Balanced power for CD players
http://www.diyhifi.org/forums/viewtopic.php?p=29458#p29458
See:jacco vermeulen said:
http://www.diyhifi.org/forums/viewtopic.php?p=29458#p29458
Re: Still getting 144VAC on secondary
OK, it sounds like you're finished. You're putting 120VAC across 1 & 6; 2 & 5 are jumpered and isolated; 7 & 12 are your new hot AC wires, and 8 & 11 are jumpered and grounded both to your outlet and device.
It sounds like it's working fine, that 144VAC measurement is is most likely high because your meter is a high impedance. I would give it a try now. If you are paranoid you can put a resistor across 7 & 12 and try to measure again.
hollowman said:
OK, it sounds like you're finished. You're putting 120VAC across 1 & 6; 2 & 5 are jumpered and isolated; 7 & 12 are your new hot AC wires, and 8 & 11 are jumpered and grounded both to your outlet and device.
It sounds like it's working fine, that 144VAC measurement is is most likely high because your meter is a high impedance. I would give it a try now. If you are paranoid you can put a resistor across 7 & 12 and try to measure again.
Results of balanced power experiment
Yup. A tech at TRIAD just informed me that 144VAC is to be expected if no load is connected. This is not stated in any of their literature or web site. So it's "safe" to try. I did and immediately noticed much-improved (overall) results from a stand-alone DAC, but degraded perf. from a small headphone amp. My PHILIPS CDB650 refused to start expect, weirdly, the IR remote LED on front panel was lit. The CDB650 does not have chassis ground -- nor a polarized plug -- and I'm not sure about how its own tranf. is config’d. When I plugged it back into a normal outlet, all was OK (not damaged, thank goodness!). Another Philips unit -- also w/o polarized plug and sans ground lug -- worked fine with balanced power.
I'll report back on the CDB650 once I determine its power scheme -- unless someone wants to save me the hassle and offer a solution 😉
leadbelly said:
Yup. A tech at TRIAD just informed me that 144VAC is to be expected if no load is connected. This is not stated in any of their literature or web site. So it's "safe" to try. I did and immediately noticed much-improved (overall) results from a stand-alone DAC, but degraded perf. from a small headphone amp. My PHILIPS CDB650 refused to start expect, weirdly, the IR remote LED on front panel was lit. The CDB650 does not have chassis ground -- nor a polarized plug -- and I'm not sure about how its own tranf. is config’d. When I plugged it back into a normal outlet, all was OK (not damaged, thank goodness!). Another Philips unit -- also w/o polarized plug and sans ground lug -- worked fine with balanced power.
I'll report back on the CDB650 once I determine its power scheme -- unless someone wants to save me the hassle and offer a solution 😉
Re: Results of balanced power experiment
That's because it has nothing to do with Triad. It's true about all transformers. Secondary voltage is a function of load.
As for why the Philips doesn't work, that might be because of a more serious problem: that transformer you selected is VERY small. The isolation transformer has to be sized for the current draw of the transformer of the you are plugging into it. This is a larger value than just what the circuit demands are, because the transformer is also drawing current to magnetize its core. You might try just reading the voltage on the secondary side of the isolation transformer when the Philips is plugged in.
hollowman said:
That's because it has nothing to do with Triad. It's true about all transformers. Secondary voltage is a function of load.
As for why the Philips doesn't work, that might be because of a more serious problem: that transformer you selected is VERY small. The isolation transformer has to be sized for the current draw of the transformer of the you are plugging into it. This is a larger value than just what the circuit demands are, because the transformer is also drawing current to magnetize its core. You might try just reading the voltage on the secondary side of the isolation transformer when the Philips is plugged in.
Re: Re: Results of balanced power experiment
Thx for that useful feedback!
Yes, indeed, the voltage drop on secondary WRT the Philips is ~92VAC. FYI, the other components noted earlier measure as follow when plugged into the small balanced Triad: DAC (116VAC); Headphone amp (123VAC). The small Triad, on its secondary, is only capable of putting out 0.11A series (0.22A parallel); balanced wiring is series.
The DAC, for which I noted overall beneficial sonic gains (imaging, detail, less grain), did suffer a bit WRT bass (depth/slam) and dynamics. That DAC, with its own toroidal trans., requires 0.09A. The Philips needs over 0.35A.
I also have the larger Triad you suggested, so I'll see how using that trans. further improves the DAC's fidelity...and affects the Philips CDP.
leadbelly said:
Thx for that useful feedback!
Yes, indeed, the voltage drop on secondary WRT the Philips is ~92VAC. FYI, the other components noted earlier measure as follow when plugged into the small balanced Triad: DAC (116VAC); Headphone amp (123VAC). The small Triad, on its secondary, is only capable of putting out 0.11A series (0.22A parallel); balanced wiring is series.
The DAC, for which I noted overall beneficial sonic gains (imaging, detail, less grain), did suffer a bit WRT bass (depth/slam) and dynamics. That DAC, with its own toroidal trans., requires 0.09A. The Philips needs over 0.35A.
I also have the larger Triad you suggested, so I'll see how using that trans. further improves the DAC's fidelity...and affects the Philips CDP.
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