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    That Good Old Rectifier Sound

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    evgenibgr

    Posts : 12
    Join date : 2012-02-28

    Re: That Good Old Rectifier Sound

    Post by evgenibgr on Mon Nov 24, 2014 5:50 am

    sKiZo wrote:

    Ever think about adding some extra legs to help support all those MCaps on that driver board? lol!

    These m-cap of the driver board are silver-gold in oil. I think they not need to be strengthened.

    wgallupe

    Posts : 81
    Join date : 2014-05-18
    Age : 62
    Location : Central Mass.

    Re: That Good Old Rectifier Sound

    Post by wgallupe on Fri Nov 28, 2014 4:34 pm

    UPDATE: Earlier in this thread I had mentioned that the Philips 5R4GYS was working OK for almost a month in my ST120. Well, within the past few days I noticed the bias was not holding and I had to keep adjusting it upward until I ran out of adjustment rotation on one of the pots. I figured that's not good so I pulled it and put a WZ68 back in. With the WZ68 bias on all four output tubes is holding at 0.55 again and doing so with less turns on the adjustment pots. I gotta assume the 5R4GYS won't make the cut in this amp???

    deepee99

    Posts : 1260
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: That Good Old Rectifier Sound

    Post by deepee99 on Fri Nov 28, 2014 6:00 pm

    wgallupe wrote:UPDATE: Earlier in this thread I had mentioned that the Philips 5R4GYS was working OK for almost a month in my ST120. Well, within the past few days I noticed the bias was not holding and I had to keep adjusting it upward until I ran out of adjustment rotation on one of the pots. I figured that's not good so I pulled it and put a WZ68 back in. With the WZ68 bias on all four output tubes is holding at 0.55 again and doing so with less turns on the adjustment pots. I gotta assume the 5R4GYS won't make the cut in this amp???

    I had similar experiences with the 5R4GYS's in my M-125s. They sure look pretty, but don't quite make the cut. Also had a reject rate of about 10 percent out of the box.

    sKiZo

    Posts : 1287
    Join date : 2013-04-01
    Location : Michigan USA

    Re: That Good Old Rectifier Sound

    Post by sKiZo on Fri Nov 28, 2014 6:27 pm

    Just to refresh the memory ... yup, same thing here. So that makes at least three of us.

    Eh ... don't know till ya tries I guess. It's like sticking your tongue in a light socket.

    OW

    We learn from our

    OW

    mistakes.

    OW

    Most of us

    OW

    Eventually anyway

    .
    .
    .
    .
    .

    OW

    deepee99

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    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: That Good Old Rectifier Sound

    Post by deepee99 on Fri Nov 28, 2014 6:33 pm

    Guess that's why Kevin had such a "Deal" on them.
    Assuming the pin-out's the same, they might be ok in an ST-70.

    wgallupe

    Posts : 81
    Join date : 2014-05-18
    Age : 62
    Location : Central Mass.

    Re: That Good Old Rectifier Sound

    Post by wgallupe on Fri Nov 28, 2014 8:24 pm

    After reading all the info about it on Upscale's website, I bought two thinking I would have a backup and be all set for a few years! I'm hoping I can return the unused one Rolling Eyes

    Gregg R.

    Posts : 80
    Join date : 2014-02-20
    Age : 71
    Location : Land of 11,842 Lakes

    Tube Rectifier sound

    Post by Gregg R. on Fri Nov 28, 2014 8:42 pm

    Thanks for all the good info on the Phillips 5R4GYS!!
    I almost pulled the trigger on this tube from Kevin Deal/Upscale Audio a few months ago! It makes  me question Deal's business practices as far as NOS glass. Maybe he deletes negative reviews of stuff he's trying to move out!!

    I think I will stick with the Weber WZ-68; no problems whatsoever after nearly nine months and several  tube changes.

    wgallupe

    Posts : 81
    Join date : 2014-05-18
    Age : 62
    Location : Central Mass.

    Re: That Good Old Rectifier Sound

    Post by wgallupe on Fri Nov 28, 2014 9:33 pm

    I don't think its fair to blame Kevin Deal or question his business practices. Its not his fault that the ST120 puts too much demand on most GZ34 rectifiers.

    frank

    Posts : 95
    Join date : 2011-02-14
    Location : Pacific Northwest

    Re: That Good Old Rectifier Sound

    Post by frank on Fri Nov 28, 2014 9:59 pm

    I've bought tubes from Upscale Audio. They really promoted them as being the best thing since sliced bread... And... I'm happy with them, they really are great! http://www.upscaleaudio.com/cifte-12au7/

    I paid a lot less then, though.


