Don't have a 990.

Have not read the manual.

Can anyone tell why one would even invite "double bass" or why anyone would ever design for it?

At most I can see having a single big honking button on the front panel or remote that says "push here for double bass" - and have it defeated in all other situations. By the sounds of the gyrations explained above, Outlaw is making this way too hard.

Didn't they learn from the 950?

Jeff mackwood