'Seems like some folk need to read up on the original Quad "current dumping" amplifiers like popular models 405,306,606,909. This design by Apex is an interesting variation and no, McFender, they are suitable for hi-fi and have been highly regarded since the 1970s.
They are feed-forward error correcting designs, based on a small class A amp which is augmented by a big class "B" amp. This "dumps" output current to the load according to the error sensed in an LCR bridge network at the output, as the small amplifier tries to drive the heavy speaker load. This has little to with speaker back-emf, though it is often suggested.
Read the early posts by Jan Didden and others here.
They are feed-forward error correcting designs, based on a small class A amp which is augmented by a big class "B" amp. This "dumps" output current to the load according to the error sensed in an LCR bridge network at the output, as the small amplifier tries to drive the heavy speaker load. This has little to with speaker back-emf, though it is often suggested.
Read the early posts by Jan Didden and others here.
There seem to be some confusion over the term Current dumping. The amplifier described in post 1 is a Quad type error feedforward amplifier described by Quad as a Current dumping amplifier with the unbiased output stage and the output bridge circuit, the amplifier in post 25 and its derivatives are not
Stuart
Stuart
post1 is apex circuit.
post25 does not have a circuit to refer to.
405man,
what are you referring to as Quad style current dumping and "the others"?
post25 does not have a circuit to refer to.
405man,
what are you referring to as Quad style current dumping and "the others"?
Quads original current dumping is one thing, but other versions that essentially does the same exists just as well. The dumpers can be biased as well making a class A amplifier controlling class A-B BJT dumpers.
I this thread I find the last Apex circuit rather interesting as it features an inverting OPS with a local feedback loop around it. A concept that could be well worth visiting
I this thread I find the last Apex circuit rather interesting as it features an inverting OPS with a local feedback loop around it. A concept that could be well worth visiting
My mistake, it should be post 21 and the subsequent designs in posts 79 & 80 The attached link in post 4 describes the Quad 405 current dumping amplifier which uses error feedforward using a class A amplifier and an unbiased output stage. The amplifiers described in post 21, 79 & 80 do not conform to this topology, this is a link
G. Schmidt "Currenl dumping amplifier" - DIY - Audiostereo.pl
to an elector design which is similar to post 21 but using the Quad topology
Stuart
G. Schmidt "Currenl dumping amplifier" - DIY - Audiostereo.pl
to an elector design which is similar to post 21 but using the Quad topology
Stuart
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can i used this protect for B500 amp sir Mile?
No, use preotect with NE555 it's also simple.
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