Tung Sol Reissue 12AX7 not for CF stage !!!
Moderator: VelvetGeorge
-
- New Member
- Posts: 1
- Joined: Sat Oct 11, 2008 8:14 am
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
What is your cathode voltage? I'm thinking possibly they're failing from high cathode heater voltage rather than too much current - you'll find 12ax7 datasheets actually state max 200V heater to cathode. A good idea is to reference the centre tap of the filament supply to above ground - just voltage divide tap off B+.
-
- Senior Member
- Posts: 599
- Joined: Mon Dec 18, 2006 3:35 am
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
I agree that the Tung Sol 12ax7 reissue tubes sound great. But...I have had two which had a "hum" issue and I found out that this problem has not been uncommon with them.
Joe
Joe
- LivewireBlanco
- Senior Member
- Posts: 97
- Joined: Tue Dec 11, 2007 12:39 am
- Location: San Angelo, TX
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
Been running the Tung Sol RI in my V2 on my JTM45 and Marshall Vintage Modern for almost a year now and they still sound excellent. Did I just get a good batch or what???
"I play country the way a good rock guitarist should."
- HTH
- Senior Member
- Posts: 600
- Joined: Thu Nov 27, 2008 8:53 am
- Just the numbers in order: 7
- Location: Newcastle, UK
- Contact:
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
^ +1weasel wrote:What is your cathode voltage? I'm thinking possibly they're failing from high cathode heater voltage rather than too much current - you'll find 12ax7 datasheets actually state max 200V heater to cathode. A good idea is to reference the centre tap of the filament supply to above ground - just voltage divide tap off B+.
exactly what I was thinking when reading this thread too. referencing the heaters at around 50v will take the stress off the CF stage and makes the amp hum less too in my experience.
"If you can possibly manage the time, please play both sides at one meeting"
http://www.youtube.com/TeleCustom72" onclick="window.open(this.href);return false;
http://www.youtube.com/TeleCustom72" onclick="window.open(this.href);return false;
- Ricky Lee
- Senior Member
- Posts: 813
- Joined: Wed May 04, 2005 6:23 pm
- Just the numbers in order: 7
- Location: Iuka, Mississippi
- Contact:
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
I have Tung Sol 12AX7 in all sockets of my 68 12xxx which has an extra tube for the effects loop and they sound great. However, I did have one go bad very quickly in v2 which I replaced with another Tung Sol 12AX7 that has lasted for months now with no issues. Maybe this is limited to just a bad batch of tubes.
May the good Lord take a liking to you!
http://s623.photobucket.com/albums/tt31 ... i%2012xxx/" onclick="window.open(this.href);return false;
http://s623.photobucket.com/albums/tt31 ... i%2012xxx/" onclick="window.open(this.href);return false;
-
- New Member
- Posts: 28
- Joined: Tue Dec 09, 2008 12:11 am
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
How do the US made Tung-Sol compare to the re-issues?
- novosibir
- Senior Member
- Posts: 4654
- Joined: Tue Nov 22, 2005 2:32 pm
- Just the numbers in order: 7
- Location: Nuernberg, Germany
- Contact:
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
Like a Boéf Stroganoff to a Hot Dog.Beserkr wrote:How do the US made Tung-Sol compare to the re-issues?
Larry
The fault almost always is sitting in front of the amp
Larry's Website now with included Pix's Gallery
Larry's Website now with included Pix's Gallery
-
- New Member
- Posts: 28
- Joined: Tue Dec 09, 2008 12:11 am
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
Would they work well as a PI driver?novosibir wrote:Like a Boéf Stroganoff to a Hot Dog.Beserkr wrote:How do the US made Tung-Sol compare to the re-issues?
Larry
- novosibir
- Senior Member
- Posts: 4654
- Joined: Tue Nov 22, 2005 2:32 pm
- Just the numbers in order: 7
- Location: Nuernberg, Germany
- Contact:
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
What? The Hot Dog or the Boéf Stroganoff?
You aren't a friend of too many words, aren't you?
Larry
You aren't a friend of too many words, aren't you?
