passive preamp - Transformer coupling

Discussion in 'DIY Discussion' started by dreftar, Mar 30, 2007.

  1. dreftar

    dreftar

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    Ive been hearing a lot about Promitheus and other Transformer controlled Volume pre amps etc. Seems to be something of a fashion. Anyway I wondered if the gains in fidelity from those that like these pre amps may not exactly be coming from the way the attenuation is applied but rather from the isolation properties of the transformer. It could possibly be a lowering of the noise floor that leads to an apparent benefit in fidelity. There is also a trend at the moment towards using balanced feeds from source to pre then on to power amp like what they do in studio applications. The benefit of this way of interconnection is also in lowering the noise floor. It has been argued that the best HiFi set up is one that allows you a musical experience at comfortable living room volume level. I suspect that the best equipment has least noise in the electronics. Bearing this in mind I am considering a passive pre amp that uses a stock standard Alps Blue (10K Log), a source selector and two 1: 1 transformers on the input from the source. Can anyone offer any advice regarding which and where to source these transformers. They will have to be of high quality and wide bandwidth.
     
    dreftar, Mar 30, 2007
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  2. dreftar

    anubisgrau

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    you can buy transformers from nicholas who builds promitheus.

    there are different TVCs out there and there are different sonic results. AFAIC, i can't wait for a day when the S&B monopoly on transformers would be gone. i think their design of transformers is compromised due to production restrictions. better sonic results could be easily achieved with a different core geometry and another size. i know it is not easy to find someone to custom built the right xformers along the right lines, but if you search for an absolute in this sport, nothing is impossible. i just wouldn't stop at what MFA, bent or django have offerred as "the best from the TVC world", based on S&B TX-102.
    my 3 cents.
     
    anubisgrau, Mar 31, 2007
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  3. dreftar

    themadhippy seen it done it smokin it

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    why not wind your own?
     
    themadhippy, Mar 31, 2007
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  4. dreftar

    anubisgrau

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    it's not easy, but it is definitely worth of paying someone to do it according your instructions. find good cores, they have to be double-C, big enough, buy a good copper wire for this, and expirement to get the best balance between windings and core (read: the best sound).... it is not an easy job but i think some real TVC enthusiasts can make wonders out if this.
     
    anubisgrau, Mar 31, 2007
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