Whether that happens or not depends on whether there is anything in between the op amp and the output stage. Those lower level stages can be designed to deal with the deep saturation without sticking to a rail for an undue length of time. I tend to stay away from the direct drive approach (ie, QSC) because it takes too many transformers to make. Can’t share supplies between channels. And if you’re already at two or three to make class H, I don't want to double it again. Or pay to have an 8 winding trafo made. More “normal“ topologies might have a sub-1-microsecond rail stick, and ill be damned if I can hear that. Lots of loop gain though - not good approaches for people who are allergic to NFB or can’t deal with oscillations on the first prototype.
QSC s floating masses circuitry is just a disaster, actually the real output is the floating mass with all the driving
circuitry floating as well, i remember a 2 x 200W/8R unit that was vastly outperformed by my simplistic 2 x 120W
mosfet amplifier using 6 transistors + 6 lateral fets, they were both tested by a bassist and driving a 38" speaker,
the QSC sounded as hollow as a barrel, even a much older quasi complementary Peavy CS400 was better.
circuitry floating as well, i remember a 2 x 200W/8R unit that was vastly outperformed by my simplistic 2 x 120W
mosfet amplifier using 6 transistors + 6 lateral fets, they were both tested by a bassist and driving a 38" speaker,
the QSC sounded as hollow as a barrel, even a much older quasi complementary Peavy CS400 was better.
That s an amplifiers US brand that is famed for some successfull yet infamous designs.
They designed a floating mass amplifier, basically a NE5532 driving a compound with gain, the OS was complementary
paralleled TO3s with the collectors as outputs being used as ground, hence the floating mass, this spared them insulating
the TO3s cases.
They designed a floating mass amplifier, basically a NE5532 driving a compound with gain, the OS was complementary
paralleled TO3s with the collectors as outputs being used as ground, hence the floating mass, this spared them insulating
the TO3s cases.
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