CV-13

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There are some videos with descriptions at the auction.

"Combines Features of the Roland BC-13 with Control Voltage Conversion for ALL Vintage GR Controls. Works with Roland G-202, 303, 505, 707, 808, Ibanez IMG2010 and Roland GI-10, GI-20, GR-1, GR-9, GR-30, GR-33, VG-88, VG-99 and More!

Features of the CV-13:
* Converts Vintage Roland 24-pin GR Signals to Modern 13-pin Signals
* Four top panel foot switch controls for Synthesizer Volume, Filter, Resonance and Guitar Mute
* Up to FIVE simultaneous control voltage outputs in Roland EV-5 standard
* Six internal precision Phifer cermet trimmers to adjust response range
* Rear panel EV-5 volume pedal input for direct guitar signal
* Bi-directional support for Ibanez IMG2010 virtual whammy bar
* "Pin-9 to Ground" switch to reduce grounding issues with Roland synthesizers
* Powered by 13-Pin Guitar Cable! No External Power Supply or Batteries Required
* Solid oiled walnut sides on a black, ventilated steel base with contempra grey (beige) aluminum top panel, 280 mm x 220 mm x 100 mm.
* Backed by One-Year Parts and Labor Warranty
* Elegant Design

The onboard controllers that made the early Roland synths so much fun to play disappeared when Roland switched from the 24-pin design to 13-pin design. While Roland has continued to dramatically advance their guitar synthesizer design, modern 13-pin systems are still limited compared to their 24-pin predecessors. Realizing that guitar players wanted more control options, Roland added both a D Beam controller and Ribbon Controller to the new VG-99. These options are great, but they are not as convenient as the vintage 24-pin onboard controllers. And the D Beam and Ribbon controllers require the guitar player to be relatively near the VG-99.

The new CV-13 completely bridges the gap between a vintage 24-pin guitar controller and the VG-99/FC-300 combination. How? The VG-99 has an EV-5 control pedal input on the back, plus there are three EV-5 inputs on the FC-300, making a total of four continuous control inputs to the VG-99/FC-300 combination. With a Roland G-303 and the CV-13, for example, and you can use the filter, resonance, vibrato, and balance controls on the guitar to operate the VG-99. The virtual GR-300 in the VG-99 can now work exactly like a real GR-300, with the player adjusting GR-300 parameters from the guitar!

But this is just the beginning! The CV-13 also supports the virtual whammy bar found on the super-cool Ibanez IMG2010. And the CV-13 provides two whammy bar outputs, one control signal for moving the bar up, and one for moving the bar down! While recreating a virtual GR-300 was the initial inspiration for the CV-13, so much more is possible! The VG-99 has over 4000 target parameters, and any of these can be assigned any controller on a vintage 24-pin guitar. Or the guitar controllers can be assigned to continuous MIDI controllers, for manipulating soft synths in real time!

This setup requires several TRS cables from the CV-13 to the VG-99/FC-300 EV-5 inputs. For this reason, the CV-13 package also includes one 12’ TRS cable and three 3’ TRS cables. These are brand new, high-quality cables from Orange Country Speaker, specially modified for the VG-99/FC-300."

Auction videos minus the descriptions here. Also check out the BX-13 here, and the DC-13 here.