- Feb 12, 2006
- 61,075
- 5
- 221,151
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
The short term point of diminishing returns is governed by the resistance/impedance of the output Zobel choke, emitter resistance and saturation resistance of the output transistors in the output stage (which at also in series with the load) at the point of clipping only.) The longer term PODR includes the transformer and diode bridge (which is also in series with the load)
Below the point of clipping, there will be (or should be) no difference, because the on resistance of the output transistors will dominate.
IMO, it's an excercise in futility once past the point of diminishing returns (which is likely to be somewhere around 10,000uf, but what do I know, right?
The danger of hanging so much capacitance onto the power supply is saturating the core of the transformer for a longer period of time at turn-on which results in excessive inrush current (likely will not pass safety certification), damage to the power switch contacts, the destruction of any speaker connected if there was a single rail shorted device fault, and in the event of a 2 rail device failure, likely catastrophic damage to the PCB and other components due the the dissipation of stored energy.
No real engineer in their right mind would design/build an amp like this. An otherwise simple repair would become a PCB replacement any time a pair of output transistors failed shorted rail to rail (in addition to the speaker damage liability from a single rail fault).
Sorry, this gets an "eyes roll" from me.
Below the point of clipping, there will be (or should be) no difference, because the on resistance of the output transistors will dominate.
IMO, it's an excercise in futility once past the point of diminishing returns (which is likely to be somewhere around 10,000uf, but what do I know, right?
The danger of hanging so much capacitance onto the power supply is saturating the core of the transformer for a longer period of time at turn-on which results in excessive inrush current (likely will not pass safety certification), damage to the power switch contacts, the destruction of any speaker connected if there was a single rail shorted device fault, and in the event of a 2 rail device failure, likely catastrophic damage to the PCB and other components due the the dissipation of stored energy.
No real engineer in their right mind would design/build an amp like this. An otherwise simple repair would become a PCB replacement any time a pair of output transistors failed shorted rail to rail (in addition to the speaker damage liability from a single rail fault).
Sorry, this gets an "eyes roll" from me.
