Latest 300b valves

[Rexton]

Guys, I need a new pair of 300b's but I'm stuck with respects to which is best out of the new variants. Do you have any experience or suggestions?

[Rexton]

Tumbleweed ….. a dearth of replies.

[pre65]

HotRox have a selection.

How much do you want to spend ?

The cost effective favourites used to be Electro-Harmonix 300b gold.

[Nick]

Yep, the problem is what you regard "best" as meaning.

[simon]

It's perhaps 10+ years since anyone here was playing with 300Bs. I stopped after a rather unfortunate incident with a KR300BXLS one Christmas eve . This might explain the lack of replies?

How deep are your pockets? The Elrog 300Bs at £1345 a pair are reputed to be as good as it gets by some, though I suspect anyone paying that sort of money for valves would be convinced of their merit.

https://www.mcru.co.uk/product/elrog-er ... cba1185463

[IslandPink]

I don't know if KR's are still around, but I have nothing but good to say about mine - still going strong after over 10 years.

[Rexton]

Thanks. I'm already aware of Hotrox, Langrex, Watford valves etc. I've been using Golden Lion but the build quality is shocking. Just out of interest, what have people been playing with (valve wise)? I'm afraid I've been quite boring and only had experience with Ecc83's, EL34's, KT88's, 6SL7's, and 300b's. I'm always keen to see what the latest flavour of the month.

[steve s]

Px4 and px25 are my favourites, but I have a pair of stc 4300a, which sound better than most 300b that they have been pitched against

[andrew Ivimey]

I've three 32bs which were the pre-cursors to the 3000bxs. Gave up using them or 300bxs, or EHGG300Bs or Shiagangs for GM70s - just can't go wrong.

[pre65]

Yes, GM70 or GK71 are well worth a try.

If you are brave then 833a (GU48) could be interesting.

[Nick]

Personally if you feel bravery is needed, it means there is uncontrolled risk. Never a good idea IMHO. If you need the power a 833 can give you probably have the wrong speakers. If you are just making the same power a gm70 will, then a gm70 will be cheaper and need far less compromise in output tx and power supply. Gm70 is in a nice spot between a 211 and 845 and cheaper than both.

[Ali Tait]

As far as 300b at a sane price are concerned I don’t think you can go wrong with JJ.

[IslandPink]

Don't forget GK-71 in triode, which needs a somewhat less B+ and is even cheaper. There's still the problem of the filament supply ... but the quality seemed to be better than my KR300B's when tried.

[Thermionic Idler]

Sorry, only just seen this thread - I built a pair of 300B push-pull monoblocks in 2020 as a lockdown project, and they've been our main amps ever since.

I sourced the 300B's as matched pairs from here: https://brimaruk.com/valves/triodes/brimar-300b/

Now obviously these are re-branded Chinese-manufacture and I have no idea where they came from originally, possibly Shuguang? I also run them quite conservatively, IIRC about 60mA / 350V plate in line with Western Electric spec.

With those operating points, they have probably given us at least 4000 hours of service by now, and still going strong. Sound-wise they are wonderful. although full disclosure - I have not tried other 300B brands yet. But these seem reasonably solid, reliable and long-lived.

I'm one of very few people here still using the things - but I love them to pieces, the key thing is to drive them properly - 6SN7's won't do, they pretty much need a small power amp valve behind them - I have triode-connected 6V6's as driver valves in my design with a good 4dB+ headroom between driver and output stage. Many commercial designs don't do that so a lot of the time you're hearing a distorting driver stage, hence the 300B's sometimes poor reputation.

[Mike H]

Very interesting!

Just personally, have had best luck with GuiGuang, which became Psvane and much more expensive! Gold plated pins I think, black anodes. Been 'burned' with others that are sometimes nasty and don't last 5 minutes – once a quad of Svetlana's started failing before I could pay off the credit card! More recently my preferred alternative is 801A originally bought from Langrex (but he doesn't seem to do them anymore), but I see they're stupid money now as well! (Just checked, eBay etc.) Yikes...