Tube Rolling

[Fran]

Yes, here be monsters.

Some circuits are sensitive to it, others not - so results can be unpredictable.

Just be careful about substituting different types, eg 12au7 is not the same as 12at7 or 12ax7. Even where pinout is the same, be careful of current draw of the heater. Good example is substituting a KT88 for a EL34 - pin out matches, but the heater f the KT88 needs more current. If the power transformer isn't specc'd high enough to give the juice, it will burn out.


Fran

[Diapason]

Okay so, all joking aside, I need to buy some new 6922/E88CC valves and I'd like to not spend vast sums of money for no reason. Perusing ebay, I came across the Russian equivalent 6N23P-EV (sometimes called 6H23n-EB) which sell for "competitive" prices, and seem to be reasonably well-reviewed, and certainly considered a step up from the ubiquitous Sovtek 6922. Anyone ever tried any of these?

I'm reluctant to spend any more than about €20 a valve (and to be honest, I'd prefer to spend a lot less than that). Any other recommendations?

I also need EF184's but they seem much cheaper.

[Fran]

The russian ones are usually very good, and better than the chinese ones. Just be sure that they are the same as each other (not just pin out, but also current draw for heaters, max plate voltage etc etc) - go to tubedata.org for the datasheets.

I've used a variety of sellers on ebay, the ukrainian ones mainly, but also "yitry" on ebay, who is actually langrex valves in the UK. Jim Mcshane in the US is a very decent fella to deal with, but probably will be a bit dearer than ebay.

Example: I built a phono stage, uses 6SN7 (russian 6H8S) and 6N1P. The russian 6H8S sounded better than the RCA 6SN7 I had, and the plain jane vanilla 6N1P sounded better than the higher spec version 6N1P-ev.

FWIW, the -EV (-EB) in russian means that they are mechanically stronger, usually they have thicker glass at the base. There's another suffix thats used, can't recall it right now, and it means they are tighter tolerances I think.... maybe I have that the wrong way around.

Fran

[Diapason]

Thanks Fran, that tallies with a lot of what I've read online. I'm going to have a chat with Cloney's valve guy (Bernard) as well.

[Ivor]

I've said it before and being a bore I'll say it again. Expensive tubes are not nessessarily better than cheap ones. Tube equipment relies on synergy in a system to sound good, cheap might well work best. Do the homework and if you find recommendations for your amp (with similar source and speakers) then start there. Good luck and I wish you patience.

[Diapason]

Indeed Ivor, and I'm intent on finding the cheapest acceptable option for 'set and forget' but thus far I haven't found many things that count as cheap. The Russians seem well-regarded, reliable, and they really are cheap, so that might be my first port of call. I've no interest in the madness here. For once!

[Diapason]

Just checked and I only need 4, not 8. That's a good result.

[fergus]

Just checked and I only need 4, not 8. That's a good result.

Money saved already!!!