DC power into AC input?

[Count Yorga]

I have some audio components I wish to combine. A preamp board, power amp board, and a couple of other components. The preamp and power amp boards have integrated rectifiers and filters. Other components require a DC input. It is all 12 volts. I wish to use a Toroidal transformer. I have a power supply board comprising a rectifier and some nice quality filter capacitors. This will increase voltage by 1.4 times, so a 9-0-9 transformer would result in just over 12 volts after rectification.

Can I run the resulting 12v DC into the amplifier boards, even though these are designed for AC input direct from the transformer? My understanding of rectifiers suggests yes, as only half the diodes would send the current to the power capacitors. But I'm not sure...

Would this be detrimental to the sound quality? Would it all explode and burn my house down?

My only other option seems to be to use two transformers, 9-0-9 rectified to 12 for the DC components, and 12-0-12 for the AC amplifier board.

Any advice would be very welcome, but please try to keep it as simple as possible.

Thanks

 

[rjenkinsgb]

It should work, but remember that the AC input boards would be operating on a DC level about 1.4x the ac input as well, with the correct supplies, so around +/- 17V.

If the other items are low current, I'd be tempted to use AC in to the board intended for it and pick off the DC from the smoothing caps on that, adding low drop out regulators and extra decoupling to the feed to the DC boards if they cannot take the higher DC voltage.

 

[alec_t]

My understanding of rectifiers suggests yes, as only half the diodes would send the current to the power capacitors.

But for a given load those diodes would be passing twice the current that they would in a full-wave bridge rectifier with an AC supply. So diode rating might be an issue.