I'm really not sure how to respond to that. I have had no problems with delays, but they are there.
Here is my specific data for a sampling of adjustments:
Denon AVR-X4400H
1) Increase/decrease sub level - happens in real time, no delay, no pop (I turned it up in extreme to make sure it was actuating as there is no click or any indication other than the change in the sub level). This is ideal as it allows you to adjust to your preference without interruption.
2) Use of Graphic EQ - same as above - happens seamlessly as you do it (just like turning a bass or treble knob on a vintage unit).
3) Changing the crossover frequency - the sound drops out for about 2.6 seconds.
4) Switching bass from "LFE+Main" to "LFE" is exactly the same as above - about 2.6 second delay.
Hoping
@PENG can enlighten us on this, but I am inclined to believe that any change in the digital domain will probably take the ~2.6 seconds, and any analog change will happen in real time.
For me, once you have the interruption from the music dropping out, the difference between, say, 2 and 3 seconds is inconsequential. I guess 5 seconds might start to seem too slow, but these are not changes I make very often at all.
I can imagine that the lower level Denons might perform the same task using a slower processor, resulting in a slower response time; however, I would not expect the 3300 to be much slower if at all - Denon may spec a different processor for their least expensive units, but it surely makes no sense to buy and inventory 12 different levels of processors for 12 different AVR's (or however many Denon sells).
If I am right on this, that may be another reason that Marantz and Denon stick with the Graphic EQ - you can listen as you adjust it in real time!
Perhaps someone with a PEQ Yamaha can test this!
Personally it seems PEQ without REW is essentially too many adjustments to control without a good source of information (as REW would provide) as to how to adjust it.
To get specific (as I understand it - and I know I can count on being corrected if I am mistaken
) for the PEQ you have to pick the exact frequency that you want an adjustment centered on, then you select how wide of a bandwidth (q) you want the adjustment to effect, then you select the amount of increase/decrease.
Since we don't hear or think of pitch in terms of hertz, deciding the frequency for adjustment is pretty much a trial and error proposition unless you have a FR measurement to use as your guide and can verify with another FR after the adjustment.
OTOH, I'm sure that the Yamahas that have PEQ probably have a default set of frequencies and default bandwidth (or q) such that you adjust it like a GEQ until you decide to get into the more advanced settings!