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    My VERY first tube amp.

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    deepee99

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

    Re: My VERY first tube amp.

    Post by deepee99 on Fri Aug 29, 2014 4:00 pm

    MontanaWay wrote:
    deepee99 wrote:
    MontanaWay wrote:I know a lot of people prefer the look of glass and the glow....but it is near impossible to improve upon a Weber Copper TopWZ34 or WZ68....those things are 88mm flak proof!!!!!!!!

    I live with the copper-caps, too, but Holger I gotta tell ya when you light up a pair of Mullard GZ-33s in the middle of winter, the house lights go dim and the dog gets out of your lap 'cuz he doesn't need the heat anymore and the bass plumps up just ever so nice. Just don't ever blow one up; they're about $150 to replace.

    oh no doubt!....but at that cost....looking pretty aint worth that much!!! Shocked

    You've never been to a Bangkok pole-dancing hangout, have you?

    Guest
    Guest

    Re: My VERY first tube amp.

    Post by Guest on Fri Aug 29, 2014 4:12 pm

    deepee99 wrote:
    MontanaWay wrote:
    deepee99 wrote:
    MontanaWay wrote:I know a lot of people prefer the look of glass and the glow....but it is near impossible to improve upon a Weber Copper TopWZ34 or WZ68....those things are 88mm flak proof!!!!!!!!

    I live with the copper-caps, too, but Holger I gotta tell ya when you light up a pair of Mullard GZ-33s in the middle of winter, the house lights go dim and the dog gets out of your lap 'cuz he doesn't need the heat anymore and the bass plumps up just ever so nice. Just don't ever blow one up; they're about $150 to replace.

    oh no doubt!....but at that cost....looking pretty aint worth that much!!! Shocked

    You've never been to a Bangkok pole-dancing hangout, have you?

    yes, I've been to Patpong Road!......... What a Face

    Jim McShane

    Posts : 154
    Join date : 2011-10-19
    Location : South Suburban Chicago

    Re: My VERY first tube amp.

    Post by Jim McShane on Fri Aug 29, 2014 5:35 pm

    deepee99 wrote:
    Jim McShane wrote:"Keep an eye out for an old Mullard GZ34 - same ratings, but much more robust than today's production."


    I'm not so sure that's true - or as true as it once was. The new production Genalex and Tung-Sol have been bulletprof. Only time will tell, but IMHO you don't have to pay for old stock anymore to get a high quality and durable rectifier tube.

    Jim, anyone making a decent GZ-33 anymore? I hate the cost of those NOS Mullards.

    No one I know of, sorry to say...

    deepee99

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

    Re: My VERY first tube amp.

    Post by deepee99 on Fri Aug 29, 2014 6:53 pm

    Jim McShane wrote:
    deepee99 wrote:
    Jim McShane wrote:"Keep an eye out for an old Mullard GZ34 - same ratings, but much more robust than today's production."


    I'm not so sure that's true - or as true as it once was. The new production Genalex and Tung-Sol have been bulletprof. Only time will tell, but IMHO you don't have to pay for old stock anymore to get a high quality and durable rectifier tube.

    Jim, anyone making a decent GZ-33 anymore? I hate the cost of those NOS Mullards.

    No one I know of, sorry to say...

    Jim, would the -34s you mention pull enough mud for an M-125 with KT-120s?

    corndog71

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

    Re: My VERY first tube amp.

    Post by corndog71 on Fri Aug 29, 2014 6:58 pm

    I have no regrets making my VTA ST120 with solid state rectifiers.  I've lost too many 5AR4 tubes to my old ST70 and MkIV's.  I put 2 diodes in series per leg of the half-wave rectifier.  Have had no issues and since the amp runs through a variac at 117VAC the increased voltage is manageable.



    Last edited by corndog71 on Fri Aug 29, 2014 8:39 pm; edited 1 time in total

    Tevian

    Posts : 7
    Join date : 2014-08-17

    Re: My VERY first tube amp.

    Post by Tevian on Fri Aug 29, 2014 7:17 pm

    Interesting information about the tube rectifier. I'm currently running a JJ GZ34 tube. I've read around that its not a terrible choice. I did order the new HVT and will be replacing the old one soon. Switching to SS rectifier may be an option but for now I just like the look of it.

    deepee99

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

    Re: My VERY first tube amp.

    Post by deepee99 on Fri Aug 29, 2014 7:31 pm

    Tevian wrote:Interesting information about the tube rectifier. I'm currently running a JJ GZ34 tube. I've read around that its not a terrible choice. I did order the new HVT and will be replacing the old one soon. Switching to SS rectifier may be an option but for now I just like the look of it.  

