Regarding the digital Sends (from mixer to computer and network) Pre means before EQ&Dynamics and Post means after EQ&Dynamics, but still before the channel fader. So Pre will send a clean signal from the preamp, or from the network if the channel was set to network input and Digital Send was set to digital.

The digital Returns (from computer or network to mixer) always insert before EQ&Dynamics. Here's the block diagram of the 32R inputs to illustrate the options:

It is possible to 'insert' external processing. The DAW or the VST host needs to see the analog signal input ("Digital Send Source"), the mixer needs to see the USB signal from the DAW/VST host ("Input"). The screenshot shows the settings in UC Surface. The "Digital Send Options" for input channels is by default set to "Pre".

This will NOT work if the channel input is digital (AVB/Network, USB, SD). Then the DAW/VST host needs to see the USB output send of the mixer and returns the processed signal to another channel of the mixer.

This is perfect, thank you. I have it setup so channel 4 (lead) input is AVB, digital send to Studiorack Performer (Post to use the EQ prior to digital out), SR sends to SIII Channel 34, SIII channel 34 is setup for input of USB 34, PRE (no fat channel setting).

Works pretty good, the one thing I seem to be fighting now is I have noise on the digital return (USB 34). you can hear the hiss in the background when there is no singing. If I use the original channel (4), no noise at all. I am trying to figure that out now.

USB 34 by default is routed to Aux In 1 Right, so the left side is missing, which might be the reason for the hiss problem.

AVB 4 -> Channel 4/USB 4 -> SR -> USB 34 -> Channel 34/Aux In 1 R

wahlerstudios wroteUSB 34 by default is routed to Aux In 1 Right, so the left side is missing, which might be the reason for the hiss problem.

AVB 4 -> Channel 4/USB 4 -> SR -> USB 34 -> Channel 34/Aux In 1 R

I am wondering, being a 64S, would this still apply? I know the 64S is considered "free", but maybe there is some background gremlins that still tie to the 32S architecture. Ill test and swing back

The default patching for the 64S in normal mode has all 64 USB/AVB Sends sourced from the mixer's channels and all 64 USB/AVB Returns go to the mixer's channels (before the Analog/AVB/USB/SD selector that is). So for any custom patching you have to sacrifice Sends from or Returns to mixer channels. Probably in Compatibility Mode (34x34 USB channels) the USB patching is the same but only for 34 Sends and 34 Returns.

In Interface mode USB Sends 1-62 are from mixer channels 1-62 and USB Sends 63/64 are from the mixer's Main mix. USB Returns 1-32 and 55-64 go to mixer channels 1-32 and 55-64, USB Returns 33/34 go to Aux Input 1 L/R, USB Returns 35/36 go to Aux Input 2 L/R, USB Returns 37/38 go to Tape Input L/R, and USB Returns 39-54 go to Aux Outputs 1-16.

SwitchBack wroteThe default patching for the 64S in normal mode has all 64 USB/AVB Sends sourced from the mixer's channels and all 64 USB/AVB Returns go to the mixer's channels (before the Analog/AVB/USB/SD selector that is). So for any custom patching you have to sacrifice Sends from or Returns to mixer channels. Probably in Compatibility Mode (34x34 USB channels) the USB patching is the same but only for 34 Sends and 34 Returns.

In Interface mode USB Sends 1-62 are from mixer channels 1-62 and USB Sends 63/64 are from the mixer's Main mix. USB Returns 1-32 and 55-64 go to mixer channels 1-32 and 55-64, USB Returns 33/34 go to Aux Input 1 L/R, USB Returns 35/36 go to Aux Input 2 L/R, USB Returns 37/38 go to Tape Input L/R, and USB Returns 39-54 go to Aux Outputs 1-16.

I have not changed the mode from default, which I am assuming is interface (not DAW). So what I have setup right now (I am testing tomorrow), Channel 4 (mic) as an example, to Studiorack Performer input, output on Studio rack performer goes to channel 55 on board (USB channel 54 input).

And just to check, USB send on channel 4 is pre (so technically, no FAT channel processing whatsoever). I could change this to POST for the EQ/COMPRESSION PRIOR to studio rack, and then on channel 55, shutoff all the Fat channel processing. Make sense?