On my old DP-01fx I could turn on the internal reverb and add it to an input for playback or mixing down the master. I'm a bit confused about how I can go about this on the DP-24SD. Can this be done with the internal reverb effect or do I need an external effects unit to accomplish via the external send? Excuse my lack of understanding on this. If someone could explain it simply, I would be greatful! Thanks in advance!