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    rectifier tubes for VTA ST70

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    tubenutr

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    rectifier tubes for VTA ST70

    Post by tubenutr on Thu Dec 22, 2016 11:37 pm

    I'm sure this topic has been beaten to death, but.............................
    What rectifier tubes can be used in the above mentioned amp.

    Thanks, Mike
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    peterh

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    Re: rectifier tubes for VTA ST70

    Post by peterh on Fri Dec 23, 2016 5:44 am

    tubenutr wrote:I'm sure this topic has been beaten to death, but.............................
    What rectifier tubes can be used in the above mentioned amp.

    Thanks, Mike
    Any 5AR4 / GZ34 will do.

    So will a number of others that might or might function is intended.
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    Bob Latino
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    Re: rectifier tubes for VTA ST70

    Post by Bob Latino on Fri Dec 23, 2016 6:14 pm

    You can also use a 5U4 tube rectifier in the VTA amps. There will be a slight loss of power by the use of a 5U4 but the amp will work fine ..

    Bob
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    tubenutr

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    rectifier tubes for VTA ST70

    Post by tubenutr on Fri Dec 23, 2016 7:01 pm

    Thanks Bob.
    Just wanted to know.

    Mike
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    Dave_in_Va

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    Re: rectifier tubes for VTA ST70

    Post by Dave_in_Va on Fri Dec 23, 2016 7:25 pm

    High quality NOS 5U4s are widely available at very reasonable prices (like 1/3 - 1/4 that of a 5AR4).
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    Tubes4ever

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    Re: rectifier tubes for VTA ST70

    Post by Tubes4ever on Sat Dec 24, 2016 12:33 am

    And a 5U4 is notably longer lived than a 5ar4. As Bob noted, your B+ will be a bit lower than with a 5ar4 / GZ34. With a 5ar4 I get about 425 volts with a wall voltage of 120V. I get about 380V with a 5U4. You won't notice the difference unless you play your system really loud.

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