The ideal drum is a 45 gallon oil drum of 18 gauge metal. For the best results the rims should ideally be flat although round rims are acceptable.
Some pans are made from 20-22 gauge metal. The tone is much better but as the metal is weaker than the 18 gauge, the tone is not held for long periods of time.
The arrangement of notes affects the final tone of the pan. Tuners and pan-makers have discussed for many years which arrangement is best for making standard instruments. The mainstay of this discussion is the Tenor pan. Here the instrument varies in note arrangement and number of notes on the pan.
Some tuners will not tune pans made by other tuners. Because they may not be familiar with the process used to make the pan and the final result may not be to an acceptable standard. One must be aware that the pan making process affects the final tone of the pan and how it is tuned.