The electric bass is a relative newcomer to the world of jazz. The big bands of the 1930s and 1940s Swing era and the small combos of the 1950s Bebop and Hard Bop movements all used the double bass. The electric bass was introduced in some bands in the 1950s and it became prominent during the late 1960s and early 1970s, when rock influences were blended with jazz to create jazz-rock fusion.
Drummers use a drum key for tuning their drums and adjusting some drum hardware. Besides the basic type of drum key (a T-handled wrench) there are various tuning wrenches and tools. Basic drum keys are divided in three types which allows tuning of three types of tuning screws on drums: square (most used), slotted and hexagonal. Ratchet-type wrenches allow high-tension drums to be tuned easily. Spin keys (utilizing a ball joint) allow rapid head changing. Torque-wrench type keys are available, graphically revealing the torque at each lug. Also, tension gauges, or meters, which are set on the head, aid drummers to achieve a consistent tuning. Drummers can tune drums "by ear" or, in the 2010s, use a digital drum tuner, which "measures tympanic pressure" on the drumhead to provide accurate tuning.
Drummers often bring a carpet, mats or rugs to venues to prevent the bass drum and hi-hat stand from "crawling" (moving away) on a slippery surface from the drum head striking the bass drum. The carpet also reduces short reverberation (which is generally but not always an advantage), and helps to prevent damage to the flooring or floor coverings. In shows where multiple drummers will bring their kits onstage over the night, it is common for drummers to mark the location of their stands and pedals with tape, to allow for quicker positioning of a kits in a drummer's accustomed position. Bass drums and hi-hat stands commonly have retractable spikes to help them to grip surfaces such as carpet, or stay stationary (on hard surfaces) with rubber feet.