Oberheim OB-Xa
| OB-Xa | |
|---|---|
| Manufacturer | Oberheim |
| Dates | 1980 - 1982 |
| Price | US$4595 - US$5595 |
| Technical specifications | |
| Polyphony | 4, 6 or 8 voices |
| Timbrality | Bitimbral |
| Oscillator | 2 VCOs per voice |
| LFO | 2 |
| Synthesis type | Analog Subtractive |
| Filter | Switchable 12dB/oct and 24dB/oct resonant low-pass |
| Attenuator | 2 x ADSR; one for VCF, one for VCA |
| Aftertouch | No |
| Velocity sensitive | No |
| Memory | 32 - 120 patches |
| Effects | None |
| Input/output | |
| Keyboard | 61-key |
| Left-hand control | Pitch Modulation |
| External control | Oberheim system |
The Oberheim OB-Xa was Oberheim's overhaul of their first compact synthesizer, the OB-X.[1][2]
The OB-Xa was released in December 1980, a year after the OB-X was released. Instead of discrete circuits for oscillators and filters, the OB-Xa (and the Oberheim synths to follow) switched to Curtis integrated circuits. This made the inside of the synth less cluttered, reducing the labor required to replace bad parts, and reducing the cost of manufacture. However, today it's much easier to fix an OB-X than an OB-Xa, as Curtis parts are getting scarcer, whereas discrete parts used in the OB-X are almost always readily available.
Aside from hardware changes, the OB-Xa had better interface features than the OB-X. These included being able to split the keyboard into two halves with different voices and the ability to layer voices to create thicker sound (essentially making two notes sound for every key pressed). Polyphony stayed the same - again 4, 6 and 8-voice models were offered.
One function that did disappear from the OB-X voice architecture was cross modulation, or frequency modulation of the first VCO with the second VCO. When done with analogue circuits, it's a unique sound made famous by the Sequential Circuits Prophet 5 and its poly-mod section. The lack of this feature somewhat reduced the range of sounds possible on the OB-Xa.
Albums that feature the OB-Xa
- Van Halen - 1984 (1984)
- Laurie Anderson - Big Science (1982)
- Miles Davis - Star People (1983)
- Bon Jovi - Bon Jovi (1984)
- Miles Davis - Decoy (1984)
- Miles Davis - You're Under Arrest (1985)
- Paul Davis - Cool Night (1981)
- Electric Light Orchestra - Time (1981)
- Electric Light Orchestra - Secret Messages (1983)
- Endgames - Building Beauty (1983)
- Brad Fiedel - The Terminator - Soundtrack (1984)
- F. R. David - Words (1982)
- Jean Michel Jarre - The Concerts in China (1982)
- Jean Michel Jarre - Zoolook (1984)
- Chaka Khan - I Feel for You (1984)
- Evelyn King - Get Loose (1982)[3]
- Mezzoforte - Surprise Surprise (1982)
- Naked Eyes - Burning Bridges (1983)
- Stevie Nicks - The Wild Heart (1983)
- Gary Numan - Warriors (1983)
- Mike Oldfield - Crises (1983)
- Mike Oldfield - Discovery (1984)
- Mike Oldfield - The Killing Fields - Soundtrack (1984)
- Prince - 1999 (1982)
- Prince - Purple Rain (1984)
- Queen - Hot Space (1982)
- Queen - The Works (1984)
- Rush - Grace Under Pressure (1984)
- Rush - Moving Pictures (1981)
- Rush - Signals (1982)
- Scandal - Goodbye to You (1982)
- Silent Running - Shades of Liberty (1984)
- Simple Minds - New Gold Dream (81/82/83/84) (1982)
- Simple Minds - Sparkle in the Rain (1984)
- Styx - Kilroy Was Here (1983)
- Talk Talk - The Party's Over (1982)
- The Police - Ghost in the Machine (1981)
- The System - Sweat (1983)
- The Stranglers - Feline (1983)
- The Stranglers - Aural Sculpture (1984)
- The Thompson Twins - Into the Gap (1984)
- The Thompson Twins - Quick Step and Side Kick (1983)
- Paul Young - No Parlez (1983)
- Paul Young - The Secret of Association (1985)
