Our current six-string guitars are strung with D'Addario EXP16 strings. They're a light gauge (12s) phosphor bronze-coated series set.
Future guitars will use the new D'Addario XS light gauge phosphor-bronze strings.
The Algonquin 12 is strung with D'Addario EJ38 light gauge (10-47) phosphor bronze strings.
Most of our guitars can handle slightly heavier gauge strings, but the nut may have to be re-filed to widen some slots. Changing the string gauge can also affect neck relief, which could necessitate a slight turn of the truss rod.
If you add medium gauge strings to the Algonquin 12, we recommend tuning it down a tone and evaluating how the top of the guitar responds over a few weeks before tuning up to standard pitch.