I remember building a small valve amp, called a Moonlight Amp, some years ago before I moved to Darwin, the original Valve line-up of the amp was as follows:
V1, EF184 (Preamp).
V2, 6SL7 (Phase Splitter).
V3, 6SN7GT (Power Output).
When I built the Moonlight Amp, I substituted a 12AX7 (same amount of gain but in a 9-pin valve type) because I had no 6SL7 valves in my collection of valves, I also had to make my own output transformer as well, since I had no way of buying on, to make the output transformer I pulled apart an existing one and then re-wound the primary and secondary windings according to some calculations I did with the help of a small book I bought from Jaycar Electronics, and to my surprise it worked first time, after that I made a small chassis for the amp out of some thin aluminium sheeting and then designed/etched a PCB for it, after wiring up the amp I connected it up to a power supply that I scored from the Charles Darwin Uni when I did a basic electronics course, the power supply was capable of supplying all the voltages needed to power the amp, after connecting up the amp to the power supply I switched it on and waited for the valves to warm up and then I switched on the HT supply, the amp worked first time and it was pretty loud for what it was, I could get a pretty cool valve overdrive sound from it.
I'm definitely going to have to see if I can find the circuit for the Moonlight Amp, would be cool to try making it again after all these years, I don't have any EF184 valves but I do have an EF86 that I think I could use as a substitute, both the EF184 and EF86 are small-signal Pentodes in a 9-pin valve format, and I know that I can substitute a 12AX7 for the 6SL7, and I think I still have two spare 6SN7GT valves.
Here's a link to a webpage where you can download a pdf of the Moonlight Amp schematic if you're interested in building one:
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