Triode / Ultralinear Switch
A triode/ultralinear switch selects how a tube amplifier’s output stage operates. It is a yes/no feature, not a power rating.
The switch changes electrical connections around the installed output tubes; you do not replace tubes to change modes. Triode and ultralinear describe two ways of operating those tubes, not two speaker connections.
Triode / Ultralinear Switch — Power Amp
For a power amplifier, triode mode generally provides less available output power than ultralinear. Check the rating for your chosen mode, tube configuration and speaker load. Do not carry over the ultralinear wattage or assume triode always delivers exactly half as much.
Before changing modes, follow the amplifier’s own operating instructions. Some designs permit switching while music plays; others require the power to be off. The mode names alone tell you neither how to use the switch safely nor which setting will sound better.
Sources
- CAD-50M MkII: output-tube operating modes — Cary Audio
- EVO power amplifiers: mode ratings and switching — PrimaLuna
- 120 Watt Monoblock: switching instructions — Manley Laboratories