This was done before listing to the Pleiades 2N3055
Signal path:
(Fame soundtrack CD, Ingenue - KD Lang CD) - Sony CD Walkman - amplifier under test - Zeis Ikon fullrnage baffle speaker or Pleiades linoleum Auratone 5C type fullrnage speaker - reverberant small room - listener's brain
Trying various output transformer secondary taps with the BD139 amolier it was found that louder did not mean better
More turn windings ie more output impedance gave a more smooth, bass, treble mid sound.
This agrees with the Nelson Pass paper on higher output impedance for driving fullrnage speakers.
The DL33 at 10mA sounded less loud but more civilized.
On both above cases the Zeiss Ikon speaker sounded much louder.
Then the 2N3055 was tried in a different room with tye Pleiades linoleum Auratone 5C type speaker, see next post.
Very nice sound.
It seems there is a lot of impedance mismatch as the 4Ω speaker voice coil is directly coupled to the collect.
Yet it sound nice and big.
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