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    5v4GA Rectifier Tube

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    rodulfo23

    Posts : 2
    Join date : 2017-08-27
    Age : 53
    Location : Dublin, California

    5v4GA Rectifier Tube

    Post by rodulfo23 on Sat Oct 20, 2018 5:45 pm

    Hi! All,

    Is there anybody tried or are using this (5V4GA) rectifier tube on VTA ST-120 without issues? I have a couple of this
    which I got from Ebay 3 years ago and used them with Hagtech Clarinet Preamp and Cornet 2 phono preamp for less than 30 hours and found them better sounding than the stock 5Y3GT.

    Here is the link;(https://www.worthpoint.com/worthopedia/5ar4-rectifier-tube-nos-mil-philips-112414496)



    Thanks!

    Big Harry

    Posts : 18
    Join date : 2016-06-19

    Re: 5v4GA Rectifier Tube

    Post by Big Harry on Sat Oct 20, 2018 5:53 pm

    I don't recommend using a 5V4 to replace a 5AR4 in an ST120 as the 5V4 while they look similar to a 5AR4, they aren't, especially in the voltage rating department.
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    solderblob

    Posts : 45
    Join date : 2018-05-20
    Location : Placerville, California

    Re: 5v4GA Rectifier Tube

    Post by solderblob on Sat Oct 20, 2018 9:44 pm

    rodulfo23 wrote:Hi! All,

    which I got from Ebay 3 years ago and used them with Hagtech Clarinet Preamp and Cornet 2 phono preamp for less than 30 hours and found them better sounding than the stock 5Y3GT.

    Thanks!

    I'm using a Hagerman Cornet phono preamp (original version) which uses a 5Y3GT rectifier.  I recently decided to retube since it's been +/- 15 years since I built the amp.  I replaced the 12AX7s with some JJ tubes.  Very detailed but harsh.  So I put the original 12AX7s back in.

    So now I'm using the original tubes but with a JJ 5AR4 rectifier and it sounds OK, i.e., as before the retubing.  But would you recommend I try a 5V4?

    Dave

    Big Harry

    Posts : 18
    Join date : 2016-06-19

    Re: 5v4GA Rectifier Tube

    Post by Big Harry on Sun Oct 21, 2018 8:34 am

    Both the 5AR4 and 5V4 have a much lower voltage drop across them than the 5Y3 which will raise the B+ voltage maybe 20 or 30 volts. In a preamp, I would use a 5Y3 if that is what was specified for it. 5Y3's are readily available either NOS or good used and are fairly cheap.
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    solderblob

    Posts : 45
    Join date : 2018-05-20
    Location : Placerville, California

    Re: 5v4GA Rectifier Tube

    Post by solderblob on Sun Oct 21, 2018 9:29 am

    Big Harry wrote:Both the 5AR4 and 5V4 have a much lower voltage drop across them than the 5Y3 which will raise the B+ voltage maybe 20 or 30 volts. In a preamp, I would use a 5Y3 if that is what was specified for it. 5Y3's are readily available either NOS or good used and are fairly cheap.

    Thanks, good info.  Hagerman's instructions indicated that either 5Y3 or 5AR4 could be used.  I have the 5AR4 in there now so I'll use it for a while.  I can't really hear any difference.
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    Tubes4ever

    Posts : 121
    Join date : 2015-07-14
    Location : Star, Idaho

    Re: 5v4GA Rectifier Tube

    Post by Tubes4ever on Sun Oct 21, 2018 10:17 pm

    The 5v4GA is rated for 175mA of current output. The output tubes on the ST120 when biased at 50mA each is pulling 200mA total and that's not taking into account the current draw of the VTA driver board which is at least another 25mA.

    So no, you can't use the 5V4GA tube with a ST120 amp. At least and have the tube last very long.

    Jim McShane

    Posts : 207
    Join date : 2011-10-19
    Location : South Suburban Chicago

    Re: 5v4GA Rectifier Tube

    Post by Jim McShane on Tue Oct 23, 2018 7:35 pm

    rodulfo23 wrote:Hi! All,

    Is there anybody tried or are using this (5V4GA) rectifier tube on VTA ST-120 without issues? I have a couple of this
    which I got from Ebay 3 years ago and used them with Hagtech Clarinet Preamp and Cornet 2 phono preamp for less than 30 hours and found them better sounding than the stock 5Y3GT.

    Here is the link;(https://www.worthpoint.com/worthopedia/5ar4-rectifier-tube-nos-mil-philips-112414496)



    Thanks!

    The tube in the picture is NOT a 5V4GA. It is a 5AR4 JAN Philips tube. The US military had a need for 5V4GAs and Philips could not supply them (and didn't want to tool up to produce them) so they re-labeled some 5AR4 tubes as 5V4GAs. The 5AR4 can sub safely for a 5V4GA but not the other way around.

    A lot of people say it isn't a real 5AR4 - but it absolutely is. Compare the plates on the "5V4GA" to a 5AR4 and you'll see they are absolutely identical. Regardless of what is printed on it that tube is a 100% REAL 5AR4. You can use it wherever a 5AR4 is appropriate - including the ST-120.

    rodulfo23

    Posts : 2
    Join date : 2017-08-27
    Age : 53
    Location : Dublin, California

    Re: 5v4GA Rectifier Tube

    Post by rodulfo23 on Tue Oct 23, 2018 8:16 pm

    Thank you! Jim McShane for the very informative reply and info.
    Actually, I saw and took pictures of the Sylvania 5AR4/GZ34 etched on tube sold
    on Ebay as I write this reply. I just can't post the pictures. It appears the same
    plate and construction as the Philips ECG "mislabled" as 5V4GA.

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