All Jfet Buffer SE Line Amp

This preamp is same as the All Jfet Buffer Line Amp except it is only for Single Ended input and output (RCA input/output sockets).  An old Alps volume ( 100K type A) is used at the input instead of step attenuator.

From the picture, you can see there is one single 25V x 2 30VA transformer and two Borbely low noise regulators and two buffer modules are used.  It is very simple but it sound also wonderful when driving a F5.

The FFT measurement show that the hum noise is very small and also distortion is very good at 0.0035% at 1Vrms output level.  At 10Vrms output, the distortion rises to about 0.009%.  Hum and noise is at about 1.2mVrms at maximum volume.

FFT output at 1V, 12k load lin

FFT output at 1V, 12k load log

FFT output at 10V 12k lin

FFT output at 10V 12k log

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