EH EL 34's

[tjdjr1]

Made it 54 weeks on the EH El34's before one had fireworks display. Going to try some Ruby EL34b str's this go round. Maybe it's me but when I gigged 3 weekends a month and rehearsed in between gigs years ago, I could get a lot more playing time on tubes. Back then I ran Svetlana, JJ, and Tesla tubes and ran an amp much harder than these days.

[briman]

Yeah today's tubes are hit and miss in regards to quality. I had a brand new Ruby red plate on me once, JJ redplated after 2 months and a brand new EH pre amp tube microphonic right out of the box.

Have had 0 issues with Tung Sol however. Used EH el34's for long time with no issues either.....only the pre amp one time.

[chickenbeard]

My amp guy swears by these tube store preferred series. I have them in mine, sounds good, though I am not a tube expert by any means.

www.thetubestore.com/preferred-series-el34

[tjdjr1]

I looked at those preferred series seem like good tubes, but with 6 month warranty doesn't say much. I find it difficult to determine what may be better we have maybe 3 or 4 places making tubes and 10 or more brands selling them. Does preferred series/GT/Gold Lion and others really re-screen tubes to find the best who knows... It's a coin flip anymore. Sad!

[gtrjunior]

At my last tube change I tried several brands. JJ 6CA7, Mullard RI etc.

You know what ones sounded best to my ear? The Chinese EL34 B that came stock in the amp. I got them from tube depot.

The original tubes lasted a little over a year and these new ones are maybe 6 months old now. So far no issues.

I have found that a gigging player should expect to change tubes about once a year (give or take).

[gtrjunior]

Oct 31, 2018 6:46:25 GMT -5 tjdjr1 said:

I looked at those preferred series seem like good tubes, but with 6 month warranty doesn't say much. I find it difficult to determine what may be better we have maybe 3 or 4 places making tubes and 10 or more brands selling them. Does preferred series/GT/Gold Lion and others really re-screen tubes to find the best who knows... It's a coin flip anymore. Sad!

I think a 6 month warranty is great. 3 months is the average. Even Scott only warrantees his for 90 days.

[tjdjr1]

Received the new Ruby's today and 1 was DOA! WTF ! Put them in and instantly the bad one went red like now. Called MF going back. I wound up taking out a new set of EH's from the 2203. So are burned in tubes the best bet to insure all in the set are good to avoid this crap ?

[splawndude]

I am not the expert here but there is something to be said about buying tubes from someone who has already tested them out in a real amp. Not just putting them in a tester. Laura, the valvequeen.com does this. When I bought my SED =C= (winged C's) she told me she would test them in her Nitro and I believe her. I would also feel comfortable in buying tubes from Dougs tubes for similar reasons. He is the one who turned me onto the 5751. Then you've got Bob at Eurotubes. I've bought stuff from him too but I was never really one to buy into all the snake oil of tubes which he seems to sell a lot of. I also found some of his videos to be misleading and sometime dangerous. Other outfits that I have no direct experience would be KCANOS valves, The tube store, Tube depot, AMS, etc - but I don't know if all of these guys actually test the tubes in amps or what they are doing. If no ones takes the tubes out of the boxes and actually tests them then they are not adding any value in the value chain.

There is no such thing as a burned in tube. There is something to be said for a tested tube though.

Keep in mind, it is possible for a tube to go south just in the fact that it is being shipped so there is that too.

[gtrjunior]

I have been using tubedepot.com exclusively for quite a while now. I have never had a bad experience.
In the past I’ve bought from Doug’s and eurotubes as well.
All of them are top quality retailers.
I live in New England and tube depot is located in TN. Shipping is fast.
As a matter of fact I ordered new filter caps and a duet of power tubes for my Marshall yesterday...it was marked as shipped and I had a tracking number within an hour.

[splawndude]

I asked Doug once for a tube recommendation and he replied immediately. It was something like JJ, Penta Labs 9th Gen, and a 5751. I pulled the trigger and he texted me that they had shipped and they arrived the next day or so. This was like 5 years ago - do not have any recent knowledge. I wasn't even in a hurry to get them.

PS: I had some Guitar Center credit left over so I went in there the other day just to see what I could find. I ended up buying 2- GrooveTube 12AX7s and a Tung Sol 12AX7. Yes Tung Sol. Thought I'd give it another chance since I seem to dog them so much

Also got a Boss Looping pedal. The small red one. For fun.

[briman]

I recently bought kt66's and 4x 12ax7's all Tung Sol from tubedepot and sound awesome.

[tjdjr1]

How much variance do you guys see from tube to tube or side to side with the bias readings? I also noticed the tubes sockets seem a bit loose any way to tighten them up ?

[splawndude]

You can have tube sockets tightened. Not sure on the exact process but you can google it if you don't get a good answer here. Not sure what you mean by variance in power tubes. Do you mean from a new quad set?

[gtrjunior]

I think he means how much of a difference do you see when you put the bias probe on each tube.

Short answer
When you buy power tubes you should always buy a matched set. That means their tolerance will be very close to each other.
Since there is only one bias pot on the QR you can’t adjust each tube individually.

[splawndude]

Yeah. That's right.

A tube guru told me once that to avoid cross-over and bad distortion try to keep them all within +/- 4 maA.

That and (in most Marshall style amps) the outer two work as a pair and the inner two tubes work as a pair.