Not much difference, just slightly more open facing on a C** I believe. but this might be very slight which means you could simply change to a slightly harder reed and have similar results so don’t get hung up on choosing between these two mp models. whoever told you that one is for classical and the other for jazz does not know what they are talking about. the baffgle is the same on those which is no, or low baffle as opposed to a high baffle which is what is going to give you a louder, brighter sound. the low/no baffle means a darker sound which is preferred by classical people but both the C* and C** have that. Yes you can use a C** for any type of music you want to play.
These mp models are very good, especially for starting out. Most players will move on to other models because these two have a smaller tip opening (facing) and to get a bigger and fuller sound you’ll eventually want to try something bigger.
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