Yes "inserts" certainly can be used as direct sends when half jacked. The big difference is that the send point of inserts is after the pre amp & and low cut filter and before the EQ. With Direct sends the send point is Post fader. It utilizes all of the features of the channel. My console allowed the Directs to be either pre or post fader.
Also don't forget if you are going to send from a console to 16 channels of a sound card and want to return those 16 channels back to the mixer you'll need to have at least a 32 channel mixer or do a lot of plugging & unplugging.


John
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