What is Parallel Processing?

If you have already read about FX (Effect) Sends in the section on Channel Strips, you may already understand more about parallel processing than you realize. Indeed, using effect sends and returns is an example of parallel processing. Effect send/return parallel processing involves a copy of the original audio being sent to be processed, whilst another copy of the original audio is left unaffected, and the two signals then being mixed together.

The parallel processing ability of the FX Grid also allows you to have a second copy of the audio signal to be processed at the same time as, in parallel to, the first one. It also allows you to route a copy of the first signal after some effects have been applied and then process that version of the signal in parallel to the first. And if you want to, after applying some effects, then route that second signal back up to go through the same final processing units on the FX Grid as the first one, you can do that too. In short, parallel processing involves copies of the same audio being processed at the same time as each other and heard together. This gives a great deal of creative freedom and control when applying effects and sculpting exactly the right final sound you're after.

Serial vs Parallel

It is helpful, for understanding, to consider the difference between serial effect chains and parallel effect chains. Serial effect chains have the effects applied one after another in series. Parallel effect chains apply effects to more than one copy of the original signal at the same time. Both can be represented on the FX Grid of Audio Evolution Mobile.

1. Serial effect chain.

Imagine you have a recording of a guitar on the track used by this FX Grid. You want to apply both a Chorus effect and a Delay effect to this audio. In this example of serial processing, the audio signal travels through the Chorus effect and then that 'chorused' signal is used for the Delay effect. But, what if you wanted the Delay to be applied to the 'clean' guitar audio, not the already processed 'chorused' signal? Well, you could swap the two effects round on the Grid, but then the Chorus would be applied to the 'delayed' signal which might not be what you're after either. You could duplicate the track and place one effect on either track; that would work but its a bit of a chore to do and it complicates your project. Or, you could place a Send in the first block in the effect chain and have either the Chorus or Delay processed in parallel using that Send/Return. True, that would work, but, in Audio Evolution Mobile, you don't have to do that as you can simply use the parallel processing capabilities already built into the FX Grid. 

2. Parallel effect chain.

So here, using parallel processing, the original 'clean' signal/audio is being sent through the Chorus effect at the same time as a copy of that clean signal is also being sent through the Delay effect. As it is shown here, the two copies remain separate until they are both heard together at the Output. If though, for example, you wanted to apply the same Reverb effect to both the 'chorused' and the 'delayed' signals, you could then simply route the delayed signal back up like this.

As you can hopefully see, this quickly becomes a very powerful, creative and flexible feature to have as it freely allows you to design at which point an effect is applied and to what signal.

NOTE. Since parallel processing involves using copies of the audio signal, be aware that this will increase the volume level accordingly as the copies are combined and heard at the same time. Remember to take this into account and keep an eye on your audio levels.