Chromatic pitch pipes are favored by "a cappella" singers and timpanists. Occasionally, timpanists use the pedals to retune while playing. After them came a long line of noblemen, privy councils and more timpanists. Jonathan Haas is one of the few timpanists who markets himself as a soloist. Gone were the old ways of timpanists only playing the tonic and dominant. Modern timpanists execute such passages with felt sticks. Thus, most timpanists own a great number of sticks. However, many professional timpanists prefer skin heads because they produce a "warmer" timbre. Even when gauges are available, good timpanists will check their intonation by ear before playing.