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In the Forum: Audio Discussions
In the Thread: It’s mad, mad, mad... electricity.

Post Subject: Funny electricityPosted by JOHNR on: 1/27/2016

I continue to be amazed at the varied views relating to BAD power at certain times of the day.
I broke with that 10 or more years ago in moving to amplifiers, line amps and DACs configured with switched mode supplies.

I not only keep my DAC permanently powered, I have people who permanently power their entire switched mode supported system.
In one case 4 years non stop.

Indeed Malaysian and Singaporean audiophiles have gone through the stages of battery powering and those to whom I asked the question of sonic quality said no, it does not work well. Many have also experimented with computer smsp modules but these are a waste of time due to noise and inadequate stability.

The simple solution for an iron transformer based SET B+ supply is to use a voltage doubler configuration. It suffers from a source impedance being higher than a bridge supply however, it is not affected by small frequency variations. Also It does not pass audio signals through the power transformer because it has no path. With SET being constant current in nature, the source impedance is not relevant.

For push pull it does not work precisely because of its higher source impedance. The output voltage will droop with increasing current.

I have done a lot of work on filament supplies and concluded that all supplies dump noise energy into the tube which will amplify it by a factor of at least 1. The solution has been to use SMPS techniques derived from either a 48 volt dc supply or 85 to 275 volt ac supply. I did make some 50 of the ac modules for local audiophiles and they did make a lot of difference.

The core problem of all supplies lies with their source impedance.
As an example batteries suffer from a changing impedance related to their state of charge.
AC supplies are dependent upon the impedance of the supply side transformer windings and of course, the cheap and cheerful aluminium connecting cables to the property itself.
Also, I would not expect any of the UPS type systems to be able to handle supply side harmonics, common mode noise (maybe) because all of these noise artifacts will pass right through.

John

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