SoundCrumbs - The amp in this picture is a GU-50 based... | Facebook
Buy 2pcs GU-50 ГУ-50soviet Power Pentodes/m.quad/soviet Radio Tubes/vintage Vacuum Tubes/retro TV Radio Tubes/electronic Tubes/new Online in India - Etsy
New GU50 push pull taking shape. : r/diytubes
Shots of a GU-50 tube amp I recently designed and built. - YouTube