    Last edited by frank on Sat Nov 29, 2014 1:00 am; edited 2 times in total (Reason for editing : left out a space)

    sKiZo

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    Join date : 2013-04-01
    Location : Michigan USA

    Re: That Good Old Rectifier Sound

    Post by sKiZo on Sat Nov 29, 2014 2:25 am

    wgallupe wrote:I don't think its fair to blame Kevin Deal or question his business practices. Its not his fault that the ST120 puts too much demand on most GZ34 rectifiers.

    Yah but ... Upscale does list them as "The best buy and best made 5AR4/5U4G/GZ33/GZ37".

    Neither a GZ33 or GZ37 has any problem installed in an ST120 ...

    I just dropped a note to Upscale:

    Just so you're aware of issues using the Phillips 5R4GYS in the Latino ST120 and ST150 amps, I know of three early failures (including mine), using the Phillips tube. They'll bias up fine out of the box, but get progressively weaker, and fast, to the point where they won't provide adequate power.

    You may wish to correct your website to reflect that it is NOT a good substitute for a GZ33 or GZ37 rectifier, at least for the larger Latino amps, any of which work fine with the GZ33 or GZ37 tubes.


    Somebody else mentioned the published reviews on the site ... looks like 5 stars all the way!  sunny

    frank

    Posts : 95
    Join date : 2011-02-14
    Location : Pacific Northwest

    Re: That Good Old Rectifier Sound

    Post by frank on Sat Nov 29, 2014 3:27 am

    sKiZo wrote:
    wgallupe wrote:I don't think its fair to blame Kevin Deal or question his business practices. Its not his fault that the ST120 puts too much demand on most GZ34 rectifiers.

    Yah but ... Upscale does list them as "The best buy and best made 5AR4/5U4G/GZ33/GZ37".

    Neither a GZ33 or GZ37 has any problem installed in an ST120 ...

    I just dropped a note to Upscale:

    Just so you're aware of issues using the Phillips 5R4GYS in the Latino ST120 and ST150 amps, I know of three early failures (including mine), using the Phillips tube. They'll bias up fine out of the box, but get progressively weaker, and fast, to the point where they won't provide adequate power.

    You may wish to correct your website to reflect that it is NOT a good substitute for a GZ33 or GZ37 rectifier, at least for the larger Latino amps, any of which work fine with the GZ33 or GZ37 tubes.


    Somebody else mentioned the published reviews on the site ... looks like 5 stars all the way!  sunny

    Thanks for lookin' out for the peep's, Skiz! You definitely did your part.

    mazeeff

    Posts : 116
    Join date : 2014-01-06
    Age : 61
    Location : Grand Rapids, Michigan, USA

    Re: That Good Old Rectifier Sound

    Post by mazeeff on Sat Nov 29, 2014 5:55 am

    Given the large number of posts on rectifier failures, and potential musical impact, why would anyone run a tube rectifier. A SS rectifier is cheap, durable, and matches the amps used in the sixties. The mid 60's Marshalls, HiWatts, etc, were mostly SS rectification. I run SS rectification in my ST-70, and it is the most reliable part of the amp! If you miss the glow of the tube rectifier, just hook up the filament, and throw a couple of diodes inside the amp!

    Mike

    wgallupe

    Posts : 81
    Join date : 2014-05-18
    Age : 62
    Location : Central Mass.

    Re: That Good Old Rectifier Sound

    Post by wgallupe on Sat Nov 29, 2014 8:51 am

    sKiZo wrote:
    wgallupe wrote:I don't think its fair to blame Kevin Deal or question his business practices. Its not his fault that the ST120 puts too much demand on most GZ34 rectifiers.

    Yah but ... Upscale does list them as "The best buy and best made 5AR4/5U4G/GZ33/GZ37".


    Yes, I drank this 'cool aid' and bought into all of their hype about the tube. Now I realize they are over stating things a bit. That will be the basis of my argument for returning the unused one. Now that I think of it, I should also ask for warranty coverage on the one that's going bad.

    deepee99

    Posts : 1260
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: That Good Old Rectifier Sound

    Post by deepee99 on Sat Nov 29, 2014 2:58 pm

    Skiz, good for you. Be interesting to see if Kevin reproduces it.
    I remember, on another thread, Bob L. saying the 5R4GYS could maybe sorta work, but can't keep up with the Dynaco voltage swings demanded. And the out-of-the-box failure rate and gradual bias problems aren't the best.
    Wonder if they'd be OK for an ST-70, though. If somebody wants to guinea-pig I have four still in the unopened shipping box they can have for $25 plus postage. PM if interested.
    This is no slam on Kevin but I've learned to do my own tube research rather than just buying into his hype. I have a 6-year-old Ah! Tjoeb CD player from him that has performed daily and flawlessly. As for plain tubes, though, IMHO there are better sources.

