It is a low voltage tube preamplifier, specifically guitar preamp. Uses 12AX7 or ECC83 tube. No complicated circuit. The circuit is similar to the famous old guitar amplifiers bright channel. Low voltage operation, does not require a separate anode and output transformer.
Low voltage tube preamp.
Low voltage tube preamplifier test
His voicedoes notwant towritemuch,rather,here is atest video:
Niceclean andnaturalvoice,withlittledeep voiceandgreatdynamics,but I missthepower.The power supplyto theDC to DC converterhas beenpreviouslydescribed in thecircuit.BUTyou must changebecause they arenoisy, highvolumenoticeable.