What is meant when a guitar amplifier does or does not "take" guitar pedals?

Question

I've been researching guitar amps to buy for a first-time electric guitar learner (me). Among the many types available, I've encountered a few described as "modeling" amplifiers, which appear to use digital circuits to recreate the tone and effects of other amplifiers or musicians.

I understand that using a particular pedal in conjunction with an amp that is also applying a bunch of effects could be counter-productive or result in a mess. In a few reviews, more experienced guitar players have said something along the lines of the amplifier not "taking" pedals.

Is this just a recommendation to not use pedals with the amp when applying its internal effects? I can't think of a reason why a pedal (such as an overdrive or delay) wouldn't be compatible with a modeling amp running in otherwise clean-signal mode.

Answer 1

First, an amp "taking pedals well" has little to do with modeling amps specifically or internal effects of any kind. I don't have much experience with modern modeling amps but I'd guess that they are subject to the same things as real amps. Though, in general, when people use that phrase it's usually a matter of the gain staging when using pedals like overdrives and distortions.

But it's one of those things that can mean different things to different people and whether it does it "well" is of course subjective. I'd say people are usually talking about one of two things though:

1. The amp is clean and has enough headroom that you can crank gain-based pedals like overdrives and distortions and get the sound from the pedal and not from the amp. So if you use a particular overdrive pedal you'll get the sound of that pedal but a completely different sound when you use a different one. The inverse—amps that don't take pedals well in this way—would be amps that always have a distinct sound even when you're getting most of the gain from a pedal.
2. The amp is of the variety that you'd crank to get the sound of the overdriven amp itself. But when you add a gain pedal on top of that it sounds even sweeter or still sounds good in some way. Amps that don't take pedals well in this way might crap out on you when adding a pedal on top of amp gain or it doesn't really change the sound much or sounds too muddy or flabby or something.

Answer 2

It may have to do with the amp having/not having an effects loop. More info can be found here: https://www.dawsons.co.uk/blog/how-to-use-an-effects-loop-on-your-amp

"An effects loop is an input/output that allows you to place effects between the pre-amp section of the guitar – where it gets its tone and the power section of the amplifier – where it amplifies the sound. This means that your pre-amp can be put anywhere in the signal chain rather than having to be the last stop. "

Answer 3

I think its simpler than that. Some amps just sound harsh, or get extra muddy with pedals. They lose their clarity, and tonal quality. Your guitar may get buried in a mix and not cut through well if your jamming with a band. It just sounds bad. there may be one decent combination of settings between the amp and pedals that actually sounds decent.

While others amps have amazing clarity, bringing out all the subtle nuances of a pedal's different parameters incredibly well. They offer a wide range of tonal possibilities that all sound good. The pedals do their job well without too much extra noise or hissing. They don't degrade the amps original tone.

A 10 watt solid state 80s peavy practice amp are harsh and bad. Those don't take pedals (or guitars in general) well.