Electronic Parts &
- Parts Express - The #1 source for audio, video & speaker building components.
- Madisound Speaker Components - Global distributor of audiophile speaker drivers and loudspeaker parts since 1972. Located in Madison, WI.
- PHY-HP - French company selling speaker drive units, cables and connecters.
- Richardson Electronics – Local supplier of electron tubes and vacuum devices.
- World Tube Audio Portal - An excellent list of links to online tube audio resources and manufacturers.