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    Tube rolling and the physical effects

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    tubenutr

    Posts : 62
    Join date : 2015-01-25
    Age : 59
    Location : Northern Ontario

    Tube rolling and the physical effects

    Post by tubenutr on Mon Mar 21, 2016 10:58 pm

    Good evening fellow travellers.

    I've had numerous moments of enlightenment this past week or so.

    Last week, I replaced the 6CA7s in my VTA ST70 with 6L6GCs. They had been broken in by the
    fellow I purchased them from. Well I wish I had one of Gizmo's diapers.
    Nice, nice, freaking awesome.
    This evening, I replaced the center 12au7 with a 12bh7..................another Gizmo
    moment.

    Bloody hell, I wish I had been here 25 yrs ago and not fooled with those evil sistors.


    M


    Last edited by Eskimo on Tue Mar 22, 2016 12:44 pm; edited 1 time in total

    bluemeanies

    Posts : 129
    Join date : 2015-02-09
    Age : 66
    Location : Folsom Pa.

    Re: Tube rolling and the physical effects

    Post by bluemeanies on Tue Mar 22, 2016 7:54 am

    Hello Ontario,
    Was this a measured test or a listening experience or maybe an epiphany?
    Not being flip here. In my personal experience I believe in what I hear more than what I see on segment displays involving the subject of tubes/valves.
    I have the Bob Latino m125 mono-blocks and could not be happier.
    I finally was bought into the light of quality 2channel listening that I thought I could never afford to own. Owning tubes amplifiers were not an issue, but to own QUALITY tube amplifiers at reasonable prices and important to me made in the USA was a journey.
    I have standard tubes in the m125's and they to an excellent job so my question is do you feel the upgrade was worth it by a listening point of view?
    Just how more efficient is your ST70.

    Thanks

    tubenutr

    Posts : 62
    Join date : 2015-01-25
    Age : 59
    Location : Northern Ontario

    Re: Tube rolling and the physical effects

    Post by tubenutr on Tue Mar 22, 2016 12:46 pm

    bluemeanies,

    This was definitely a listening test.

    The upgrade was very much worth it.

    sKiZo

    Posts : 1313
    Join date : 2013-04-01
    Location : Michigan USA

    Re: Tube rolling and the physical effects

    Post by sKiZo on Sat Mar 26, 2016 7:50 pm

    Happy accidents sometimes ...

    I've had a nicely matched set of Sylvania 12BH7's for some time now that I've always used in the side channels. Had one go noisy, so figured what da hey, eh ... slap the good one in the center. That's been there for quite some time now, driving a set of 5963's in the channel positions on my ST120 ... very tasty combo!

    Then again, the tubes you have real high hopes for can sometimes result in epic fails. Spent top dollar for a nicely matched set of Tele 12AU7's ... sonically "correct" in every way, but there's something missing IMHO.

    eickmewg

    Posts : 43
    Join date : 2014-08-29

    Re: Tube rolling and the physical effects

    Post by eickmewg on Sat Mar 26, 2016 8:11 pm

    I've settled on 12BH7's in all three driver board positions along with KT120 power tubes in my ST120. I currently have new production EH 12BH7's in the amp and they sound good to me and are nice and quiet.

    tubenutr

    Posts : 62
    Join date : 2015-01-25
    Age : 59
    Location : Northern Ontario

    e: Tube rolling and the physical effects

    Post by tubenutr on Sat Mar 26, 2016 11:07 pm

    I have been stung so many times by NIB/NOS tubes that I've almost given up on them and just buy new prod tubes.
    They are not that bad and if you find a good vendor (the tube store) you can be assured of quality product.

    deepee99

    Posts : 1337
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: Tube rolling and the physical effects

    Post by deepee99 on Sun Apr 03, 2016 7:36 am

    Eskimo, Skiz et. al, some years ago I was seated on a long flight next to a lens-grinder who worked for Nikkor (Nikon's lens maker). He said that the only real difference in quality between the very expensive Nikkor lenses and the el-cheapo Vivitars of the time was a matter of luck. You could get a great lens or a crappy one from either maker, regardless of price or specs. Just depended on the day, who was doing the work, and what kind of glass they had at that moment.
    I found that a very interesting confession from one of the honchos of reputedly the finest lens-makers on the planet. One might apply this to tubes as well. You might get lucky with some counterfeit knock-off that will serve you well for 10k hours, and be burned by a hyper-expensive original-in-the-box 1940's beauty that gives up the ghost after 50 hours.
    Tubes, like camera lenses, are a crap-shoot. Win a few, lose a few.

    peterh

    Posts : 681
    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: Tube rolling and the physical effects

    Post by peterh on Sun Apr 03, 2016 8:43 am

    deepee99 wrote:Eskimo, Skiz et. al, some years ago I was seated on a long flight next to a lens-grinder who worked for Nikkor (Nikon's lens maker). He said that the only real difference in quality between the very expensive Nikkor lenses and the el-cheapo Vivitars of the time was a matter of luck. You could get a great lens or a crappy one from either maker, regardless of price or specs. Just depended on the day, who was doing the work, and what kind of glass they had at that moment.
    I found that a very interesting confession from one of the honchos of reputedly the finest lens-makers on the planet. One might apply this to tubes as well. You might get lucky with some counterfeit knock-off that will serve you well for 10k hours, and be burned by a hyper-expensive original-in-the-box 1940's beauty that gives up the ghost after 50 hours.
    Tubes, like camera lenses, are a crap-shoot. Win a few, lose a few.

