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    Gold Lion KT-88 tube longevity, thanks Jim McShane

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    deepee99

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

    Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by deepee99 on Thu Apr 21, 2016 12:49 pm

    Other than one out-of-the-box failure, I've had only one GL KT-88 go ka-blooey, and that was yesterday. Loud pop, and it took out the fuse. In ordering a replacement octet for the Big Boppers from my go-to Russian tube guy, Jim McShane, he looked up his purchase records and we calculated that that tube gave up the ghost north of 5,000 hours. (Its brethren are still huffing and puffing just fine but likely headed for the same cliff, so out they all go).
    An 8-pack of GL-KT-88s costs about $450. That works out to just under 10 cents/hour for a full rack of output tubes for an M-125-type listening pleasure.
    I don't exactly molly-coddle my tubes, but I keep the bias in the .5-.55 range. No point I can see in running them up to .6 or higher. The amps stay in Class A and I think Gold Lion has made the penny drop in terms of sound quality. No doubt MontanaWay's fiddling with the the capacitors has helped, too, along with the delayed start relay Bob/Roy designed.
    So for less than $1 a day, all day long, you get the finest sound imaginable. That's less than a single can of Rainier beer, as Longmire would say.



    Tube Nube

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

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by Tube Nube on Thu Apr 21, 2016 7:45 pm

    Ugh! Why would you sully those sweet soul sounds with Raineer, or even the mere mention of it.

    BNR_1

    Posts : 78
    Join date : 2013-06-11

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by BNR_1 on Thu Apr 21, 2016 10:56 pm

    I was wondering, separate of sonic qualities, would the KT-120s perform longer the then KT88s?

    Out of curiosity, how long did it take you to rack up 5,000 hrs? I can tell you if it was me it would probably be 6 to 7 years at the rate I listen to my system.

    Thanks

    deepee99

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

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by deepee99 on Fri Apr 22, 2016 4:28 pm

    BNR_1 wrote:I was wondering, separate of sonic qualities, would the KT-120s perform longer the then KT88s?

    Out of curiosity, how long did it take you to rack up 5,000 hrs?  I can tell you if it was me it would probably be 6 to 7 years at the rate I listen to my system.

    Thanks

    Hi, BNR,
    I would think mathematically that the KT-120s and KT-150s with their larger plates should last longer, but there are so many other variables, among them metallurgy, the quality of the vacuum seal, the QC & etc., where they were made, etc., etc. According to Jim McShane's records, I bought those tubes in late 2012, so 3.5 years to wear one out, I guess. I'm a bit anal this way; if one fails in the rack I pull all four out and replace with a new quartet.
    I keep the amps lit pretty much all day long. Morning jazz, afternoon rock, evening television. I do remember to turn them off at night, but they're probably pulling 12-14 hours per day at varying rates of input from the preamp.
    The KT-120s (at least the ones I had) gassed-up pretty quickly; that shiny getter flashing went grey in a few hundred hours. The GL KT-88s hold their vacuum much longer.
    I went through much experimentation with bias settings and found that .5 to .55/tube is plenty. Makes life easier on the tube and unless you're trying to overpower an Allison or Pratt & Whitney light up next door will fill the room just fine.
    Bob Latino recommends .6/tube(1.2 the pair) but I think that is not necessary. Go for around <.55/tube and you and your tubes will be happy.




    corndog71

    Posts : 454
    Join date : 2013-03-19
    Location : It can get windy here

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by corndog71 on Fri Apr 22, 2016 5:08 pm

    For longer life keep the bias low. KT88 - 0.40vdc.

    Guest
    Guest

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by Guest on Fri Apr 22, 2016 5:43 pm

    with my builds using KT120's I am VERY conservative, I set them at 500mV before I ship them out!
    Unless a client requests otherwise, I found that 500mV is more than enough, and frankly, I really cannot hear that much difference between 500mV and say 600mV!
    But then, sound is so subjective anyway! Wink

    BNR_1

    Posts : 78
    Join date : 2013-06-11

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by BNR_1 on Fri Apr 22, 2016 6:34 pm

    Good info. Thanks all for responding.

    Deep I have never listened to my TV with my tube amps. Got to give that a try one day. Problem is that my TV uses aerial and in my neck of the woods, I catch practically no channels. This is what led me into listening more music. Before moving here my listening was close to zero. In hindsight, catching very little channels is a blessing. I focus more on soft listening and catching up on reading.

    deepee99

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

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by deepee99 on Fri Apr 22, 2016 6:46 pm

    BNR_1 wrote:Good info.  Thanks all for responding.

    Deep I have never listened to my TV with my tube amps.  Got to give that a try one day.  Problem is that my TV uses aerial and in my neck of the woods, I catch practically no channels.  This is what led me into listening more music.  Before moving here my listening was close to zero.  In hindsight, catching very little channels is a blessing.  I focus more on soft listening and catching up on reading.
    Ditto here, unless you want to pay $100/month for satellite. We got a Roku box for $80 and maybe watch a Netflix series or movie nightly for $8 a month. Some movies sound astoundingly good on the toobs. I have found that without network TV and its news channels my blood pressure has dropped by a third. The lack of spending money on blood pressure meds more than compensates for the cost of tubes every three or four years.

