I would find clips on Utube and other places, read forums etc to find an amp I like the sound of, and then go from there.
I made a PCB for the Marshall 12watt amp because its popular and sought after, I posted the gerber files somewhere on this site for the PCB files.
If you are just after the pre-amp then you could easily build it on a Solder-less Plug-in Breadboard to try it out, change the tone stack and gain components etc.
How complicated do you want to go ? A simple pre-amp or multi channel pre-amp ?
What sort of power are you going to run it at and is it for home or are you going to use it in a band etc ?
I made a PCB for the Marshall 12watt amp because its popular and sought after, I posted the gerber files somewhere on this site for the PCB files.
If you are just after the pre-amp then you could easily build it on a Solder-less Plug-in Breadboard to try it out, change the tone stack and gain components etc.
How complicated do you want to go ? A simple pre-amp or multi channel pre-amp ?
What sort of power are you going to run it at and is it for home or are you going to use it in a band etc ?