How often to replace heads depends on many things - not the least of which is how much are they used.
Since resonant heads (bottom heads) don't get hit, they do have a longer life (but they will stretch out and do need to be changed.
If the drums are in a stable evironment (not in and out of the cold, etc) the resonant head can last for a while. As a rule, I change mine once a year (or slightly more often if I am having tone problems). However, I;ve sent resonant heads that lasted for a few years and still were functional.
Regarding the kick drum. Engineers, often prefer no head - to allow for freedon of mic'ing, and more control. However, many drummers prefer the front head in place for the tone they want. Often the hole is a compromise for mic'ing purposes.
As a drummer who also enginners sessions - I find for recording,taking the front head off provides the widest range of options for mic placement - thus for recorded sound.
Since resonant heads (bottom heads) don't get hit, they do have a longer life (but they will stretch out and do need to be changed.
If the drums are in a stable evironment (not in and out of the cold, etc) the resonant head can last for a while. As a rule, I change mine once a year (or slightly more often if I am having tone problems). However, I;ve sent resonant heads that lasted for a few years and still were functional.
Regarding the kick drum. Engineers, often prefer no head - to allow for freedon of mic'ing, and more control. However, many drummers prefer the front head in place for the tone they want. Often the hole is a compromise for mic'ing purposes.
As a drummer who also enginners sessions - I find for recording,taking the front head off provides the widest range of options for mic placement - thus for recorded sound.