    Interesting,  but i would not put nikon in another class then vivitar. If any japanese
    lenses are top notch it is pentax.
    Talk about REAL lenses ( kern, leitz zeiss etc )is another issue, here my impression is that
    luck has less presence.

    As for tubes however there is a point, the spread is so huge that a good specimen
    from a cheap maker could be better then a bad specimen from a top notch maker.
    It's an issue of mechanical parts made and assembled by humans, and by small
    distances that make a huge difference.
    Looking a NOS tubes ( as they used to be ) the same applies there. Tubes are
    dissimular. People at the time know this and had the ability to create amps that
    did not rely on specific tube parameters.

    Kentley

    Posts : 335
    Join date : 2015-03-06
    Age : 64
    Location : Worcester, MA

    Re: Tube rolling and the physical effects

    Post by Kentley on Sun Apr 03, 2016 9:02 am

    Great discussion.
    So, for us at the end of the chain, there is an approach which may bring us closer to consistency. That is to purchase our tubes, whether new-manufacture, "NOS", used, etc. from a reputable dealer who has the equipment and experience to cull the herd for the best of the best.
    No one is perfect, but in my limited experience there are two sellers who stand out. Jim McShane for the new tubes and Andy Bowman for the old ones. These guys are great. Anyone else you care to mention whose service and product has been exemplary?
    And yes - I have bought from others (EeeBay etc.) and I've gotten some great products and deals, but...some dingers as well.

    deepee99

    Posts : 1337
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: Tube rolling and the physical effects

    Post by deepee99 on Sun Apr 03, 2016 9:21 am

    Kentley, I must concur. Andy for the old farts, Jim for the new Russkies.
    Seems to me that the NOS market has become a racket; it's a coin toss.
    James and Andy back their products and will make you whole if one goes pear-shaped.
    Methinks that peterh has a very good point: get an amp or preamp that is not dependant on published tube behaviours and can wrap itself around different modalities. Which is why we're here.

    Tube Nube

    Posts : 643
    Join date : 2008-12-06
    Age : 53
    Location : Calgary, AB

    Re: Tube rolling and the physical effects

    Post by Tube Nube on Sun Apr 03, 2016 7:53 pm

    I need to echo Peter's protest about lenses. I think Deepee's acquaintance inadvertently confessed that comtrary to reputation, Nikon does not tower over it's Japanese competitors when it comes to optics.

    I promise you, though, that Leica lenses are in a different league.

    Last year I bought a "new" camera--an M3 with a Summicron 50 F2 lens, both looking near new--manufactured in '57 or '58! There are 50mm lenses for 35mm cameras that render differently, of course, but none that are "superior", some argue.

    I think the same viewpoint has often been offered for some of the great nos tubes. Sylvania, for e,g,?

    But take me with a grain of salt, I also claim to have improved my daily shave by going to a straight "cut throat" razor. (Youve gotta check out Hart Steel if you have any interest in those!)

    GP49

    Posts : 735
    Join date : 2009-04-30
    Location : East of the sun and west of the moon

    Re: Tube rolling and the physical effects

    Post by GP49 on Mon Apr 04, 2016 2:28 pm

    Interestingly, the only "normal" lens I have used that matches the Leitz Summicron on my M3 is the SMC Pentax on my LX...and it's an older-generation Pentax lens, bigger than the one in production when the LX was made.

    Tube Nube

    Posts : 643
    Join date : 2008-12-06
    Age : 53
    Location : Calgary, AB

    Re: Tube rolling and the physical effects

    Post by Tube Nube on Mon Apr 04, 2016 2:52 pm

    Another M3 fan! I subsequently got a R4, but now think I don't like SLR's any more. At least at the moment.

    Pentax LX: http://www.mir.com.my/rb/photography/hardwares/classics/pentaxlx/

    Looks like an exceptional camera, then and, I'm sure, now still.

    deepee99

    Posts : 1337
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: Tube rolling and the physical effects

    Post by deepee99 on Mon Apr 04, 2016 4:56 pm

    You'll pry my Nikon F2 and its lenses from my cold dead fingers.
    Anyway, back to tubes. Anyone blow something interesting up recently?

    10-E-C

    Posts : 87
    Join date : 2014-02-12
    Age : 63
    Location : upper east tn

    Re: Tube rolling and the physical effects

    Post by 10-E-C on Mon Apr 04, 2016 8:02 pm

    deepee99 wrote:You'll pry my Nikon F2 and its lenses from my cold dead fingers.
    Anyway, back to tubes. Anyone blow something interesting up recently?




    I didn't blow anything up, just had a 12bh7 bite the dust.

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