Hello! I'm hoping someone can help me in this search for info on a Gibson mandolin. This photo was in the booklet from the Beach Boys "Pet Sounds Sessions" box set. Barney Kessel is holding what looks like a Gibson mandolin with 12 strings, and the instrument appears to be acoustic since a microphone is placed near the F hole just at the bottom of the shot and I see no signs of a pickup. I have found little information on this instrument other than this photo, and I've been looking for other photos and answers for years.
Was this a production model Gibson that would have been in their catalog, or was this a custom order for Barney, or even another session musician? Was this instrument electric, or acoustic? What year or era does it appear to be by the features shown in the photo? The only guess I can offer is that it may be closer to a Vox Mandoguitar, where it is tuned like a guitar but strung in pairs like a mandolin minus the octave strings of a normal 12-string.
Thank you in advance for any help or info, as this info could help settle a lot of questions and discussions. Specifically, one of them is whether this very instrument could have been used by Barney to play the intro to "Wouldn't It Be Nice" on Pet Sounds.