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Rewording my confusion...

When that variable dead key is turned down, the voltage at the regulator is obviously lower. What happens when the dead key is turned down so that the collector is lower than mid-rail? The audio coming in is now trying to drive the regulator more negative on negative peaks than it does positive on positive peaks because it is biased below mid rail. Simply attenuating negative peaks does nothing for the positive peaks that now need to work harder to push the regulator from, say, 3v to 12v, instead of from 6v to 12v.

So, if the audio limiter only controls negative peaks, I have to assume the D42-R122 path acts as a current source on negative peaks, both engaging the limiter and charging the coupling capacitor at the same time, on the first strong negative peak, and the effect of charging that bypass capacitor is to raise the bias until the audio no longer draws current through D42. Am I understanding the function of that D42 path correctly?

<blockquote data-quote="brandon7861" data-source="post: 825695" data-attributes="member: 53724">Rewording my confusion...When that variable dead key is turned down, the voltage at the regulator is obviously lower.&nbsp; What happens when the dead key is turned down so that the collector is lower than mid-rail?&nbsp; The audio coming in is now trying to drive the regulator more negative on negative peaks than it does positive on positive peaks because it is biased below mid rail. Simply attenuating negative peaks does nothing for the positive peaks that now need to work harder to push the regulator from, say, 3v to 12v, instead of from 6v to 12v.So, if the audio limiter only controls negative peaks, I have to assume the D42-R122 path acts as a current source on negative peaks, both engaging the limiter and charging the coupling capacitor at the same time, on the first strong negative peak, and the effect of charging that bypass capacitor is to raise the bias until the audio no longer draws current through D42.&nbsp; Am I understanding the function of that D42 path correctly?</blockquote>

[QUOTE="brandon7861, post: 825695, member: 53724"] Rewording my confusion... When that variable dead key is turned down, the voltage at the regulator is obviously lower. What happens when the dead key is turned down so that the collector is lower than mid-rail? The audio coming in is now trying to drive the regulator more negative on negative peaks than it does positive on positive peaks because it is biased below mid rail. Simply attenuating negative peaks does nothing for the positive peaks that now need to work harder to push the regulator from, say, 3v to 12v, instead of from 6v to 12v. So, if the audio limiter only controls negative peaks, I have to assume the D42-R122 path acts as a current source on negative peaks, both engaging the limiter and charging the coupling capacitor at the same time, on the first strong negative peak, and the effect of charging that bypass capacitor is to raise the bias until the audio no longer draws current through D42. Am I understanding the function of that D42 path correctly? [/QUOTE]

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