That's a very common power supply design, but it depends on the actual board design.
How much current do you need?
Is there room for heatsinks on the diodes?
Are the traces big enough?
Of course if you put it all together "point to point", with thick wires and heatsinked rectifiers, it's a non-issue. Your ripple will be determined by how much current you draw vs how much capacitance you have, you're going to want quite a bit of capacitance.
How much current do you need?
Is there room for heatsinks on the diodes?
Are the traces big enough?
Of course if you put it all together "point to point", with thick wires and heatsinked rectifiers, it's a non-issue. Your ripple will be determined by how much current you draw vs how much capacitance you have, you're going to want quite a bit of capacitance.
Yes - might be worth investigating making slightly better use of the power supply by running 3 of the chips with an inverted signal (or making them inverting). Peak currents are usually rather asymmetric so by having half the amps running inverted both capacitors get to provide the peak current rather than just one.
Not necessarily. Consider making a separate power supply for each channel. While it'll cost a bit more (depending on transformer costs), you won't have to deal with large amounts of power in one place.
Also, what impedance are the speakers you are driving with this amp?
It will cost quite a bit more than a single unit. Then the inrush current from six power supplies all being switched on together won't be too pretty
The advantage I can see from doing all monoblocks is it makes the grounding easier. But I think it won't give such a good bang-for-the-buck as the single higher power supply. The 2kW figure is only extreme peaks, assuming that all channels receive the same peaking signal in phase. Seems jolly unlikely to happen in practice.He has two PA150's. That would be 2 power supplies. If he goes with something like 70% max design factor, would it cost more for a single 1400VA transformer, or a pair of 700VA transformers? At these sizes, a pair might be cheaper. Then consider higher power diodes, larger capacitors to handle the current and thicker wires to connect it all together with the single large supply version.
Personally I think that's a bit much anyway. I would go for a pair of 330VA - 500VA transformers and call it a day.
Personally I think that's a bit much anyway. I would go for a pair of 330VA - 500VA transformers and call it a day.
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Aha, thanks, I'd missed that important detail
Definitely the two will cost more. Recently I bought one 1kVA and two 500VA transformers, I think the pair of 500VA cost about 30% more than the single 1kVA. I can't remember the exact prices but I do recall which was more.
I think it mainly depends on what signals are being sent through these 6 channels. If its a single 5.1 surround system for example then the sub channel needs the most and will be underpowered here - the rears don't do much most of the time.
<edit> just clicked his original link and found that its a paralleled design, 150W per channel. I suggest a single 625VA transformer and run one channel out of phase.
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I'm guessing that your power supply probably only really needs to be able to supply the max AVERAGE power that could be drawn, plus some over-design factor. Capacitors should/must then be able to supply the peaks when needed. And those will probably mostly be from the capacitors that are very local to each chipamp, at least for the leading edges of the peaks, since the conductor inductance will slightly delay the fast current demand responses from the farther-away main smoothing caps, anyway.
A new question?
What size of transformer do I need to power 6off 3886?
The maximum output from a 3886 is ~68W sinewave.
The maximum output from 6off 3886 is ~408W.
The maximum total ClassAB power that can be supplied by a 500VA transformer is from 250W to 500W. Any more power and the transformer may run a bit hot, any less power and there is too much money spent on the transformer for a small increase in amplifier performance.
The maximum power of 6 off 3886 fits nicely in the 500VA power range.
What size of transformer do I need to power 6off 3886?
The maximum output from a 3886 is ~68W sinewave.
The maximum output from 6off 3886 is ~408W.
The maximum total ClassAB power that can be supplied by a 500VA transformer is from 250W to 500W. Any more power and the transformer may run a bit hot, any less power and there is too much money spent on the transformer for a small increase in amplifier performance.
The maximum power of 6 off 3886 fits nicely in the 500VA power range.
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