The positioning guidelines found here will work well for most guitars.
On arched-back guitars like Taylors and specifically the GS Mini, these guidelines may not allow for TWA to function optimally. You should test for areas that offer the most contact to the suction liners and transducer cone.
While we do recommend positioning the ToneWoodAmp along the center line of your guitar, offsetting the TWA from the center line of the guitar is acceptable to maximize contact with arched back or smaller-bodied guitars.
Remember, the placement guidelines are just guidelines. Spend some time experimenting with your TWA in different locations during the dry fit process detailed in the Positioning the ToneWoodAmp section of our video manual.