LFO Phase question

Tubiflex

Tubiflex

Inspired
Have I understanded it right, that when you use a modulation effect before the ampblock it must be in mono and therefore the Lfo phase set to 0, to avoid phase problems. Whereas if it is placed after, it can be set to 180 degrees to obtain max stereoeffect ?
 
Not exactly. It adds voices to the effect (1 becomes 2 or however many voices you select in chorus) and you may or may not like the results. It's not quite the same as what happens when you sum L+R from the enhancer.
 
I believe the OP is correct. Setting the phase to zero produces a mono effect, setting it to 180 produces the maximum "pseudo stereo" effect. Since the amp block is mono, I'd set the phase to zero. The number of voices in the Chorus block is a different parameter.
 
Steadystate is correct. The chorus is, always, at least two voices (one for each stereo channel), and offsetting the LFO phase of the right turns a mono chorus into a stereo chorus.
So a stereo chorus into any mono summing block may produce undesirable effects because of phase cancellation.

@ OP: it will be the same, if you place the chorus after the amp but before a cab block in mono mode.
 
What I meant is the chorus block is really just 1 voice in each channel (regardless of how many are chosen) until LFO phase is turned up. Then it gives each voice a different phase offset in one way or another (evenly spaced between 0 and the current setting, maybe). So it becomes stereo and each channel also becomes 2/3/4 voices if the voice # setting is 4, 6 or 8. Turning it up for a 2-voice chorus then summing the channels is the same as what happens in either channel indvidually when increasing LFO phase for a 4-voice chorus.
 
Thanks, your wording is of a physical evidence and clarity without limitation, though I never very well understood it until reading it like this. I never understood very well why in one case a chorus would sound more or less "wide". Now it's all clear. Thanks again.
 
Bakerman said:
What I meant is the chorus block is really just 1 voice in each channel (regardless of how many are chosen) until LFO phase is turned up. Then it gives each voice a different phase offset in one way or another (evenly spaced between 0 and the current setting, maybe). So it becomes stereo and each channel also becomes 2/3/4 voices if the voice # setting is 4, 6 or 8. Turning it up for a 2-voice chorus then summing the channels is the same as what happens in either channel indvidually when increasing LFO phase for a 4-voice chorus.
Click to expand...
A good clarification. Bottom line, no matter how many voices you choose, turning phase to zero will produce a single voice, mono chorus output if its input is mono (what the OP wants), and any non-zero phase value will "stereoize" a mono input as Bakerman described above.

Of course, you could set the phase non-zero before the amp block, you'd just get more than one comb sweep.
 
looks as though you guys have got it all figured out. Funny since I was just looking this aspect (LFO Phase) up a few days ago and came across this comment in the Axe Wiki:

"Cliff: "All the effects, except the drive and amp blocks, are fully stereo. Many of the blocks default to a dual-mono configuration to prevent phasing problems when running into a mono PA." Effects such as Phaser, Chorus and Flanger can be stereo, but are mono by default. This is because a stereo configuration may cause phasing problems when the effect is placed before the (mono) amp sim. Use the parameter LFO Phase (value 90) to switch the effect to stereo.
 
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