Yamaha DTXpress/DTXplorer/DTXtreme

Hi guys,

I have 2 questions I was hoping you caould help with:

1. How do I layer my pads/ cymbals for bigger sounds? I have read about 
it in a tips section of DTXpressions but don't know how to do it.

2. I am playing with a guitarist - whats the best way for both of us to 
hear each other through headphones - don;t want to blast the neighbours 
out of it! - (one input double output jack adapter perhaps?)

Suggestions and help appreciated.

Thanks,