Comparison of a one electron tube to a one transistor power amplifier ,Pleiades experiments

At your risk. All safety precautions for voltage or current should be followed.


Now that the WE417 sound louder than first tests by increasing anode voltage, anode current and adding a Sowter output trasformer a perhaps more meaningful comparison can be made.



See earlier today's post.
https://euroelectron.blogspot.com/2019/06/we417a-5842-electron-tube-with-bigger.html


Summary:


The Pleades BD139 one transistor power amplifier sounds so far louder than the (comparable power?) Pleiadss WE417A one electron tube power amplifier.


The electron tube amplifier sounds more smooth. The transistor one sounds louder but harsher in perhaps a more metallic sense. Both amps are no feedback and sound very dynamic with transient detail. Not fair for the transistor is that at the moment the output trasformer is made of a power transformer core.


A much more meaningful comparison would be to use the same core for both devices operating in class A. For example winding a 60Ω? winding to the Sowter air gaped transformer and connecting such winding to the transistor.


A Carlos Jobim is used for this test.


On Ray of Light - Madonna it is felt that the one transistor amplifier sounds better as the electron tube one sounds running out of steam at bass as well as more confused in bass. Perhaps harsher in bass too.


Both amplifiers are low power, less than 1W(?) yet loudness can be felt to be enough around many rooms at Pleiades.


One drive unit fullrange speakers are used. Pleiades linoleum Auratone 5C type cube near field monitor speaker with Tesla TVM ARX 130-20/4 5in 4Ω or Zeiss Ikon typ:31-06 which is a 20in x 20in baffle with a DEW 7in drive unit. The latter is more sensitive ie plays louder.