are you allowing for 3A bias at +-24Vdc from each half of the balanced amplifier?
i.e. 288W dissipation per channel.
3A bias gives ~ 6Apk of ClassA and results in 36W of ClassA into 2r0. This when feeding a 4r0 load from the two halves of the balanced is roughly 72W of ClassA into 4r0. Double the power into double the load impedance.
Working back from your 200W into 4r0 balanced, needs 100W into 2r0 from each half.
That requires a ClassAB output of 20Vpk and 10Apk. Probably a sensible target from +-24Vdc rails biased to a total current of 6A.
i.e. 288W dissipation per channel.
3A bias gives ~ 6Apk of ClassA and results in 36W of ClassA into 2r0. This when feeding a 4r0 load from the two halves of the balanced is roughly 72W of ClassA into 4r0. Double the power into double the load impedance.
Working back from your 200W into 4r0 balanced, needs 100W into 2r0 from each half.
That requires a ClassAB output of 20Vpk and 10Apk. Probably a sensible target from +-24Vdc rails biased to a total current of 6A.
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beetle. (bias x2) x (bias x2) x impedance /2.
so say 2A bias. it is 4 x 4 x 2 / 2 = 16W class A at 2ohm
or 64 W @8ohm
So ~3A bias 24V rails then. I would assume that Modushop 5U 500 has not the right sinks for 576W per channel. Or does it?
1kva 18V toroid will be costly. Any good source in Europe?
I would expect a total power of up to 200W in 4 ohm Class B and 36W class A. Right?
32 watts ...
are you allowing for 3A bias at +-24Vdc from each half of the balanced amplifier?
i.e. 288W dissipation per channel.
3A bias gives ~ 6Apk of ClassA and results in 36W of ClassA into 2r0. This when feeding a 4r0 load from the two halves of the balanced is roughly 72W of ClassA into 4r0. Double the power into double the load impedance.
Working back from your 200W into 4r0 balanced, needs 100W into 2r0 from each half.
That requires a ClassAB output of 20Vpk and 10Apk. Probably a sensible target from +-24Vdc rails biased to a total current of 6A.
Aren't the speakers seeing the double voltage when bridged?
Aren't the speakers seeing the double voltage when bridged?
yes,.............correct
how does knowing that help you?
Do you understand how an amplifier works?
Do you know the difference between ClassA operation and that for ClassAB?
Do you know how a bridged and balanced amplifier operates?
Bridging means that one amp is inverted or the signal. Current will remain the same but voltage is double.
Besides this a little, still learning. In this case we have a push pull amp. In this particular F5 design the first stage is splitting the signal in two halves. One inverted. The F5 is class A up to the bias. Then it transitions to class B. I think this describes it well: Push pull amplifier, working and theory. Class A , Class B , Class AB circuit diagram
Still learning.
Besides this a little, still learning. In this case we have a push pull amp. In this particular F5 design the first stage is splitting the signal in two halves. One inverted. The F5 is class A up to the bias. Then it transitions to class B. I think this describes it well: Push pull amplifier, working and theory. Class A , Class B , Class AB circuit diagram
Still learning.
Me no clue, no.
bottom line. i will not advice you to build a balanced version. for many reasons.
1. 4 ohm speakers is not a good load for it.
2. it is hard to build.
3. it demands a good match between the 2 amps.
4. it demands 4 times the output fets.
5. it is never been done. and a exact schematic do not exist yet.
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I did try BBQ-ing the dead fets at the end of my last backyard BBQ to make sure they were really toasted. The smell certainly was not fun especially the significant half's lookAll true. I believe you rea need to burn at least a couple of transistors before your having fun
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