    I'm with you there, Tevian. From my expensive experience, rectifier behaviour depends upon speaker load. If you can keep your speak load up above 3 or 4 ohms, with the output xformers tapped appropriately, you'll not hear a difference between the Webers and the much spendier, albeit sexier, tubes. When I was running Maggies and AMTs in series, which dropped the load down below 2 ohms, the Webers would last about a month between meltdowns but my GZ-33 Mullards could stand it.
    With newer speaks (which pull about 4 ohms nominal), no worries. I was blaming the Weber failures on line voltage and/or poor QC but the speaker load was the variable, at least in my case, and we get some pretty hot line voltages around here, up around 122.
    Tube amps are a lot fussier than sand amps but ya gets what ya pays for.
    To sKIZo, quit blowing your amps up. It's not polite. See you in Montana.

    Jim McShane

    Posts : 154
    Join date : 2011-10-19
    Location : South Suburban Chicago

    Re: My VERY first tube amp.

    Post by Jim McShane on Sat Aug 30, 2014 12:05 pm

    deepee99 wrote:
    Jim McShane wrote:
    deepee99 wrote:
    Jim McShane wrote:"Keep an eye out for an old Mullard GZ34 - same ratings, but much more robust than today's production."


    I'm not so sure that's true - or as true as it once was. The new production Genalex and Tung-Sol have been bulletprof. Only time will tell, but IMHO you don't have to pay for old stock anymore to get a high quality and durable rectifier tube.

    Jim, anyone making a decent GZ-33 anymore? I hate the cost of those NOS Mullards.

    No one I know of, sorry to say...

    Jim, would the -34s you mention pull enough mud for an M-125 with KT-120s?

    They are run so close to their limits I would not recommend them. You can use them with the diode mod, but a copper cap is likely the best bet. I believe Bob makes the same recommendation.

    deepee99

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

    Re: My VERY first tube amp.

    Post by deepee99 on Sat Aug 30, 2014 12:09 pm

    Jim, thanks.
    I've had no grief with the Webers since I got my speaker impedance issue resolved. I keep the GZ-33s for winter when the gas company shuts my furnace off or I want to impress visiting royalty.
    BTW, did you mean triode mode?

    Jim McShane

    Posts : 154
    Join date : 2011-10-19
    Location : South Suburban Chicago

    Re: My VERY first tube amp.

    Post by Jim McShane on Sat Aug 30, 2014 12:15 pm

    deepee99 wrote:Jim, thanks.
    I've had no grief with the Webers since I got my speaker impedance issue resolved. I keep the GZ-33s for winter when the gas company shuts my furnace off or I want to impress visiting royalty.
    BTW, did you mean triode mode?

    No, I meant the diode mod for the rectifier hookup. It's in the sticky threads.

    deepee99

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

    Re: My VERY first tube amp.

    Post by deepee99 on Sat Aug 30, 2014 12:22 pm

    Jim McShane wrote:
    deepee99 wrote:Jim, thanks.
    I've had no grief with the Webers since I got my speaker impedance issue resolved. I keep the GZ-33s for winter when the gas company shuts my furnace off or I want to impress visiting royalty.
    BTW, did you mean triode mode?

    No, I meant the diode mod for the rectifier hookup. It's in the sticky threads.

    Gotcha. Guess there's pros and cons on that topic. Think I'll try not to fix what ain't broken ... Thanks, Jim, you have been a huge help to me and the KT-88s and -120s I've bought from you over the years have never gone south.

    Thread drift here, but how are the guys at New Sensor doing?


    Jim McShane

    Posts : 154
    Join date : 2011-10-19
    Location : South Suburban Chicago

    Re: My VERY first tube amp.

    Post by Jim McShane on Sat Aug 30, 2014 1:53 pm

    So far so good I guess - they don't share a lot of business info. But there's been no supply interruptions I know of other than the occasional back order which can always occur.

    Thanks SO much for the kind words too!

    tubes4hifi
    Admin

    Posts : 1292
    Join date : 2008-11-30

    Re: My VERY first tube amp.

    Post by tubes4hifi on Tue Sep 02, 2014 12:36 am

    New Sensor?? I quit buying any tubes from them, their prices are higher than just about any body else out there!!
    Unless buying more than a hundred of any one item. Their quantity 10 prices are higher than almost anyone elses single tube prices.

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