Evans EQ4 '56 Calftone Drum Heads look, sound, and feel like natural calfskin, but they've got the modern benefits of manufacturing consistency, fit, and tuning range thanks to the 360 Technology design. And they won't become floppy under humid conditions!
This 18" bass drum head is made from a single ply of 12-mil Mylar blended with "secret ingredients" to produce the rich, vintage tone of calfskin.
The EQ4 fixed internal overtone control ring takes out annoying high overtones, so you don't have to use a pillow or other dampening devices to cut ringing.
Jazz, funk, rockabilly, classic country, and any other genre that prizes richness of sound over volume and punch will benefit from Calftone, but if durability under heavy playing is a key factor you may want to look for a different model.
The look of this head screams "vintage", and can work easily well on the batter side or the resonant side of your bass drum.