From the Ortofon website:
2M Series styli interchangeability:
The 2M Series' engines, coils and magnets configurations are not identical: Red and Blue are identical, so are the Bronze and Black and so are the true mono variants 2M Mono and 2M 78. Likewise, 2M series styli are interchangeable within the below combinations:
- 2M Red, 2M Blue and 2M Silver
- 2M Bronze, 2M Black and 2m Black LVB 250
- 2M Mono and 2M 78
I know what the website says. It's a marketing gimmick It is a fact that ANY 2M stylus will fit ANY 2M body. For example, an LVB Black stylus on a Red body will fit, and it will work, just not as well as the more expensive generator would let it, and it would definitely be out of place. Ortofon wants people to think it CAN'T be done, to prevent them from putting a Bronze/Black stylus on a Red/Blue body. They'd rather you pay the extra $80-100ish dollars for the upgrade body. And they're right, why would you buy a race-horse, and then not let it run? But, the truth is somewhat different.
A close friend is an authorized Ortofon dealer. He has called Ortofon-USA while I was present, and asked them this exact question, and relayed their response. And, as I have the Red, Blue, and Bronze, I've actually done the experiments. Surprisingly enough, my records didn't melt, the stylus didn't fall off, and the cantilever didn't bend like one of Uri Geller's silver spoons. The ONLY thing that happened was that the Bronze stylus on the Red generator didn't sound as detailed, open, or airy. It seemed rather constricted. However, the Blue stylus on the Bronze body actually has a more pleasant presentation than with the correct lower-tier generator. In THIS configuration. the performance gap between the Blue and Bronze styli shrinks noticeably. That's not to say they're equal, because they're not. The Bronze is still way better.