    Bob Latino
    Admin

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

    Re: That Good Old Rectifier Sound

    Post by Bob Latino on Sat Nov 29, 2014 5:29 pm

    Hi,

     The 5R4GYS might be OK for the VTA ST-70 or a stock ST-70 but you need "heavier artillery" (Weber WZ68, GZ33 or GZ37) for the VTA ST-120 or M-125 monoblocks. Now - A 5AR4 will work OK in the ST-120 and the M-125's but a 5AR4 will be operated right at the limits of its ability to provide current for these two amps. If your room is small, your speakers are fairly sensitive (maybe 93 dB or higher efficiency) and you don't play rock music at really high volume levels, you can get by with a 5AR4 in the ST-120 or M-125. A Weber WZ68, though, is inexpensive @ $22 a pop and the Weber will provide more current (450 milliamps) than the ST-120 or the M-125's will every use.

    Bob

    Gregg R.

    Posts : 80
    Join date : 2014-02-20
    Age : 71
    Location : Land of 11,842 Lakes

    Re: That Good Old Rectifier Sound

    Post by Gregg R. on Sun Nov 30, 2014 1:58 am

    There are 31 reviews of the Phillips 5R4GYS on the Kevin Deal/Upscale Audio website. 27 reviews give this rectifier tube a five-star rating. Yet there are at least three dissatisfied owners alone on this Dynaco website.  Unfortunately, the failures seem to occur after the 30 day warranty period.

    I hope Kevin Deal takes notice of sKiZo's comments!! I won't hold my breath, however!!


    Note: I turn 70 years old today! The older I get, the grumpier I get!


    Last edited by Gregg R. on Sun Nov 30, 2014 2:05 am; edited 1 time in total (Reason for editing : Grumpiness!!)

    sKiZo

    Posts : 1287
    Join date : 2013-04-01
    Location : Michigan USA

    Re: That Good Old Rectifier Sound

    Post by sKiZo on Sun Nov 30, 2014 2:09 pm

    You get my vote for Surly Curmudgeon of the day!



    You want it on a t-shirt, you'll have to print it yourself!  (mutter mumble grouse)

    PS ... happy birthday! And several more to come! What a Face

    Gregg R.

    Posts : 80
    Join date : 2014-02-20
    Age : 71
    Location : Land of 11,842 Lakes

    That Good Old Rectifier Sound

    Post by Gregg R. on Sun Nov 30, 2014 6:45 pm

    Thanks for all the Birthday wishes!!

    After a good night's sleep (9 hrs) and a terrific BM, I'm back to my usual cheerful self!!

    As far as the Phillips 5R4GYS rectifier tube, it's probably just not a good choice for VTA amps.

    Thanks,

    Gregg R.

    sKiZo

    Posts : 1287
    Join date : 2013-04-01
    Location : Michigan USA

    Re: That Good Old Rectifier Sound

    Post by sKiZo on Mon Dec 01, 2014 5:18 pm

    UPDATE on the 5R4GYS failures ...

    I did get a note back that this was the first they'd heard of a problem with the Latino amps ...

    PS ... Is it my imagination, or has any and all reference to the GZ33/GZ37 disappeared from this page?

    http://www.upscaleaudio.com/philips-5r4gys-made-in-holland/

    I'd still like to see an "exception" list as a substitute for the 5AR4 for certain equipment we all know and love. But ... baby steps ... baby steps ...

    I also updated THIS THREAD with a warning to all ...

    ... and a happy holiday BM to all!! clown

    deepee99

    Posts : 1260
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: That Good Old Rectifier Sound

    Post by deepee99 on Mon Dec 01, 2014 6:20 pm

    sKiZo wrote:UPDATE on the 5R4GYS failures ...

    I did get a note back that this was the first they'd heard of a problem with the Latino amps ...

    PS ... Is it my imagination, or has any and all reference to the GZ33/GZ37 disappeared from this page?

    http://www.upscaleaudio.com/philips-5r4gys-made-in-holland/

    I'd still like to see an "exception" list as a substitute for the 5AR4 for certain equipment we all know and love. But ... baby steps ... baby steps ...

    I also updated THIS THREAD with a warning to all ...

    ... and a happy holiday BM to all!! clown

    Um, not exactly, Skiz. He lists $100 Mullard GZ-33s (a good price) but they're out of stock. But read down a little bit: "Attention! Before buying any 5AR4, 5U4, GZ33, or GZ37, here is a hot ticket from Uncle Kevy: Buy the Philips 5R4GYS made in Holland."
    And happy BMs to everyone, as well.

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