The joy is that it is a so low noise preamplifier that it can operate with microphones of 25 ohm voice coil impedance.
A joy too for making or connecting an input transformer. The fact that the equivalent noise input resistance of V6 is so low combined with the fact that modern nanocrystalinne magnetic signal transformer cores have a huge inductance index mean that...
An input transformer can be wound with just a few turns for the primary and somewhat more for the secondary. And a 25 ohm pressure mic allows for this as its bass output will not drop by the relative low input inductance.
So transformers can be wound everywhere, at home, at the lab, on the beach...
Just 1 primary and 1 secondary. No stray capacitance and leakage inductance problems that may restrict bandwidth as the step up ratio can be small too. The V6 has a very small equivalent thermal input resistance. How small needs to be measured. Transformer winding wires can be thicker so less thermal noise too because of their lower resistance.
Everything being low impedance is low noise. And the joy is an electron tube extracting the subletest electron dance to the music while they travel from cathode to anode.
Reference:
Pleiades V6 schematic
No comments:
Post a Comment