EF86 - Suggestions on which to buy

[gtrbryan]

My next build will be based on the Ceriatone Creme Brule which looks like a DC30 single channel preamp with a two tube power amp.  V1 is an EF86.  Layout below.

http://www.ceriatone.com/images/layoutPic/CremeBruleeLayout/CremeBrulee.jpg

This is my first use of an EF86 and I read they are very inconsistent (and expensive).  Any suggestions on one to purchase?  Also, any substitute suggestions are appreciated as well (I realize I would have to change the pinout).  As alwyas, thanks to all.

[tubenit]

You could consider a 5879 pentode.  Do a search on Geezer's  HoSo56.

You can also make a socket dampener out of silicon to isolate vibrations from the tube.


With respect, Tubenit

[Geezer]

5654 is another option....same Basic gain and tone as the 5879, but less microphonic in my experience. Not that the 5879's are so microphonic in the first place..... not nearly so much as the EF86s.

G

[Backwoods Joe]

I've had good results with Steve at http://thetubeshop.com/ . He usually has slightly used (but better than most brand new)Valvo EF86's at reasonable prices. He really checks his stuff and backs it up.

[TIMBO]

Nice little amp, thanks for sharing. I got an EF86 (electro-harmonix) that needs a home.

[tubeswell]

Keep your eye out for good NOS deals of not-so-well-known brands. I got a box of 5 National 6267/EF86 (still in the 5-lot box!) the other day for NZ$27 (US$22.38) for the lot! Couldn't believe my luck. And they work very well in a combo! (very robust). I've also good luck with Tee-Rad 6267s.

[gtrbryan]

Thanks as always for the good advise.  I'll see what the tube shop has. 

[jojokeo]

EH, JJ, & Tung-Sol for newer tubes are all okay. Even Shuguang/Svetlana/Sovtek are not too bad which I believe the good Dr. even used & supplied w/ his new production amps.
I have a preference for the older tubes though like Mullard/Phillips/Amperex/Valvo/Telefunken types but you have to be careful with these on the microphonic issue or run them at a lower gain level to address this (which they still perform great this way anyway).

[clyde]

I'd have to disagree on the Tung Sol EF86's.  I find their tone to be lacking and reliability very poor.  The JJ's are somewhat better but NOS is really the only option here.

[Backwoods Joe]

Clyde thanks for the Tung-Sol info. I've been fortunate with the German & UK mesh plate tubes (EF86)s. One of my customers just bought a NOS Tesla off ebay. It is identical to the JJ ef86.

[jojokeo]

ditto, but I did say "okay" which means what it does. I don't consider these as "bad" tubes though and better than nothing or relying solely on high priced NOS tubes which is what was the case not too much more than a few years ago. It's nice that new tubes are being made which has created the renaissance for the pentode amps being made in recent years and maybe they'll approach the older "mesh tubes'" qualities someday?

[tomcatarnold]

12AX7 front end options:  https://taweber.powweb.com/store/cascode_schem.jpg

[jojokeo]

12AX7 front end options:  https://taweber.powweb.com/store/cascode_schem.jpg

Options for what? Have you built any of these? If so, which?

[clyde]

I also am hoping that quality will improve.  The gold pin EF86 from Tung Sol is supposed to be the high-end tube and indeed has a high-end price.  The latest one I used went south in an amp in less than 45 minutes and I don't over-dissipate them.  For what I pay for 2 of these I can easily buy one NOS or ANOS Mullard and be saved the ragged tone on top of it.  I use the EF86 simply because new production is available but I may have to rethink this unless the bar is raised. 

[jojokeo]

I actually haven't tried one of those but I do like their 12ax7s & 6v6s a lot. I can't recall losing a tube in "normal" use before. But I have abused some and dropped a few. About 6 months ago I scored a few beautiful NOS RCA 5751s for super cheap (easily worth +$25 to $35 ea) and I had to see them in the light shining through my kitchen window they were so clear, clean, and perfect. Ofcourse I had to bumble finger them onto the hard ceramic tile floor below...

[clyde]

Ouch!  My sympathies, that's tough to take. 

[HotBluePlates]

Keep your eye out for good NOS deals of not-so-well-known brands. I got a box of 5 National 6267/EF86 (still in the 5-lot box!) the other day ...

Be very careful with National (Richardson Electronics). National and Richardson were simply re-branders, and you might have anything from an American or western European tube to modern Russian or Chinese stuff. There's just no telling with them.

One of my customers just bought a NOS Tesla off ebay. It is identical to the JJ ef86.

JJ bought a part of Tesla's manufacturing equipment. Too bad most of the knowledgeable engineers are gone. So it's conceivable that some JJ tubes will look just like older Tesla tubes.

The gold pin EF86 from Tung Sol is supposed to be the high-end tube and indeed has a high-end price.

You're only paying extra for the gold plating on the pins. I personally wouldn't buy any modern tube just because of the gold pins. Old-production tubes did use gold pins on some premium versions which were truly better in a number of ways than the prototype tube.

5654 is another option....

I might have to beg you to save those 5654's (and 6AK5's) for me! I haven't used them in a guitar amp, but have some tube-based Hewlett-Packard test gear which uses them.

[tubeswell]

Keep your eye out for good NOS deals of not-so-well-known brands. I got a box of 5 National 6267/EF86 (still in the 5-lot box!) the other day ...

Be very careful with National (Richardson Electronics). National and Richardson were simply re-branders, and you might have anything from an American or western European tube to modern Russian or Chinese stuff. There's just no telling with them.

These ones have the silver mesh shield surrounding the other electrodes and red writing on the bottle which is prone to rubbing off. At $27 for a lot of 5, I ain't complaining