Larry
The fault almost always is sitting in front of the amp
Larry's Website now with included Pix's Gallery
Larry's Website now with included Pix's Gallery
-
- New Member
- Posts: 28
- Joined: Tue Dec 09, 2008 12:11 am
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
LOLnovosibir wrote:What? The Hot Dog or the Boéf Stroganoff?
You aren't a friend of too many words, aren't you?
Larry
Ok, you got me.. I would be wondering about the Boéf Stroganoff aka NOS Tung-Sol..
I keep the verbiage to a minimum, I don't want people to notice I haven't got a good grasp on the English language
- Rickey_Dee
- Senior Member
- Posts: 167
- Joined: Tue Nov 20, 2007 1:36 am
- Just the numbers in order: 7
- Location: Austria / Europe
- Contact:
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
had tung sol 12ax7's too, after about 1 year the tube in the cf stage died... so i'd recommend replacing them and saving them as a spare tube for V1 or whatever, as they could fail at any time, even after 1 year. anyway, i'm using nos miniwatts and telefunken in this amp now, but i only gig with the tung sol's and a gt 12ax7m in v2 that i had left, cause no one in the crowd will mention if there is nos glass in your amp.
Builds:
Metroamp 50W Lead Plexi
BYOC Tri-Boost
tbc...
Metroamp 50W Lead Plexi
BYOC Tri-Boost
tbc...
-
- New Member
- Posts: 23
- Joined: Fri Apr 24, 2009 10:55 am
- Just the numbers in order: 7
- Contact:
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
Most of the 12AX7 types out of Sarotov (Sovtek, Electro Harmonix, Tung Sol, New Sensor) cannot handle the high cathode voltages.
Some of the design spec sheets I have seen on these tubes says the heater to cathode limit is 100volts, which is well below the 12AX7/ECC83 design spec of 180 to 200v.
Supposedly the Sovtek 12AX7WC can, but I have no experience or data on this tube.
Some of the design spec sheets I have seen on these tubes says the heater to cathode limit is 100volts, which is well below the 12AX7/ECC83 design spec of 180 to 200v.
Supposedly the Sovtek 12AX7WC can, but I have no experience or data on this tube.
-
- Senior Member
- Posts: 5054
- Joined: Thu Apr 13, 2006 1:36 pm
- Just the numbers in order: 7
- Location: Drontheim. Norwegen
- Contact:
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
this topic has not received the attention it deserves as people put the TS "RI" in the cathode follower all the time. even amp manufactures does this, selling something that will only last for a few days.
my 45/100 has 360v on v2 BTW
my 45/100 has 360v on v2 BTW
http://www.myspace.com/20bonesband" onclick="window.open(this.href);return false;
http://www.myspace.com/prostitutes" onclick="window.open(this.href);return false;
Super 100 amps: 1202-119 & 1202-84
JTM45 RS OT JTM50 JMP50 1959/2203/34/39
http://www.myspace.com/prostitutes" onclick="window.open(this.href);return false;
Super 100 amps: 1202-119 & 1202-84
JTM45 RS OT JTM50 JMP50 1959/2203/34/39
- darkbluemurder
- Senior Member
- Posts: 484
- Joined: Fri Aug 04, 2006 8:07 pm
- Just the numbers in order: 7
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
The first two samples of the Tungsol RI sounded great. I then bought more, only to find out that they don't hold up in the phase inverter spot. I also found out that when used in amps where the first gain stage has a low value Rk the tube will cause the scratchy volume pot effect. By the average they are more microphonic than JJs or Chinese. Conclusion: I won't touch 'em again.
- Big Mike
- Senior Member
- Posts: 796
- Joined: Tue Oct 31, 2006 12:42 am
- Just the numbers in order: 7
- Location: East Bay California - Raider Nation
Re: Tung Sol Reissue 12AX7 not for CF stage !!!
I mostly use them in V1 of my cathode bias amps.
No issue (tung sol).
No issue (tung sol).
Metroamp kit JMP50 - CM OT
Metroamp JTM45 turned JMP50 w/Classictone OT
Marshall 2550 Jubilee
Powered by Thorn and Kauer guitars
Scumback Speakers
Metroamp JTM45 turned JMP50 w/Classictone OT
Marshall 2550 Jubilee
Powered by Thorn and Kauer guitars
Scumback Speakers