Opinions on New Production EF86?

[bob p]

I'm looking for some info on current production EF86 for use in the first position of a HiFi tube amp. I haven't kept up to date regarding the new production EF86, but I seem to remember a thread on the old Ampage site that mentioned reliability problems and microphonics with current production EF86 -- to the extent that it seemed that no decent current-production tubes were available.

I just wanted to ask if anyone has had experiences with current production EF86 by any of the manufacturers, and whether experiences were good or bad. I'm about to take on a HiFi amp building project on behalf of a friend who's on a budget, and he'd prefer to use new production tubes if any suitable ones are available, as the old ones are getting kind of pricey -- especially if you want to keep spares on-hand.

thanks.

[Chris / CMW amps]

I do have good results with modern (but rebranded) ones from Ruby and TAD.

Compared to some noisy and microphonic old Philips ones the sound was slightly warmer to my ears.

Hope this helps.

[J Martin]

I have had good results from the Svetlana units. They have caused considerably less trouble than NOS. I don't know of any manufacturer other than the St. Petersburg plant. I bought a whole case of then a few years ago before the price went up.

[soundmasterg]

The Svetlana/Sovtek ones have a reputation as being sometimes way too much gain for what the EF86 should be, and are also microphonic like many EF86's. That said I've never had a problem with one so maybe its a bad rep? Tubg-Sol (New Sensor) has a new EF806, as does JJ. JJ's just came out within a month or two, and the Tung-Sol has been out for at least 6 months. Haven't tried either one so maybe someone else can comment.

[J Martin]

One nice thing is that you can do a whole lot of gain adjustment on the EF86/6267 with the screen resistor alone.

[bob p]

Thanks everyone for their help.

Regarding the new EF806 (I'm not familiar with that tube and I'm assuming that 806 is not a typo), how different are these from the original EF86? For my application in an ultralinear HiFi circuit, renumbering a Russian tube that is close but no cigar, and selling it as an EF86 would create some problems for me.

Although increased gain may be great for a guitar amp, today "gain" doesn't mean the same thing in guitar and HiFi circles, and more "gain" is not always good. It could cause serious problems in a HiFi amp. There's not much point in building a design that calls for an EF86 if EF86 tubes aren't really available. If I have to redesign the entire front end of the amp to accomodate a different tube, what's the point of building a HiFi circuit that calls for an EF86?

FWIW, I've looked at the JJ official site and they don't mention an EF806 or any preamp pentodes.

http://www.jj-electronic.sk

[J Martin]

The EF86 is real and its still being made. I am not familiar with the 806. It seems to be a Euopean tube with no direct American substitute.

I service vintage hifi as well as guitar amps in my shop so I have some experiance.

A few years ago I was concerned about the supply of EF86 and the 6BM8 tubes because my suppliers were out of them, so I spoke to PM Distribution, a European company that distributes the Russian Svetlana and EI brand tubes. They said both were still in production and there were no plans discontinue either tube.

[dai h.]

EF40 might be one to look into. I think it's pretty much the same exact thing but with the weird "Rimlock" base. When I've seen them (NOS of course since no one makes tubes with that weird basing any more) they are usually cheaper than the regular mini 9 pin EF86. Of course you could have a problem sourcing sockets though.

[soundmasterg]

The EF806 is essentially a "selected" EF86. It has tighter production controls and is supposed to be a better performing tube. They also cost more.

Here's the link to the info on the new JJ. Should be to market anytime according to Eurotubes.

http://www.eurotubes.com/euro-u.htm