Mesa el34 str448

[bandit2013]

Being bigger bottles, would those fit in TC100?
I’m new to tube swapping, looking for a replacement set when the time comes. Thanks for all the info.

The TC100 can run 6L6GC tubes as it does have a bias switch, those are the big bottle tubes. Even the coke bottle STR420 or was that the STR430 will fit. Big bottle is just a reference for the glass diameter. EH 6CA7 tubes are big bottle, same diameter as a 6L6GC but runs on the EL34 bias. The Tung Sol EL34 B are almost the same diameter, just a bit smaller. I have run either of those in the TC100.

The only issue will be the tube ratings. If they are OK with 450VDC then you are good to go. I know that the Mesa STR450 is a no go with the 450VDC plate voltage. I found out the hard way with the TC-50. After that experiment, off to Petaluma for repair it when. Sure, blew out the fuse and the resultant transient took out the strobe mute circuit along with it. Nothing major got damaged. Tubes are still good so I can use them in the RA100.

If these tubes are the TAD EL34 B-STR, the data sheet from TAD's website looks ok for the TC or even the Badlander. If they are made by some other manufacturer, it becomes questionable.

https://www.tubeampdoctor.com/media/pdf/8e/57/8d/tad-datasheet_el34b-str_version1-3-01-12-17.pdf

 

[domct203]

I’m in agreement on these possibly being TAD EL34B. Here is a pic from the TAD website and other views from Reverb listings, compare yours paying attention to the mica spacers and plate structure:

Dom

 

[Mike Lamury]

I’m in agreement on these possibly being TAD EL34B. Here is a pic from the TAD website and other views from Reverb listings, compare yours paying attention to the mica spacers and plate structure:

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Dom

Yes these in the picture look the same as mine as far as every detail I compared. Thanks for yours and everyone else's help identifying these tubes. I'm recovering from foot and ankle surgery at the moment so as soon as I can stand up and get my amp down I'm going to put these EL34's in my Mark V!

 

[bandit2013]

So are these generally good tubes in your opinion? Thanks for clearing that up before I put them in my amp.

Have no clue if they are good or not. Never tired those in particular. I was curious to find out who made the tubes or who brokered them. Brokers would be: TAD, New Sensor, Ruby, or Eurotubes (JJ). Manufacturers would be : Reflektor in Russia, JJ tubes in Slovakia, Shuguang in China, TAD is using PSVANE now with the red base tubes.

 

[Mike Lamury]

On closer inspection these are identical to mine except mine have two getter's it looks like the tubes in the pic only have one otherwise identical.

 

[domct203]

On closer inspection these are identical to mine except mine have two getter's it looks like the tubes in the pic only have one otherwise identical.

That’s interesting, the hunt continues.

Dom

 

[bandit2013]

The mica spacers look different to me. Yeah, the single getter vs dual. Does not mean that it cannot be done with a Special Tube Request (STR). I doubt it is from Reflektor plant as they generally do not do the dual getter thing except on the STR441 tubes. Since TAD was having Shuguang make their power tubes, the 6L6GCSTR tube had dual getters and black shiny plates with no holes, looks very close to the STR415 but those tubes are gray plates. As for the dual getter EL34, I see no reason they were not produced by Shuguang. They made tubes for many other brands with some changes here and there. Sort of like the Reflecktor plant in Russia that makes tubes for NewSensor under several brand names. Some are different but most are the same thing. The only other player back around 2000 were Svetlana Electron Devices, AKA SED =C=, and JJ tubes (they bought out the audio tube from Tesla). PSVane are have been around but they used to get tubes from Shuguang. They are now up an running and producing the Red Base tubes for TAD. Then there was PM tubes. Much the same deal as TAD Germany but a different business model. Mostly Chinese tubes.

https://reverb.com/item/59074172-nos-tesla-el34-power-tube-made-in-czechoslavakia
As it is an STR tube, it may be difficult to narrow down the manufacturer. My guess it was Shuguang made in China as they had a different STR number for the SED=C= EL34 and SED =C= 6L6GC tubes.

 

[clyvediggins]

The 442's are winged =C= 34's for sure. Can't help on the others. What's the word on the 450 siemans in a III?

I grabbed 3 of the last 442 sets from Mesa and my sisters of no mercy knocked over a blue stripe I was working on busting the brand new 440'2/442's and even one of the sockets. I put it away for another day when I am not as disgusted.
It was an excited moment and one of the sisters had a bad leg that ended up doing her in so I blame no one but myself.

The 442's are winged =C= 34's for sure. Can't help on the others. What's the word on the 450 siemans in a III?

I grabbed 3 of the last 442 sets from Mesa and my sisters of no mercy knocked over a blue stripe I was working on busting the brand new 440'2/442's and even one of the sockets. I put it away for another day when I am not as disgusted.
It was an excited moment and one of the sisters had a bad leg that ended up doing her in so I blame no one but myself.

Howdy,
Attaching a few pics of tubes I just received from Nesstone. I ordered el34 448’s but received these 442’s. From what I’ve read these are winged c tubes, whatever that means? People seem to like them though. Anyone know if these would work in my TC100?
Anyway got the details of the order worked out with Craig, seems like a good dude. 448’s on the way and I’ll send back the 442’s, but was considering paying the difference and keeping 2 pairs of these. Any feedback on these tubes and my amp would be greatly appreciated.
Thanks

 

[domct203]

Any Mesa branded 6L6GC/EL34/EL84 tube should be fine in your amp.

