Oberheim OB-Xa
The Oberheim OB-Xa was the second of Oberheim's OB-series polyphonic analog subtractive synthesizers, replacing the OB-X with updated features.
History
The OB-Xa was released in December 1980, replacing the OB-X after only a year on the market. The OB-Xa was the first Oberheim product adorned with blue horizontal pinstripes on black background that would become standard trade dress for future Oberheim products. While the OB-Xa offered the same polyphony as its predecessor, its keyboard could be split into two halves or to layer voices to create thicker sound. The OB-Xa also added the ability to switch between 2-pole 12 dB and 4-pole 24 dB filtering. It offered Filter Envelope modulation for oscillator 2 in place of the OB-X's ability to cross modulate.Instead of the discrete circuits for oscillators and filters utilized by the OB-X, the OB-Xa switched to Curtis integrated circuits. This made the inside of the synth less cluttered, facilitating troubleshooting, and reducing the cost of manufacture. It was getting more difficult to service the OB-Xa due to the scarcity of Curtis chips; however, Curtis in June 2016, Coolaudio and Alfa all started re-manufacturing some of these chips which has breathed new life into the longevity of the OB-Xa and many other synthesizers that use these chips.
Notable OB-Xa users
- The Carpenters
- Miles Davis
- Brad Fiedel
- Calvin Harris
- Billy Idol
- Jimmy Jam and Terry Lewis
- New Order
- Gary Numan
- The Police
- Prince
- Queen
- Robert J. Walsh
- Cliff Richard
- Rush
- Simple Minds
- Rod Stewart
- The Stranglers
- Thompson Twins
- Van Halen
Hardware re-issues and recreations
In 2017, Behringer announced it would replicate the CEM3340 VCO chips used in the OB-Xa synthesizer. The widow of chip creator Doug Curtis released a statement clarifying that the replica was made without permission and that Curtis "would be deeply saddened by the attempt of others to trade on his name and to make unsubstantiated claims of equivalency to his original inventions". In 2018, Uli Behringer announced that Behringer would be producing a clone of the OB-Xa known as the UB-Xa, but a microprocessor shortage delayed the project. The following year, however, Behringer announced that the UB-Xa was ready for manufacture, and announced a desktop version. The first UB-Xa units were delivered in December 2023.In May 2022, the Oberheim OB-X8, a new 8-voice analog synthesizer with the voice architecture and filters of four classic Oberheim models: the OB-X, OB-SX, OB-Xa, and OB-8, along with functionality and features not included on the original models, was announced. The new synthesizer is manufactured by Sequential in partnership with Tom Oberheim.