    Guest
    Guest

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by Guest on Fri Apr 22, 2016 6:51 pm

    deepee99 wrote:
    BNR_1 wrote:Good info.  Thanks all for responding.

    Deep I have never listened to my TV with my tube amps.  Got to give that a try one day.  Problem is that my TV uses aerial and in my neck of the woods, I catch practically no channels.  This is what led me into listening more music.  Before moving here my listening was close to zero.  In hindsight, catching very little channels is a blessing.  I focus more on soft listening and catching up on reading.
    Ditto here, unless you want to pay $100/month for satellite. We got a Roku box for $80 and maybe watch a Netflix series or movie nightly for $8 a month. Some movies sound astoundingly good on the toobs. I have found that without network TV and its news channels my blood pressure has dropped by a third. The lack of spending money on blood pressure meds more than compensates for the cost of tubes every three or four years.

    not to mention more Rainier's!......... Razz

    deepee99

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

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by deepee99 on Fri Apr 22, 2016 8:25 pm

    Quit picking on God's beer!!! Or I'll send Sheriff Longmire after ye.

    j beede

    Posts : 328
    Join date : 2011-02-07
    Location : California

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by j beede on Fri Apr 22, 2016 10:50 pm

    deepee99 wrote:Other than one out-of-the-box failure, I've had only one GL KT-88 go ka-blooey, and that was yesterday. Loud pop, and it took out the fuse. In ordering a replacement octet for the Big Boppers from my go-to Russian tube guy, Jim McShane, he looked up his purchase records and we calculated that that tube gave up the ghost north of 5,000 hours. (Its brethren are still huffing and puffing just fine but likely headed for the same cliff, so out they all go).
    An 8-pack of GL-KT-88s costs about $450. That works out to just under 10 cents/hour for a full rack of output tubes for an M-125-type listening pleasure.
    I don't exactly molly-coddle my tubes, but I keep the bias in the .5-.55 range. No point I can see in running them up to .6 or higher. The amps stay in Class A and I think Gold Lion has made the penny drop in terms of sound quality. No doubt MontanaWay's fiddling with the the capacitors has helped, too, along with the delayed start relay Bob/Roy designed.
    So for less than $1 a day, all day long, you get the finest sound imaginable. That's less than a single can of Rainier beer, as Longmire would say.



    Out they go... Are you going to post your leftover Gold Lion KT-88s? I'd buy them from you.

    deepee99

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

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by deepee99 on Sat Apr 23, 2016 10:28 am

    PM me and we can certainly talk. I've got a half-dozen or so I could let go of. Won't vouch for any of them as they've all had some time put on them. Just check 'em for shorts and I'm sure they'll go a long time. Lots of getter flashing left on them.

    audiobill

    Posts : 270
    Join date : 2014-03-13
    Location : Philadelphia

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by audiobill on Wed May 04, 2016 4:00 pm

    I've been listening to the Sovtek 6550s recently, and can report that they are well made and sound great in the VTA amps. With supplies of kt88s drying up, good to know!

    deepee99

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

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by deepee99 on Thu May 05, 2016 10:59 am

    audiobill wrote:I've been listening to the Sovtek 6550s recently, and can report that they are well made and sound great in the VTA amps. With supplies of kt88s drying up, good to know!

    Audio Bill,
    I see there are several iterations of the Sovtek 6550s, the WEs being the most prevalent. Is that what you're using?

    Bob Latino
    Admin

    Posts : 2415
    Join date : 2008-11-26
    Location : Massachusetts

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by Bob Latino on Thu May 05, 2016 12:47 pm

    audiobill wrote:I've been listening to the Sovtek 6550s recently, and can report that they are well made and sound great in the VTA amps. With supplies of kt88s drying up, good to know!

    Sovtek has stopped making KT88 output tubes. The Sovtek KT88's were reasonably priced Russian made output tubes that sounded very good. Last month I bought a quad of the Sovtek 6550WE output tubes and listened to them extensively for about a week off and on and compared them to a quad of Sovtek KT88's that I also had here. The 6550WE's are physically larger than a KT88 and appear to be very durable. The sound quality between these two tubes is virtually the same with the 6550's leaning just a little bit towards the "tubey" side of a musical presentation as compared to the KT88. The internal physical construction of both tubes is very similar also. (see photo) I then purchased another matched quad and used the two quads in my two VTA M-125 monoblocks. Same presentation as in the ST-120 with even better soundstaging in the M-125's ..

    Bob

    Sovtek 6550 on the left and Sovtek KT88 on the right ...



    deepee99

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

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by deepee99 on Thu May 05, 2016 1:02 pm

    Sovteks on the left of me, Sovteks on the right, here I am stuck in the middle with you (with apologies to Stealer's Wheel).
    Sorry Bob, couldn't resist.

    audiobill

    Posts : 270
    Join date : 2014-03-13
    Location : Philadelphia

    Re: Gold Lion KT-88 tube longevity, thanks Jim McShane

    Post by audiobill on Thu May 05, 2016 4:15 pm

    David, you should really match the tube types on the left and right.....channels.

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