Too often I’ve watched people buy timpani heads assuming you buy it based on the size of the drum shell/bowl (32, 29, 26, 23, or 20”). Timpani heads are different, as they are larger to allow for the heads to stretch over the edge of the bowl.
Timpani heads are categorized in two types; standard and extended. Standard heads measure 1” larger than the bowl, while extended heads are 2” larger. Most modern timpani will use extended sizes.
The most popular brands of drums used by schools, community bands and orchestras are Adams, Ludwig, and Yamaha. Rest assured, all Adams and Yamaha drums use extended heads, so your actual head sizes will be 34, 31, 28, 25, and 22”. Modern Ludwig drums are also extended, however, their older drums are a bit more troublesome, as their drums manufactured before 1978 had more sizes (including 25, 28, and 30”) and used standard sized heads.
The best method for sizing is always to remove and measure the diameter of the old head. If you are still having difficulty, ask your local music retailer or speak to a percussionist knowledgeable of this info. The last thing you want to do is order a head you do not need and cannot return.
Be sure to measure straight across the bowl’s center.
(31” head)
(New heads now have markings as to their actual size, making for easier replacement.
(Evans 31” head)
Ludwig labels their heads as extended or standard, with the bowl size as the head size. Their heads have the actual model printed on the top of the head itself for easy matching. See their head sizing chart here:
Evans and Remo have sizing charts for practically every set of timpani out there.
Grand River Percussion Solutions “the Stream” 