NO Ultra-Linear/Triode Operation – You do not want this mode of operation in your Tube Amp!
The Holy Grail is Pentode/Triode Pure Class A
No, we do not use ultra-linear/triode operation – Inferior for High End
Ultra-linear electronic circuits are those used to couple a tetrode/triode or pentode
vacuum-tube to a load (e.g. to a loudspeaker).
‘Ultra-linear’ is also known as ‘distributed loading’; a circuit technique patented by
Alan Blumlein in 1937. Ultra-Linear “distributed loading” was intended
for guitar amps, etc.
• In pentode or triode, in which the screen-grid is connected to a stable DC voltage so there are no signal
variations on the screen-grid (i.e. the screen-grid has 0% of the
plate’s output signal impressed on it), or
• In triode, in which the screen-grid is connected to the plate (i.e. the screen-grid
has 100% of the plate’s output signal voltage impressed on it), or
• a blend of triode and pentode, in which the screen-grid has a
percentage (between 0% and 100%) of the plate’s output signal impressed
on it. This is the basis of the Ultra-Linear “distributed load circuit”
and is seen as a form of feedback, which alters the behavior of the
electron stream passing from cathode to anode.
Ultra-linear introduces negative feedback, which squashes and compresses the sonic performance.
So the Pentode/Triode operation will yield a vastly superior response and
more of a “tactile” or SET sound, more of a three dimensional sonic
signature. Quite Superior!