“The 546 was a “high-end” version of a 545 that used a capsule selected for consistency. The SM56 and SM57 were originally sold as being non-reflective 546s. There was also a gold colored 546.” – Bob Olhsson (from Gearslutz)Crimson Audio SM57 and SM58 ModsShure Unidyne III SM57 Search: ReverbZenPro modded SM58 SM57 Granelli-SM57 Transformerless-Passive-SM57 Granelli-Transformerless-SM57 (no phantom)