WICKED WIKI 12: Parallel Paths

yek

Contact Fractal for your Custom Title
In the good old days of amp combos and heads, parallel effect loops would let you add effects to the sound with no impact on the amp tone itself. As opposed to series effect loops, where the entire signal is processed by the effects device and therefore subject to the quality of that device. Preserving tone integrity was the holy grail.

With the Axe-Fx there's no need anymore to use parallel paths to preserve tone integrity. There's no tonal difference between a signal going through a delay in series and a direct signal combined with a separate signal going through a delay in a parallel path. It's all digital, remember?

Still, there are useful applications for creating parallel paths. Such as:
  • Ability to add an effect to work on effect trails only. For example, adding a tremolo to delay trails to emulate a TC Electronic 2290, or adding a Phaser to those trails (see factory preset Fazed Delay), or gating a Reverb, etc.
  • Ability to adjust the amount of effect level without affecting the direct signal. With effects in series, adjusting the Mix parameter will not just change the effects level, but it impacts the level of the direct signal as well. Note: with the release of firmware 11, the Mix value does not affect the dry signal (up to 50%).
  • Ability to put more effect blocks in a preset than when having everything in series in one row.
  • Ability to make sure that there's no reverb applied to delay trails.
  • Ability to use two amps in a preset, with one set to use power amp modeling, and the other without.
How to create a parallel path?
Split the signal to a separate row (1 or more) above or below the main one, add blocks or shunts to the rows, and merge the paths again. Merging is not necessary, but two long rows connected to the output on the grid may use more CPU cycles than a merged row (shunts use CPU).

A couple of important notes.

  • It's not useful to put 100% "wet" effects in parallel paths. Think of Tremolo and Compressor. These kind of effects need to operate on the entire signal, except when they are used to work on a preceding effect.
  • Splitting a row doesn't affect signal level. But summing parallel rows (on the grid or in the output mixer) does. Just like two cabinets, fed by one amplifier, will sound louder than one. More information about dBs (source: GM Arts).
  • You can work around doubling signal level. In effect blocks in the parallel path, set Mix at 100% and use Level to dial in the desired amount of effect. Or set Mix at 100%, Level at 0 dB and use Input Gain to dial in the amount of effect. If Level is very high, overall volume may still increase.
  • When bypassing effects in the parallel row, the overall signal level may change (because of summing multiple signals. You can work around that. In effect blocks in the parallel path, set Bypass Mode to Mute In or Mute Out. Do not use Thru or Mix 0%, in order to avoid doubling the signal level.
Wiki: Series/Parallel

To get a list of all Wicked Wiki threads: type "Wicked Wiki" in the Search box.
 
Last edited:
Great info here, Alex!

I use parallel effects all the time, mostly so I don't have signal level issues when switching delay on/off.
 
EXCELLENT. I am shooting a video on parallel/series right now and I'll incorporate this too (and give credit where credit is due!)

Well done sir.
 
Awesome Scott! Thanks as well Yek! I honestly don't understand parallel vs. series too much and haven't messed with incorporating parallel into my presets. As Scott mentioned in one of his videos, most guitarists including myself come from a more 'series' background, as that's how most pedalboards are constructed.

Scott, while you're here, I have a basic question after re-watching your reverb video. At the end of your chain, you put the verb in parallel and have another shunt going to the output that preserves your original guitar tone. What's the point of this? This might be a stupid interpretation, but if you don't have copy L to R set up, in axe FX, does each square of the axe editor go to a different output? AKA the top goes to out 1 L, top mid to out 1 R, bottom middle out 2 L, and bottom out R? If so, that'd mean that your left speaker was getting the reverberated signal, and the right would be getting the signal with no reverb?

Just trying to understand why you'd want your dry signal at the end of the chain. Parallel makes a bit more sense to me at this point in the middle of the chain, but I'm sure your video will help fill in some gaps. Thanks yek and scott!
 
Awesome Scott! Thanks as well Yek! I honestly don't understand parallel vs. series too much and haven't messed with incorporating parallel into my presets. As Scott mentioned in one of his videos, most guitarists including myself come from a more 'series' background, as that's how most pedalboards are constructed.

Scott, while you're here, I have a basic question after re-watching your reverb video. At the end of your chain, you put the verb in parallel and have another shunt going to the output that preserves your original guitar tone. What's the point of this? This might be a stupid interpretation, but if you don't have copy L to R set up, in axe FX, does each square of the axe editor go to a different output? AKA the top goes to out 1 L, top mid to out 1 R, bottom middle out 2 L, and bottom out R? If so, that'd mean that your left speaker was getting the reverberated signal, and the right would be getting the signal with no reverb?

Just trying to understand why you'd want your dry signal at the end of the chain. Parallel makes a bit more sense to me at this point in the middle of the chain, but I'm sure your video will help fill in some gaps. Thanks yek and scott!

PM or post (I might not see just the post) if my video doesn't make it clearer for you.

In essence, you can do whatever you want for whatever reasons you want to. I do what I do because: a) it works for me; b) I can; and c) I'm digging what is happening.

I'm not a rocket surgeon or a brain scientist... ;)
 
Excellent stuff! I've been doing some parallel routing but couldn't get the effects to sound "right". Never realized until now that the mix has to be up to 100% and then use Level. Thanks Scott. One of the great things about this board is you can always learn new things about "the box"!
 
... To get a list of all Wicked Wiki threads: type "Wicked Wiki" in the Search box.

Ahhh! Thanks for this search term! I realize the topic will be in the Wiki ... but here is the link to the discussions! :encouragement:
 
Back
Top Bottom