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About Vytas

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  1. A novel way to massively improve the SQ of computer audio streaming
    A novel way to massively improve the SQ of computer audio streaming

    For anyone wondering about the HDPlex 400w LPSU here's the rail config.


    400W ATX LPSU has 3.3V/5V/12V/19V.  Four separate rails from the transformer.


    19V rail is powering the 19V XLR and 9V XLR.

    5V is powering the 5V XLR and ATX 5V

    12V is powering the 12V XLR and ATX 12V including CPU and PCIE

    3.3V is powering the ATX 3.3V.

  2. Wiring and connecting to Isolation Transformers
    Discussion of AC mains isolation transformers
    22 hours ago, tims said:




    Got a couple of noobish questions regarding grounded neutral secondaries and also balanced supplies that I hope someone can help me with: @One and a half, @zilch0md ?


    Just discovered my Topaz doesn't have a grounded neutral secondary (i.e. it's floating) and is currently supplying a low power intergrated DAC/amp and a separate music server which according to the info above is not ideal (Warning: Plug only ONE load into an Iso T with a floating neutral secondary). If I understand correctly the way to go is to ground the Topaz secondary neutral to enable more than one load to be connected for better performance?

    What if I convert my Topaz to a Balanced mode output; is a Balanced output configuration still good for using more than one load or should only a single load be used as per a floating neutral secondary?


    Second question: When in Balanced mode, does this mean the Topaz's output is reduced?  My stereo draws around 400-450VA which is close to the recommended limit for my 750VA Topaz and I'm concerned that switching to Balanced mode may not be ideal if output power may come down? I have 240v mains power in my country.


    Thanks for any replies.


    Hi tims!


    Unfortunately, I'm not able to go back and edit the post you are quoting:




    Quite some time ago, I updated the graphic to correct an error in my understanding, thanks to the teachings of John Swenson.


    The punchline is that Common-Mode noise is attenuated by Isolation Transformers, whether their secondaries have floating neutrals or grounded neutrals.


    Here's my current version of that graphic:




    ... as found on the first page of this thread at Head-Fi.org:




    In answer to your questions, I personally wouldn't bother to convert to balanced operation, even if it's possible and yes, for safety reason, you should not plug more than one load into a transformer with a floating neutral secondary.  I don't believe any Topaz units shipped with a floating secondary, so yours must have been modified.  I recommend you ground the neutral, but if you don't know how, you should get an certified electrician to do the work for you.   It's either that or just get another one and keep this one for powering a single DAC or any single audio component that uses a switch-mode power supply - both of which are suspect for backwashing noise onto the mains - where a floating neutral secondary can prevent that from happening.



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