Yet another dreadnought question re: transformers.

tygr1955
tygr1955 Posts: 45
edited May 2014 in Vintage Speakers
Please don't bash me. This is a serious question.

Why the need for such a high end transformer just for isolation? What should the secondary voltage be? OK, that's two questions, but please help me to understand.
Post edited by tygr1955 on

Comments

  • F1nut
    F1nut Posts: 50,554
    edited April 2014
    Why the need for such a high end transformer just for isolation?

    Mo better sound. The goal is reducing noise, so the better the transformer, the cleaner the signal. I should add, the amp rating is also important, the higher the better.
    What should the secondary voltage be?

    The same as the primary. You want a 1:1 ratio.
    Political Correctness'.........defined

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  • DarqueKnight
    DarqueKnight Posts: 6,765
    edited April 2014
    tygr1955 wrote: »
    What should the secondary voltage be?

    SDA-Dreadnought-Isolation-Transformer-Output-Voltage-Balance
    Proud and loyal citizen of the Digital Domain and Solid State Country!
  • gimpod
    gimpod Posts: 1,793
    edited April 2014
    Question #2: The short answer is 115 volts.

    Here's a link to a spec sheet for the Avel Lindberg Y23 Range Transformers the Y236906 (800VA) is near the bottom.
    “The two most important days in your life are the day you are born and the day you find out why.” ~ Mark Twain
  • tygr1955
    tygr1955 Posts: 45
    edited April 2014
    Thanks kids! That clears up a lot for me.
  • SciFiTom
    SciFiTom Posts: 58
    edited April 2014
    Gents, I see in Gimpod's link that Avel has a 1kVA isolation transformer, as well as the 800VA model originally used. Albeit not the same as the custom model obtained by DK, why was it not considered initially?
  • nspindel
    nspindel Posts: 5,343
    edited April 2014
    The Avel 1kVA isolation transformer is a minimum purchase of 10 units special order, whereas the 800VA is a stock item and you can purchase one unit. Many of us have used the 1kVA after organizing group-buys of 10 units or more. But unless there is a group buy in progress for you to participate in, you would need to use the 800VA.
    Good music, a good source, and good power can make SDA's sing. Tubes make them dance.
  • F1nut
    F1nut Posts: 50,554
    edited April 2014
    SciFiTom wrote: »
    Gents, I see in Gimpod's link that Avel has a 1kVA isolation transformer, as well as the 800VA model originally used. Albeit not the same as the custom model obtained by DK, why was it not considered initially?

    The stocked 1000VA transformer, part #Y236956 is not audio quality according to Melanie at Avel.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • SciFiTom
    SciFiTom Posts: 58
    edited April 2014
    Thank you, F1nut.
  • nspindel
    nspindel Posts: 5,343
    edited April 2014
    F1nut wrote: »
    The stocked 1000VA transformer, part #Y236956 is not audio quality according to Melanie at Avel.

    Correct. The part number for the audio quality 1000VA from A/L is AV-047548. Cost when ordering 10 pcs. was $268.43/unit back in 2012. This is for the "GOSS Band, Low Noise Design" specification.
    Good music, a good source, and good power can make SDA's sing. Tubes make them dance.
  • SciFiTom
    SciFiTom Posts: 58
    edited April 2014
    Oops. What would the current transformer recommendation be, at a reasonable price? The plitron? TCM?
    I occasionally think about getting the Wyred4Sound amp, which I expect would need the transformer.
  • nspindel
    nspindel Posts: 5,343
    edited April 2014
    Several threads have popped up about this recently. My advice would be to start a group buy. Avel makes it very easy for you. Collect the money and pay them, but they handle all of the individual shipments.
    Good music, a good source, and good power can make SDA's sing. Tubes make them dance.
  • F1nut
    F1nut Posts: 50,554
    edited April 2014
    SciFiTom wrote: »
    Oops. What would the current transformer recommendation be, at a reasonable price?

    The Avel Y236906 or see if there is interest in the AV-047548 as nspindel suggested.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • cerez
    cerez Posts: 1
    edited May 2014
    tygr1955 wrote: »
    Please don't bash me. This is a serious question.

    Why the need for such a high end transformer just for isolation? What should the secondary voltage be? OK, that's two questions, but please help me to understand.

    The transformer is the safest choice for the isolation and it depends upon your application also what kind of isolation we need. For applications where the large current back flow is expected the transformer is best choice as there is no connection between primary and secondary. Also for isolation we use the transformer with turn ratio 1:1 therefore ideally the secondary voltage and current will be same as primary.