Krell PMA 5 Recap.

Discussion in 'Solid State' started by vishalk, Dec 13, 2018.

  1. vishalk

    vishalk AK Subscriber Subscriber

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    Just picked this up to match my krell ksa 100, any tips on recapping this beauty?

    Should i just replace every capacitor in the preamp or just the ROE ones?
     

     

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  2. FootFungus

    FootFungus Super Member

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    I'd change out all the electrolytics - the Elko axials in the power supply and the ROE bakelites. It looks like there might be Roederstein axials in the center of the pre as well.
     
  3. mondialfan

    mondialfan Active Member

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    Interesting that you can see a bit of the early Aragon lineage in that PAM-5 external power supply. Same encapsulated transformer and similar layout with the same bridge rectifier positioned up by the transformer, the pcb even appears to be of a nearly identical dimension. The Aragon used a Zener emitter follower regulator versus the early PAM-5's non-reg PS, but the similarity is definitely there. The Aragon IPS boards in my picture are from the first gen of their external PS's dating to the late 80's. Later PAM's supposedly had a regulated ext. PS so I wonder how similar that one was to the Aragon IPS.

    IPS_early.jpg
     
  4. FootFungus

    FootFungus Super Member

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    The PAM regulated supplies were a bit different than your IPS pictures. They used TO-3 transistors for the regulators, but I think similar scheme. The transformers were not encapsulated.
     
  5. mondialfan

    mondialfan Active Member

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    The later IPS switched to a cheaper non-encapsulated transformer as well. I stumbled across a picture online of one of the later regulated PAM supplies, yeah a bit different look to them with the TO-3's in there.
     

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