A Guitar Pre-amplifier using the $2 6J6 valves from oatleyelectronics.com this gives your guitar amp a real valve sound.

I built this pre-amp after buying oatley valve amplifier kit, i found oatleys preamp has a noticeable 50Hz hum. This project has no 50Hz hum, and can be distorted by overdriving the valves (by increasing valve 1 & valve 2 volumes, and decreasing the master volume) to giving a real valve overdrive.