| Amber | Tube Amplifiers, Cables, Speakers |
| Balladaudio | Tube Amplifiers, Tube CD Player |
| be.audiophil | Private Tube Audio Sites |
| Dinleti Music | Retailer |
| HiFi-Analyse | Tube Amplifiers, Retailer |
| Infotronix | Manuals, Schematics |
| NOS Electron Valves | Tubes |
| PhaSt Audio | Tube Amplifiers |
| Rör & vinyl | Private Tube Audio Sites |
| Servicesound | Tube Amplifier Service |
| Skip Simmons Amplifier Repair | Tube Amplifier Service |
| Triode Systems | Kit Building Service |
| Tube Town | Tubes, Parts, Kits |
| tubeamp | Private Tube Audio Sites |
| World Tube Audio Kits | Serious Tube Amplifier Kits, Tube Amplifier Service, Speakers |
| Xindak Electronic | Tube Amplifiers, Tube SACD Players |
| Yarland | Tube Amplifiers |