keys are appropriate only for toys and educational models of the entry level. Professional models are not just equipped with active (dynamic) keys – their sensitivity has hundreds of gradations.
The total number of tones determines the variety of sounds and musical instruments “living” in the synthesizer. Each tone (sample) corresponds to an instrument. Accordingly, the more timbres you have, the more choices you have. How many timbres you choose depends on what you want to use the instrument for.
Professional digital pianos often have no more than a dozen tones (and those are the different piano variations), and that’s good enough for them. For studio work – the more the better, professional models can have thousands of built-in timbres, plus the ability to record new ones. Children’s models can also have dozens or even hundreds of tones, including very exotic ones like train noises or birdsong.
Auto Accompaniment lets you play a tune in the background while you play. This makes it easy for even beginner musicians to play a decent-sounding improvisation on any theme (as long as the available Auto Accompaniment styles provide for it). And while serious performers are dismissive of this feature, for the novice musician, Auto Accompaniment can make it easier to accompany an event with music.
The arpeggiator is a function somewhat similar to auto accompaniment, but not as lazy. The arpeggiator lets you play a predetermined sequence of notes (“chorus”) literally by pressing a single key, and the arpeggio tone can change depending on which key is pressed.
The sequencer allows you to record your own music for later playback in the background. This is again similar to Auto Accompaniment, but with the difference that in this case you create the accompaniment music yourself. In addition, multitrack sequencers allow you to overlay multiple soundtracks created by the sound of different instruments. This allows you to create musical compositions that would require an entire orchestra to actually record them. Studio workstations necessarily have a multitrack sequencer.
Professional models with a sequencer have an individual audio output for each track, so they can be mixed on the recording equipment.
Sampling is also a very important feature for a studio instrument. Sampling allows you to independently record new tones (samples) for later use.
Note the analog and digital connectors on the synthesizer. The line and microphone inputs allow you to run an external sound signal through the synthesizer, with overlays of selected sound effects, which can greatly enrich the DJ or soloist’s abilities. The headphone output lets you fully practice with the synthesizer without disturbing those around you with loud sounds.
For a studio instrument, it’s almost essential to have digital outputs (USB or MIDI) on it for communication with a computer. Not only will this greatly expand your ability to process sound and create new compositions, but it can also lower the price of the instrument by transferring some functions to your computer. For example, a multitrack sequencer with individual outputs raises the price of the synthesizer considerably. At the same time, you can also achieve the desired effect on a synthesizer without a sequencer at all by recording the sounds of the various instruments to the computer through a digital interface and combining them using a software sequencer. It takes more time and requires more skill, but the end result will be no worse than if you use an expensive synthesizer.
The learning features are great for the aspiring musician. A rhythm-setting metronome also comes in handy when learning.
The learning mode available on backlit keyboards is very effective.
In learning mode, the keys are illuminated at the same time as the corresponding notes are displayed on the LCD. This lets you quickly learn which keys correspond to which notes, so you can acquire the appropriate motor skills. Text from here