This has been borne out by acoustical experiments done by Walter Lawson on french hor Jeff Stockham puts it well describing his 1959 10B Victor: The copper bell also adds projection. It is generally accepted that high(er) copper content bells make the sound'darker' and have better projection. According to Conn, Coprion has a special characteristic which permits great dynamic range without change in tone color. The brass bell showed an'irregular and hodge podge' crystal structure with comparatively large crystals, while the Coprion bell showed'ions of pure copper side by side in regular, close knit conformation and at right angles to the surface of the metal' What does Coprion do to the sound and the way the instrument plays? It is said that on an instrument with a Coprion bell'you can't overblow or'crack' a note. Conn showed diagrams of the structure of'ordinary' brass bells compared to the Coprion bell. Coprion isn't the same as a'rose brass' or'red brass' bell these are brass bells with a higher copper content.

It consists of electrolytically depositing COPper IONns(hence the name Coprion) onto a stainless steel precision form accurate to millionths of an inch(so Conn said in its 1959 catalog) Creating a seamless bell. Valves and slides are quick and free, good compression and a period case is included(one missing latch) What Conn Said about the Coprion Bell: What is Coprion? The process necessary for producing the Coprion bell was developed by Conn in 1938. Use a deep Mouthpiece for darker sounds, or a shallower one for a lead horn sound. more This is a large bore, 484' horn that is great for beginners, come back players or pros that want that occasional jazzy, dark sound. Smokey sound that the Conn Coprion Bell affords. Conn 17a Coprion Bell Cornet Raw Brass& Copper Finish Has that great cornet sound with the mellow.

1963 conn trumpet serial numbers