Fastest Motor - Stepper vs DC

Hi all.I am building a drum machine for a university project and i need some help.

I am currently controlling a 9v stepper motor with 4 wires(Bipolar) with pic 16f877a, programming with micro c.

The speed i have reached it's not very fast between the bits (Forward and Backward movement and again)                                     so it's a little slow playing with the stick.

I want to make this movement faster.Which motor is best for this Forward and Backward movement? A stepper motor or a DC and how many volts?What do you recommend?

Also i didn't found  L293D and i am using L293B (Full bridge) and it's working fine.You think i can do my job with B or you suggest    the L293D ? I think a difference it's a diode but i don't know what it does.

Thanks,any help appreciated. 

9v battery?

What is your main power source? are you using a 9 volt battery?

9v battery?

What is your main power source? are you using a 9 volt battery?

9v battery?

What is your main power source? are you using a 9 volt battery?

9v battery?

What is your main power source? are you using a 9 volt battery?

9v battery?

What is your main power source? are you using a 9 volt battery?

9v battery?

What is your main power source? are you using a 9 volt battery?

I use a 9 volt battery or a

I use a 9 volt battery or a AC adaptor with 9 volt (or more - less,switcher) dc output.