Re: What would it take to give a LS9-16 the ability to record and have more input/out
Sorry if this veers somewhat from the Yamaha questions, but you might also consider on the recording end of things what actions and what software is required to support recording with both systems. Yamaha pretty much leaves you to figure this out, which is fine if you are comfortable with such things.
The Presonus on the other hand is extremely simple. Just open their included "Capture" program, choose a file location, hit a button to enable record on all channels, and press record. It is really almost stupidly easy. No mixer configuration required AT ALL other than plugging in the firewire cable.
Nothing against the LS9, I have spent plenty of time on them and like them quite well enough, but I do think if recording is a big factor that it's not only more expensive but slightly less convenient than the Presonus. I guess you should ask yourself how important the recording functionality is to you.
From a cost perspective, you could probably own a pair of the Presonus boards for similar cost to a "loaded" LS9-16. Considering they are linkable, that's a lot of flexibility for scenarios like 48ch FOH, separate FOH and MON consoles, etc.