PreSonus Blog

Parallel processing splits a signal into two or more parallel channels. Bi-amping is a common example of parallel processing:

• One channel processes low frequencies.
• The other channel processes high frequencies.

The two channels then mix together to a common output (e.g., the Main output bus). You generally don’t want the original audio that was split to appear in the mixed output of the two channels.

Parallel processing has many applications, like altering stereo image, emphasizing transients, doing creative compression effects, super-wide reverbs, and more. Studio One Professional has a Splitter module that makes parallel processing easy within an FX Chain. However, this isn’t always a perfect solution, for reasons described later. And Studio One Artist doesn’t have a Splitter—so let’s look at an alternate way to do splits.

Splitting with Buses

The traditional way to create a split for parallel processing uses buses. You insert pre-fader sends in the channel with the track you want to process. These go to two FX or Bus Channels (fig. 1). With pre-fader sends, the original channel’s fader can turn down all the way. This prevents the signal from going to the Main bus, yet audio still proceeds to the parallel paths.

Figure 1: This example of traditional bus-based splitting provides bi-amping.

However, Track Presets can’t save a combination of tracks and buses, only tracks. So, let’s speed up your sessions with a Track Preset-friendly solution.

Splitting with Tracks

This option accomplishes the same goal, but you can save the setup as a Track Preset for instant recall. First, we need to do a little prep work. The parallel channels receive their inputs from Track 1’s output (note that the parallel tracks’ input fields in fig. 3 show “Track 1”). So, we can’t turn the Track 1 fader down to have the equivalent of a bus’s pre-fader send. Although there are some instances where you may want the original sound mixed in with parallel processing, most of the time you want to hear only the outputs from the parallel-processed tracks.

Fortunately, there’s an easy way to do a pseudo pre-fader send. In Song Setup, create a Dummy Output and don’t assign it to anything (fig. 2). We don’t want it to go anywhere. This lets the parallel processed tracks still receive their inputs from Track 1, but Track 1’s output feeds the Dummy bus instead of the Main bus. So, you won’t hear Track 1’s original audio.

Figure 2:  Use Song Setup to create a Dummy bus to nowhere.

Fig. 3 shows the track-based splitting configuration. Aside from assigning the source track to the Dummy bus instead of the Main bus, here are the differences compared to fig. 1:

• The parallel channels need to have their Monitor buttons enabled.
• If you want to blend in the original sound, assign its output to the Main bus instead of the Dummy bus. Because Track 1’s fader serves as a master input level control for the audio feeding the parallel paths, you have the equivalent of a post-fader send if needed.
• Solo Safe isn’t enabled automatically. To enable it, Shift+Click on the Solo buttons in the parallel channels.
• And (drum roll, please!) here’s the big advantage: You can select all three tracks, and save the configuration as a Track Preset. Just remember that any project in which you use this track-based configuration needs to have a Dummy output available in Song Setup.

Figure 3: You can save this parallel processing configuration as a Track Preset.

Disadvantages Compared to Studio One Professional’s Splitter Module

• Unlike an FX Chain, this parallel processing method doesn’t insert neatly in a track, and requires an additional channel for each split you want to add. (The FX Chain’s Splitter can have five splits within a single channel and can do frequency-based splits, which is ultra-cool.) A mitigating factor is that once you set the level for the audio track that splits into the parallel tracks, you can hide it.
• Another limitation is there’s no panel for Macro Controls. For complex FX Chains with multiple splits and processors, Macro Controls can save a lot of time when you need to tweak the sound.

Advantages Compared to Studio One Professional’s Splitter Module

• With channel-based parallel processing, the effects providing the processing are exposed. You don’t have to open up the FX Chain to edit, delete, or replace them.
• Because the effects are in channels, you can expand the micro-view. This lets you modify parameters and see characteristics (like EQ curves) at a glance.
• It’s not possible to have inter-effect sends within an FX Chain. With the track-based approach, the splits can have sends that go to effects in other splits. For example, a sound in one split could trigger a dynamic EQ’s sidechain in a different split.

The bottom line is for Studio One Artist, track-based splits are a great way to create parallel effects. And with Studio One Professional, FX Chains provide exceptional functionality—but even so, track-based splits can perform some tricks that FX Chains can’t do.