I use D'Addario Phosphor Bronze Mediums(13-56)on my OOOO made by Ivon Schmukler for me in '74. When I received the instrument from him, he instructed me to string it up with HEAVY GAUGE(14-58)for the 1st couple of months to break in the guitar. I have tried using light gauge on it when it was in need of a neck reset (since done by Ivon), but it doesn't sound like the same instrument. I'll stick with the medium gauge.

Mark Ross