Station 6 Preamplifier and Monitor Controller
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Clipping characteristics, input preamp
The preamp circuit shows excellent clipping characteristics. When the amp clips, there is no bouncing, ringing, pumping
etc. There is just regular and plain clipping. A closer look at the leading edge of the clip shows that there is no overshoot
and no recovery delay. There is only instant clipping and instant release.
Observe that the output level is +28 dBu, so most equipment connected to the amp have already gone into clipping at this
level. The input clipping always occurs at a 10 dB higher level than the output clipping, thus the input clipping is always
masked by the output clipping. Input clipping cannot be transferred to the output.
Impulse response, input preamp
The above snapshots show the ideal step impulse response of the preamp. When subjected to a steep transient (in this
case a step impulse with 5 nsec rise time), there is no ringing and no overshoot. There is only total control. The amp does
NOT produce any signal itself when subjected to transient material. It does not add anything. It stays true to the source!
A closer look at the leading edge of the step impulse shows that there is absolutely no ringing or overshoot. Observe that
although the amplitude of the step impulse is +20 dBu, the circuit does NOT go into slew rate mode. The curve remains a
true exponential.
The output voltage swings 20 Volts in less than 1 usec. Rise time (10/90 % of the amplitude) is approx 0.6 usec
