Three years ago I build the first version of Nocturne – a transformer coupled tube headphones amplifier – equipped with 6C45p triode and then last year a second version with a more performing ( and more gain ) D3a triode strapped, both intended to drive with excellent performance a AKG K550 back closed headphones ( 32 ohms, 114 dB sensitivity ). A few months ago I got to try a planar magnetic open back…
By Enzo Grazioso