Sprinkler valve

The next step up from a ball valve, this is essentially a commercially produced diaphragm valve. However, they are unfortunately designed to open relatively slowly to prevent "water hammer", and the large number of internal turns decreases the flow of the valve (to roughly 60-70% of a piston/diaphragm valve with the same diameter).

The performance can be improved by replacing the stock solenoid-valve vent with a pilot valve with more flow. Most often this is a blow gun, although for larger valves a ball valve or even a smaller sprinkler valve can be used. This operation is often called modding the valve.
You can download a video of how to modify a sprinkler valve here

The GGDT's website has valve data for sprinklers in it's design library

stock sprinkler valves can be fired remotely using very simple electronics, check out the remotely activated valve tutorial

Troubleshooting

If you are having problems with your sprinkler valve, these are some things to try

Valve "Honks" or "sounds like an airhorn"

You need a larger pilot valve. For more information, see honking.

Valve won't seal

If your valve leaks air out the barrel there is a good chance that there is dirt, PVC shavings etc. in the valve preventing it from closing properly. An easy way to clean the valve it to just hook it up to a hose and flush water through it while cycling the valve a few times. If that doesn't fix the problem then you should disassemble the valve and clean the diaphragm and seat. Check for any plastic chips that may have entered the valve. Smear the diaphragm and seat with lithium grease to promote a seal.

For other problems, visit the Sprinkler Valve Troubleshooting Guide [1]