Blackmagic Forum

Hi. I'm wondering if there's a way to patch a bus into a specific input on the master bus.

For example, instead of using the LFE send on the panner window, I want to send part of a track to a mono bus that I can run some plugins on (like Waves LoAir) and then pipe that into the LFE on the master bus. There doesn't seem to be any way of doing this. I thought I could use the "Patch Input/Output" window but the only way I can make this work is to patch the bus directly into the LFE channel on my hardware output (bypassing the 5.1 master bus). Trying to patch a "bus direct" output to a "bus return" on a different track using the "Patch Inputs/Outputs" window does nothing.

It looks like I could get something similar by piping the LFE bus back into a new audio track and then sending THAT track to the LFE but it seems like a goofy workaround that will chew up an unnecessary track.

jdent02 wrote:I want to send part of a track to a mono bus...

"part of track" do you mean LFE channel from 5.1 track? You can try to use LFE Filter from Fairlight FX library to separate LFE channel from surround track.

Not exactly. I meant sending a track to a mono bus, running LoAir on that bus to create LFE effects (so none of the direct sound from the track would pass through the plugin, only the generated bass content), possibly compressing the result, and then sending that bus directly to the LFE channel of the main output.

The Fairlight LFE Filter can only lowpass an existing LFE channel in the track it's placed on. It can't send it anywhere or do anything else with it.

One option that may work for you is to modify the clip attributes - audio for the source clip so it has 2x 5.1 tracks - 1 with mute LFE, the other with only LFE. You can then apply plugin to that track (or seperate 5.1 bus if you need to) and have them all be bussed to final 5.1 bus for output.

jdent02 wrote:Not exactly. I meant sending a track to a mono bus, running LoAir on that bus to create LFE effects (so none of the direct sound from the track would pass through the plugin, only the generated bass content), possibly compressing the result, and then sending that bus directly to the LFE channel of the main output.

You mean this in picture 1?

A1 - source audio 5.1
A2 - L, R, C, -, Ls, Rs channels routed from A1
A3 - LFE channel routed from A1 (You can use a mono track, not like 5.1 in the picture.)
M1 - common audio from A2 (L, R, C, -, Ls, Rs) + A3 (LFE)

The Input / Output patch is shown in Figure 2.

jdent02 wrote: It looks like I could get something similar by piping the LFE bus back into a new audio track and then sending THAT track to the LFE but it seems like a goofy workaround that will chew up an unnecessary track.

Exactly. Route the Buss through a Timeline Track in Thru (enabled in Path Settings) with Boom Only enabled (Option + click the Pre button in the Panner). Tracks are cheap especially with Fairlight's efficient processing core.