Q What is the difference between a hybrid amplifier and a tube amplifier?
A Tube amplifiers use pure tube circuitry for the entire signal path. This provides the warm, agreeable sound quality associated with tube electronics.
But a full tube amplifier is expensive to manufacture, consumes a lot of power and power output is typically much lower than a solid-state amplifier of comparable price. It's these drawbacks (as well as reliability and the necessity of changing tubes) that led to the transition to solid state.
A hybrid amplifier combines tube circuitry with solid-state transistor circuitry. The idea behind a hybrid amplifier is to give you the best of both the tube and transistor worlds, combining the warm, natural sound of tubes with the high power of solid state at a lower cost than would be possible using all tube circuitry.
One type isn't necessarily better than the other. It depends on the amplifier, as well as the speakers, because some speakers match poorly with anything fewer than 100 watts.
That said, tubes tend to provide more real-world power than their ratings, meaning a 20-watt tube amplifier will perform like a 50-watt solid-state amplifier when paired with speakers that are not difficult to drive.
Not long ago, tube audio would be too expensive and esoteric of a subject to find its way into my column, but that has changed. People are rediscovering tubes in the same way they are rediscovering vinyl records. Tube components are popping up everywhere at many price points in all kinds of products -- from headphone amplifiers to iPod docks, as well as amplification for home sound systems.
A wide variety of affordable tube amplifiers and preamplifiers from China are now being sold online and in audio stores. Many of them perform exceptionally well, as well as being works of art in their own right.
