IntroductionWhilst all of the other tests posted so far are looking for the best possible distortion and noise measurement, in this case we are going in the opposite direction and purposely trying to add distortion in the same way a tube circuit does.
MeasurementsIn the following tests we operate different tube profiles whilst keeping the grid bias constant. In all of these tests we are mimicking the way a tube Preamplifier behaves which is exposed to a full scale signal all of the way before the volume control which is unlike a Tube Power Amplifier where the distortion increases with increasing volume control !
- "Signal Tube" emulation mode distortion test at -3dBFS (https://analog-precision.com/forum/performance-and-measurements/tube-emulation-tests/msg51/#msg51)
- "Power Pentode" Tube emulation mode distortion test at -3dBFS (https://analog-precision.com/forum/performance-and-measurements/tube-emulation-tests/msg52/#msg52)
- "Power Triode" Tube emulation mode distortion test at -3dBFS (https://analog-precision.com/forum/performance-and-measurements/tube-emulation-tests/msg53/#msg53)
ConclusionThese are just three examples of what can be achieved with Tube Emulation as the grid bias control and amplifier type allows many different permutations of altering the tube linearity and hence the distortion profiles !! For tube and SET aficionados the pure 2nd harmonic distortion should be music to their ears !!