THOMAS MAYER NEW TOP OF THE LINE AMPLIFIERS


After the introduction of the 845 amplifiers with an indirectly heated driver, here is Thomas Mayer's new top of the line single ended 845 mono amps with a directly heated driver. The Elrog ER887 is a completely new tube type especially developed for these amps by Deutsche Elektronenröhren Manfaktur GmbH.

As 845 requires a large voltage swing at its grid an amplifier with all directly heated tubes would normally require minimum stages due to the low amplification factor of directly heated triodes.

The all-new ER887 is a big directly heated triode with thoriated tungsten filaments. No similar tube type was ever made so far. It shares the identical glass bottle/Jumbo 4 pin base as the 845 and operates at similar plate voltages.

You can see in the photo, that power supply uses a hybrid bridge with two ELROG ER274A and two 6AU4 TV dampers for the rectification of the plate voltage. The complete set of four chassis takes a whole square meter of floor space.


Link: here.