A small group on the saxophone acoustics forum is embarking on a study to compare the intonation tendencies of different mouthpiece shapes and designs. It is understood that for a saxophone to play properly the equivalent volume* of a mouthpiece must come close to matching that of the missing cone. Some mouthpieces are shorter and have larger chambers, while others are longer and have more narrow chambers. So there are different ways that mouthpieces can have the same volume required to match that of the missing cone. The essential question is whether the long and narrow mouthpiece and the short and fat mouthpiece both play in tune in all registers and whether their harmonics differ in some way. Anyone who has any experience of one mouthpiece being more in tune than another on their saxophone is invited to give input in this thread. The brand and number (facing) of the mouthpiece(s) and the type (SATB), make, and model of the saxophone along with a description of your experience would be very helpful. Thanks. Of course anyone is welcome to joint the forum and participate there as well. * The equivalent volume is the geometric volume of the inside of the mouthpiece plus the volume added by the travel of the reed and the effects of the player's oral cavity.