Hi,
to ACD:
Well the unit is part of a sub-bas speaker, so never will there be another speaker connected.
to unclejed613:
can you explain me your comments:
1. "one output stage drives the speaker, and the other moves the ground reference from rail to rail"
How do the Fet's Q12, 15 knows when to switch (or conduct)?
Is it due to the raise in voltage on the input of the opamps caused by the signal delivered to the speaker coming from Q14, Q17?
If that's the case it looks fasinating. Do you know more on that subject?
2. "because the speaker is coupled through the power supply caps."
I don't understand. Assume one of the bjt's (Q14, Q17) is dead and shorted. The full supply voltage is then over the speaker. But maybe then Q3 or Q1, depending on wich BJT (Q14, Q17) died will be switched off and hence switches of the Fet's via U1.
What makes the speaker survive such a situation?
Still bizare but worth thinking about it.
Thanks, Tarzan
to ACD:
Well the unit is part of a sub-bas speaker, so never will there be another speaker connected.
to unclejed613:
can you explain me your comments:
1. "one output stage drives the speaker, and the other moves the ground reference from rail to rail"
How do the Fet's Q12, 15 knows when to switch (or conduct)?
Is it due to the raise in voltage on the input of the opamps caused by the signal delivered to the speaker coming from Q14, Q17?
If that's the case it looks fasinating. Do you know more on that subject?
2. "because the speaker is coupled through the power supply caps."
I don't understand. Assume one of the bjt's (Q14, Q17) is dead and shorted. The full supply voltage is then over the speaker. But maybe then Q3 or Q1, depending on wich BJT (Q14, Q17) died will be switched off and hence switches of the Fet's via U1.
What makes the speaker survive such a situation?
Still bizare but worth thinking about it.
Thanks, Tarzan