The Siel Orchestra is an analogue subtractive synthesizer, which was produced by Italian manufacturer Siel from 1979 to 1982. The original Orchestra was very limited but still a very characteristic instrument for its time. It produces its sounds from a divide-down oscillator network and therefore has 49 note (unlimited) polyphony. Although it contains 4 sections of presets (Brass, Strings, Reed and Piano), each which contain two sounds, the only parameters that can be edited are Vibrato (LFO), Brilliance (for the Brass, which also has a separate 'Brass Attack'), Attack and Decay. This ultimately means that the Orchestra cannot produce many different sounds; however because of its Italian origin and its distinctive routing, the Orchestra sound is not matched by any other similar synthesizers.
| Quartet | |
|---|---|
 ARP Quartet | |
| Manufacturer | ARP Instruments, Inc. |
| Dates | 1979 - 1980 |
| Technical specifications | |
| Polyphony | 49 |
| Timbrality | 1-2 |
| Oscillator | 1-2 of 4 |
| LFO | 1 |
| Synthesis type | Analog Subtractive |
| Filter | 4-pole |
| Attenuator | AS (brass & string) |
| Storage memory | 4 |
| Input/output | |
| Keyboard | 49-key |
| Left-hand control | none |
| External control | none |
The Orchestra was later bought by ARP Instruments to be slightly modified, relabeled and then sold as the ARP Quartet. This version replaced the Reed section with an Organ one; however, aside from that the synthesizer was almost identical.
The Orchestra does not support MIDI or any other means of communicating with other electronic instruments; however, it does include a volume pedal socket which could be mistaken for a MIDI port.
Orchestra 2
Later, a more programmable version of the Orchestra was released. It still used 4 preset sections; however, it offered many improvements over the original version. A better filter for the brass section was included and more sounds were added to other sections. It also introduced a very simple LFO, a graphic equalizer, octave transposition and an 'animator section' which was effectively a flange effect. It also had a pitch bend function which was surprisingly never included with the first version Orchestra.