I have got a few old alto's, the oldest is a 1927 buescher true tone and i use a metal berg larson. I dont hold with the theory about you have to use a vintage mpc on a vintage horn. If its set up correctly you can use what you want. The only ones that are a bit picky are the conn 10m tenors which seem to prefer a larger chamber mpc. I have one and 2 chu's and the chu's aren't picky whereas the 10m is slightly picky Dave