| Decware High Fidelity Engineering - amplifiers, loudspeakers and more |
| The HornShoppe - single driver horn loaded loudspeakers |
| Digital Systems & Solutions - CD enhancements that really work |
| Hawthorne Audio - open baffle loudspeakers, the Spud amplifier |
| GreenValve Audio - Type 10 SET amplifier and more |
Wild Burro Audio Labs - the Betsy open baffle driver
|
La Dolce Audio - Toe tapping pentode vacuum tube amplifiers
|
The FleaWatt Blog Spot - Neat chip amplifiers and other audio projects
|
| The Spud Amplifier Website - The amazing Spud vacuum tube amplifier |