Hello again, I'm about to experiment with this concept a bit, and I'm afraid I'm a bit curious about the preamp and LM386 amp deal.
This should be a quote. I found it in the thread as a quote itself, however, I couldn't find the original post and I have no idea about the context.
the link should be http://www.national.com/ds/LM/LM386.pdf
For instance, the LM386 Data Sheet LINK, page 5 top right x200 circuit, suggests a 10uF cap between pins 1 and 8 (you can leave the trim pot in by connecting the cap to the trim and the trim to the other pin for adjustable gain) which helps with oscillation, the "zobel network" is the small cap and resistor from pin 5 (your C1 connection) to ground. This is also there to help with stability and in this high gain application, the circuit needs all the help it can get. As for the "Fetzer" J201 part of the circuit, this is not something I am familiar with myself. You may wish to substitute the output cap (your C1) for something smaller, I use a 100uF to get a kind of mixed mode and enhanced harmonics.
The circuit that is referenced there, including the recommended modifications, does that included just one part of the preamp and LM386 package, or will that work to drive a unit? I must apologize for my lack of understanding of this part of the system.