The =C= (winged C) EL34 is a great sounding tube, you should try them in your amp before you send them back. They are no longer in production and are a much sought-after tube.

Dom

 

[electric mayhem]

Howdy,
Attaching a few pics of tubes I just received from Nesstone. I ordered el34 448’s but received these 442’s. From what I’ve read these are winged c tubes, whatever that means? People seem to like them though. Anyone know if these would work in my TC100?
Anyway got the details of the order worked out with Craig, seems like a good dude. 448’s on the way and I’ll send back the 442’s, but was considering paying the difference and keeping 2 pairs of these. Any feedback on these tubes and my amp would be greatly appreciated.
Thanks

I paid 200 a pair from mesa for the winged =C= when they still had them so that screw up was immensely in your favor.

The 6L6 winged =C='s (STR 454) were considered the 2nd best 6L6GC in the world in the 80's (and on) behind the STR 387, aka 415 if there was a mesa label on them. For that claim I'm not including the old RCA and GE (or TS and mullard).

The winged =C='s were made in St Petersburg by SED as 387 copies and without getting into Svetlana vs SED they are recognizable by the flying saucer top getters and the =C= label if they weren't re-labelled. Like the 387 the =C= is a very musical tube.

The 454's held up to the 105 tranny in the IIC+ (as do the 415's but they were running out) and to the tranny's of the coliseum. They are what came in my IIC+ coli which is one of the last ones made. Afaik JJ is the only 6L6 that still can take that abuse and I've heard differing opinions on the state of whether the TAD can still take that abuse.

 

[clyvediggins]

I paid 200 a pair from mesa for the winged =C= when they still had them so that screw up was immensely in your favor.

The 6L6 winged =C='s (STR 454) were considered the 2nd best 6L6GC in the world in the 80's (and on) behind the STR 387, aka 415 if there was a mesa label on them. For that claim I'm not including the old RCA and GE (or TS and mullard).

The winged =C='s were made in St Petersburg by SED as 387 copies and without getting into Svetlana vs SED they are recognizable by the flying saucer top getters and the =C= label if they weren't re-labelled. Like the 387 the =C= is a very musical tube.

The 454's held up to the 105 tranny in the IIC+ (as do the 415's but they were running out) and to the tranny's of the coliseum. They are what came in my IIC+ coli which is one of the last ones made. Afaik JJ is the only 6L6 that still can take that abuse and I've heard differing opinions on the state of whether the TAD can still take that abuse.

Thank you guys for the info/advice. I’ll check them out and try to scrape up the funds if I like them. Think I’ve already spent my tube allowance for the month… maybe

 

[domct203]

I sent Mesa a message via their zen-desk asking if they also made an EL34 with the STR-448 designation. If they reply I’ll let you know.

I haven’t reached out to them since Gibson acquired them, before that they didn’t work in the office on Friday, and would take a few days to reply. Let’s see how Gibson handles it’s customer requests.

Dom

Just to update my experience with customer service via Zendesk or email.

I have yet to receive a reply beyond a blank reply from Zendesk.

I emailed info at mesaboogie dot com a few days later with my question and never received a response.

Before Gibson’s purchase I would get a reply directly from Mesa within a few days, every time I reached out.

I may try calling next week, just for my curiosity.

Dom

 

[clyvediggins]

Just to update my experience with customer service via Zendesk or email.

I have yet to receive a reply beyond a blank reply from Zendesk.

I emailed info at mesaboogie dot com a few days later with my question and never received a response.

Before Gibson’s purchase I would get a reply directly from Mesa within a few days, every time I reached out.

I may try calling next week, just for my curiosity.

Dom

That’s strange cause I’ve recently gotten responses within a day, or the following working day. It’s always been the same guy Kris Dilbeck. Here was his response on that tube

 

[domct203]

I got a reply, it was blank. I reached out to the email address in the reply and have yet to get a response.

Dom

 

[Mike Lamury]

I'm just curious, did you guys decide that these are indeed EL34's and not 6L6's? I'm able to walk now so I'm wanting to switch these out with the stock 6L6 tubes in my Mark V 90. I'm not so much worried about what brand they are but I don't want to put the bias switch set to the wrong tube. Can anyone tell for sure these are indeed EL34 or 6L6?

 

[bandit2013]

I doubt Mesa would print EL34 on the tube if it was not an EL34. If it was a 6L6 tube, they do not have all the pins in the socket. Unless it is a really old tube, Pins 1 and 6 will be absent from the base so it will only have a total of 6 pins. (not sure when they started to omit the unused pins but it was long before 1980). An EL34 will have all 8 pins on the base.

Still it is surprising they would reuse the STR number for two different types of tubes. Lends to confusion.

 

[domct203]

Post #53 confirmed EL34, but no record of who made the tube.

Dom

 

[Mike Lamury]

I bought two quads of the nis EL34 str448 tubes and when I put one of the sets in the Mark V 90 the caution light on the back of the amp came on even though I had the bias set to EL34 and the power switch on variac power. What does this most likely mean? Are the tubes bad?

 

[domct203]

Caution light?

This one, above the bias switch?

Because the amp was designed and comes with 6L6GC tubes that light goes on whenever the bias select switch is set to EL34 mode so you know it’s in EL34 bias setting.

They could have done a better job explaining that, especially in the manual. I see how easy that could be interpreted as you did.

No worries, if you are running EL34’s and in EL34 bias mode that light is supposed to be on.

Dom

 

[Mike Lamury]

Thank you. Ya it didn't say anything about that in the manual that I remember. They should print that on the back of the amp.