A variation on the classic Rangemaster Treble Booster from D*A*M.  The Red Rooster germanium booster uses a NPN transistor so it can run off a normal power supply, and features a capacitor blend on the input to sweep between treble boost and full range boost.

This has a lot of boost on tap - it will crush anything it's put in front of.  It's also happens to sound great, so I'd recommend building it if you have the parts spare and valves to punish.

There's an excellent article here from R.G. Keen as to how a Rangemaster works, including bias voltages and transistor selection.  Electrosmash  also has a very detail explanation.

D*A*M RED ROOSTER BOOSTER - POINT TO POINT LAYOUT

NOTE:  Stock trimmer setting is 3k9 for a Rangemaster. 

D*A*M RED ROOSTER BOOSTER - ON THE BENCH

Not exactly parts as per schematic.  I used a 2n7 instead of a 4n7 cap and a 30k trimmer instead of a 5k trimmer as I had a spare sitting right in front of me at the time that I thought I might use instead.

I used an old AC176 NPN germanium transistor with axial and tropical fish caps for added mojo.  It sounds killer, which apart from the additional gain, I think is the AC176 working its magic.    

D*A*M RED ROOSTER ON THE SCOPE

Signal source:  440hz sine wave, approx 130mv TRMS

Range 0%, with a fair bit of boost (can't remember where it was exactly).  There's still more boost available, I stopped here before it started to clip the sound card input on my laptop.

Range 50%, with boost pulled back

Range 100%, still quite a bit of boost left, as mentioned above, I stopped so as to not clip the sound card.  It's getting pretty dirty by this stage, producing a lot of harmonics.