Device that makes your signal nicer and louder and even distorts it if you want it to

From the vendor

I don‘t think I have to tell you all to much about this. Use this PCB to build yourself a clone of the rightfully beloved Benson Preamp. -Makes your signal nicer -Makes your signal louder -Distorts your signal if you want it to Thats all you need

Build Docs

You can also get this as a kit from Musiking here