This doesn't answer your question but it's hard to visualize these things without an Oscilloscope, surf e-bay, you can get a used dual trace for under $100 that is well good enough for audio work.
With an O'scope you can see exactly what/where/when you get distortion (and many other things) by applying a sine wave to the circuit input and monitoring it with one trace, then using the other to probe to move along through the circuit comparing the two traces you can see where the signal changes and how it changes.
Once you get into using an O'scope, you'll hardly ever use anything else in debugging. I avoided buying an O'scope for years, but then after I did, I kicked myself for not buying one years ago, once you get one you can trace things through your circuit and learn/fix things that were beyond your grasp before.