Vintage McMartin Mono Power Amplifiers?

Discussion in 'General Audio Discussion' started by CDELON, Oct 11, 2018.

  1. CDELON

    CDELON Active Member

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    Are these Amps any good for Home audio?
     

     

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  2. 604man

    604man Super Member

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    I had a pair with KT 66 tubes , sold them to a friend back in the 70's
    wish i still had them.
     
  3. Pio1980

    Pio1980 AK Member Subscriber

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    They were located in Omaha and made distribution system amps for Muzak Corp.
     
  4. CDELON

    CDELON Active Member

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    The amps I'm looking at are LT3500D. They are not pretty. They have a open design.A floor mount type frame. Open bottom and cooling blade on top. From my understanding, they work. 350 watts. Cant find a lot of info on them.
     
  5. toxcrusadr

    toxcrusadr Omelette au Fromage Subscriber

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    Well post some pictures man! :D

    It mostly depends on the iron - were they really full range or are they a midrange-heavy PA amp? Hi fi was not really needed to distribute Muzak. BUT they could be fantastic too. :dunno:
     
  6. KentTeffeteller

    KentTeffeteller Gimpus Stereophilus! Subscriber

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    They were good enough for driving control room monitors in AM and FM broadcast stations, Muzak, other background music services, and more than good enough with efficient speakers for HiFi use.
     

     

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  7. JoeESP9

    JoeESP9 ESL's & tubes since 83

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    What do those things use for output tubes and how many per amp. 350 Watts is an awful lot for any amplifier from that era.
     
  8. CDELON

    CDELON Active Member

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    Im considering using them as mono blocks. I have access to two of them. I will need to pick up a pre-amp. The pic has a cover which mine does not. It does have a 8 ohm connection.
     

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  9. Pio1980

    Pio1980 AK Member Subscriber

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    Those what I thought. If working, overhaul should amount to a recap and checking all resistors against stated value and replacement of the drifters.
     
  10. JoeESP9

    JoeESP9 ESL's & tubes since 83

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    My mistake. I thought they were tubed amplifiers.
     
  11. CDELON

    CDELON Active Member

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    I looked at them again. The only connections were 70v, 25v and 1.5 ohm. They did not have the 8ohm connection like the pic I found and posted.
     

     

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  12. toxcrusadr

    toxcrusadr Omelette au Fromage Subscriber

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    We both did, it was the post early in the thread mentioning KT-66 outputs that led us in that direction.
     

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