Well, I don't care what I'm sounding like. I'm just telling the truth. Just consider this:
Your theory will have to change when one puts multiple analog pedals in a loop. Just enough to make the cancellations be heard.
What I say - which is actually what every amp manufacturer (Peter Diezel is just an example) will tell you (those **** guys are always trying to be smarter than everyone else! - btw: I don't count ad hominem arguments as real arguments) - will stay the same, no matter if you put a analog, a digital or whatever in the loop. I prefer to tell people how it is.
If one likes the sound of an analog pedal which can not be set to 100% wet in a parallel loop or not, well, I could care less.
I want to give anyone who asks the information to at least be able to figure out what goes wrong when things go wrong. And that is not a question of digital vs. analog in a parallel loop.
I think I have been a little unclear with all the talk about 100% wet.
I'm quoting you:
"Since the Mesa parallel loop maximizes at 90% wet regardless of the effect used, there is always at least a 10% unaffected signal being produced. Since this signal follows a shorter pathway (in terms of length and total resistance of the circuit), it will produce perceptible sound before an affected signal does. The question isn't if it will happen that way, since the loop's circuit design guarantees that it will, but a matter of how much discrepancy is produced. "
I totally agree.
But I do not mean setting the loop to 100% wet. I mean setting the fx to 100% wet, so that no unaffected signal passes through. Then you will not get any phasing issues at all, because the unaffected signal travels inside the amplifier and ONLY the affected signal is added. Voilá, no phasing issues! Be the fx analog or digital.
I'm gonna post what Peter Diezel says, because the quoted portion of your reply shows I didn't get my point across:
"There are 2 ways to handle effects signals. If you use the serial return, then the signal path of your VH4 is interrupted, the signal is sent to the processor, gets more or less processed, then sent back to the serial return into the power amp. Digital effects units often digitize this signal, then process it, then convert it back to analog, then send it to the amp. This is called ADA conversion. It is necessary for digital effects units to do this to your guitar signal, so that it becomes a digital code which the processor can read and understand. Your tubes, however, need a old fashioned analog signal, so the processor needs to convert the signal back to analog before it goes back to the amp. Generally, even in highest quality effects processors, this causes a change in the original signal, typically a loss of tonality and warmth, also noticeable as a “harder” sound. When you use the serial loop for an effects unit like this, then your signal will have been ADA converted at least once. Tone junkies and vintage freaks alike will more than likely have hives developing by now. But - as always, there is a better way. Use the Parallel loop and the mix control in the front determines how much effect signal is being added to the original signal, which now still flows through the amplifier. There is always an analog connection between the send and return jacks; a parallel loop!
Important: You must set the mix control on the effects unit to 100% wet when using the parallel loop. Otherwise there will be nasty phasing problems resulting in unsatisfactory tone. The signal portion that is unaffected by the mix control in the effects unit would reach the amplifier at a different time due to the cabling, and cause phasing cancellations."
(
http://www.diezel.ch/en/products/pdf/vh4_manual_english.pdf)