LMA8 Mic/Line Preamplifier
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Technical section
Clipping characteristics
The LMA8 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 cutting edge of the clip can be seen on the right picture. Notice that
there is no overshoot and no recovery delay. There is only instant clipping and instant release.
This kind of clipping is barely audible on short transients. Note that the output level is +30 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
The above snapshots show the ideal step impulse response of the LMA8. When subjected to at 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 can be seen on the right picture. There is absolutely no ringing or
overshoot. Also, the amplitude of the step on the picture 20 dBu audio level, yet 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 600 nsec
