You've never played an amp that sags?
That has nothing to do with speakers, sound dispersion, etc.
This gets to what I see as the core of the issue.
Using an amp without pedals for rock and roll, especially a single channel amp, is educational because we have to learn how the amp reacts to the guitar input, which is based on our picking and where the volume knob is set. We pick lighter or roll down the volume and the amp cleans up, hit the strings hard or roll up the volume and it breaks up. Some players set their amps to reach a good crunch and then push it to full distortion with a pedal;
David Grissom talks about this a lot in his videos. Doing it either way puts us in the same position of learning the “feel” of the interaction with the guitar and amp. It’s rock and roll so we tend to enjoy running on the edge of uncontrolled acoustic feedback which is where the system is very responsive to every little thing.
Some people who use an amp with pedals run the amp right on the edge of breakup always and use a distortion, or boost, pedal to push the amp that little extra bit. The sound is very close to the previous situation but they rely on a pedal to make the amp crunch or go beyond that point, and that isolates them from the feel of the guitar and amp because the pedal is doing some of the work. It’s close but few drive pedals have the nuances of the amp itself so the feel suffers somewhat.
There’s been a trend for a while that says to use pedals to sculpt the sound and feed them into a clean amp, using the amp only as a way to get the volume they want. Because the pedals lack the feel of an amp, and the amp isn’t working hard enough to make the tubes and transformer saturate, and the power supply grunt, the overall feel is seriously affected. Even if the amp is running loud enough to cause the acoustic coupling to form with the guitar, it still lacks the amp’s circuitry being pushed past its limits. It’s a more controlled sound but it also lacks the dynamic behavior of an amp being pushed beyond its limits. The end result is a feeling of being isolated from the amp.
I suspect that those who don’t innately know what “feel” is are using their gear in the later way. It’s not right or wrong, it is what it is. The solution is to step away from the drive and boost pedals and rely on the amp for those things, but a clean amp has to be so loud to get the power amp and power supply straining that it discourages experimenting.
As Cliff said, people tend to run their modelers at too low of a volume. That seriously affects the feel. I treat my modelers as single channel amps for the most part because I want the interaction and feel. It’s loud, often peaking just about 100 dB and I’m standing about 4 feet away. It’s the same as I get with my tube amplifiers.
That’s what I see from here.
