The Goto SG-505TT is a low midrange driver. The 50mm diameter diaphragm is made of titanium with a FRP surround. Magnetic circuit uses a 130mm diameter ALNICO magnet and Permendur. The audible result is solid sound with further improved definition and clarity. Throat diameter is 30mm.

SG-505DX has a larger (140mm) and stronger magnet.

Three types of hyperbolic horns can be fitted on these drivers : S-150B, S- 200B and S-300B.