Using Luhndahl for Parafeed

Discussion in 'DIY' started by Cspirou, Oct 24, 2015.

  1. Cspirou

    Cspirou They call me Sparky

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    First here is the datasheet for a Luhndahl transformer.

    http://www.lundahl.se/wp-content/uploads/datasheets/1620_3_7_9202.pdf

    If I am reading the datasheet correctly the way push-pull transformers and single-ended transformers are wound are identical. The difference between them is how the taps are wired together and that SE transformers have a larger gap. From what I know about parafeed is that they are the same as a regular SE transformer but without a gap.

    Does this mean I can use their PP transformers but configure it as a SE transformer to use as a parafeed transformer?
     
  2. dsavitsk

    dsavitsk Friend

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    Yes. You can also order most Lundahls with a gapless option which increases the inductance if you need it. There is some argument that a small gap is actually beneficial, however, as it is said to linearize the transformer. The best person to ask about this is probably Kevin @ K&K.
     
  3. Cspirou

    Cspirou They call me Sparky

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    The spec sheet says that push pull still has a very small gap. I'll ask Kevin what my best option would be.
     
  4. dsavitsk

    dsavitsk Friend

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    Are you looking for headphones or speakers? For phones, the linked transformers would not be my first choice.
     
  5. Cspirou

    Cspirou They call me Sparky

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    The link wasn't specific to any particular project. I was mainly trying figure out the differences between a PP and an SE Luhndahl transformer and if they can be used for parafeed. Luhndahl has these complicated transformer wiring schemes for several transformers and the datasheet was only posted as an example of the wiring. I wasn't really trying to imply that I was planning on using that exact transformer.

    Eventually I would like to build a SE speaker amp and a SE headphone amp. Parafeed is a major curiosity for me so I am trying to find sources for parafeed transformers and was just wondering if a Luhndahl PP transformer would fill that role.
     

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