According to the list that I rely on (www.drrick.com/conn.html) Your sax is a 1923 Conn New Wonder Series I tenor. These horns were available in both hi pitch and low pitch, so first of all, I would check to make certain that your instrument is low pitch. Below the serial number and patent date should be either a letter "L" or a letter "H". The H would indicate hi pitch, the L would indicate low pitch. Low pitch is the standard that is still used today. It's nearly impossible to make a hi pitch horn play in tune. Lets hope that it is low pitch, otherwise what you have might make a nice lamp or wallpiece. As sax maniac said, with the Conn saxophones; especially the earlier ones, you need a mouthpiece with a fairly open chamber. I would suggest an Otto Link Tone Edge (hard rubber) or a Super Tone Master maybe. I would take it to a technition and have him check it out. Maybe he might have some ideas.