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    Dyna PAM 1 (Reborn Transformer Implemented) Part 2

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    Mark Korda

    Posts : 23
    Join date : 2009-12-29

    Dyna PAM 1 (Reborn Transformer Implemented) Part 2

    Post by Mark Korda on Mon Mar 08, 2010 7:57 pm

    Hi,I finally figured out the images thing.The passive preamp here was designed by Jack Elliano who runs or owns Electra-Print Audio.The article was in AudioXpress Jan. 2005.All I did was to show an old junky Dyna-PAM-1,as old as I am still has some use,chassis,knobs,and faceplate.The 2 transformers were purchased from Electra-Print(electaudio@aol.com).They are the PVE-3's.If you build one,and don't have the article,Jack will draw you a simple schematic as he did for me.Here is what it looks like.inside final....I showed some stuff I got at the hobby shop.They had brass,wood(walnut),and plastic to cover unused holes.I made a little logo with the brass and model paint....logo.....the plastic stuck on with double stick tape....backand here is how it looks....cover on...This was a simple strait wire with gain idea,as I showed my first passive to show what more flexability the PAM-1 will have later.The holes and swiches are already drilled out and hide behind the plastic and wood for future use.In the schematic Jack drew out a additional out put for a subwoofer too.I had fun making this and think I'm running out of word space so,I will discuss how it sounds if anyone reads this....It has made me late for work every time I listen at night,thats how good it sounds......thanks Mark Korda(mark.korda@myfairpoint.net)

    Bob Latino
    Admin

    Posts : 2378
    Join date : 2008-11-26
    Location : Massachusetts

    Re: Dyna PAM 1 (Reborn Transformer Implemented) Part 2

    Post by Bob Latino on Mon Mar 08, 2010 10:30 pm

    Mark,

    It looks great ... I love seeing custom Dynaco type stuff. You took an old PAM-1 which many would pass on because it is monaural preamp and made something quite useful out of it .. Nice work ...

    Bob

    Mark Korda

    Posts : 23
    Join date : 2009-12-29

    Dyna PAM 1 (Reborn Transformer Implemented) Part 2

    Post by Mark Korda on Wed Mar 10, 2010 7:15 pm

    Here is some more info from Jack Elliano on the transformer implemented passive preamp.The transformers used step up the output from your cd player or high level source.The bandwidth of the trannies used was -1db from 6hz to 55khz.It is best to keep the output to the amp interconnect capacity around 50pf.With no power supply the design will have no power supply noise residue despite having gain.Normal listening levels ranged from 11 o'clock to 2 o'clock.Steel chassis give the best results absorbing stray magnetic fields from power transformers and chokes.Now,the sound.Jack wrote,the first thing you notice is a wide swing in dynamic range-very different from the CD player op-amp output.Second is a clean rich delivery of harmonics of strings and brass.Do not exceed 3V input or nickecore will saturate and distortion will occur at low frequencies.These were all quoted from AudioXpress from Jack Elliano....Mark Korda.

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