This means there are three booleans in the options related to sound now. The first one enables/disables sound entirely and is default on. The second is only relevant if the sound is enabled and says "use a mockingboard if present". Again this is true by default. Finally, the this says "use a speech chip on the mockingboard if present" and is only relevant if the mockingboard is also enabled.
So, the basic approach now is to default the "best" sound options and auto-detect the sound HW at launch. The user can then use the options to downgrade their sound all the way to basic Apple // sound or turn off the sound entirely.