EL34 options Radford STA25

[WESTLOWER]

I was led to believe that changing the power valves (EL34s) in my Radford STA25 mk3
Wouldn’t give much if any change in presentation due to the circuit used.

But ... I had the opportunity to swap out the valves to KT77 (gold lion) over the weekend.
I didn’t much care for the results, just a bit too ommphy for me (although I didn’t give these new valves long and I suspect things may have changed given time?)
Anyway they were only on loan.

But they were certainly different to the JJ El34s

This quick experiment has stoked my curiosity into EL34 options
And if ‘better’ results can be had with different EL34s, either new or NOS..

I am currently using the JJ brand valves that came with the amp,
which in all fairness sound good to these ears but I’m intrigued..

Any thoughts?!
Appreciated

[mik_rik]

Russian 6p3se (preferably gold grid types).Sound good and a helluva lot cheaper than nos Mullards.

[CliveG]

This quick experiment has stoked my curiosity into EL34 options
And if ‘better’ results can be had with different EL34s, either new or NOS..



Not sure about "better" results but I certainly hear differences on my STA15.
NOS Mullards - best mid-range, my overall favourite for all genres.
NOS TESLAs - tighter bass, punchier than the others and my preference for rock and jazz.
NOS Svetlanas - lighter more delicate sound but very pleasant to listen to, best with classical and female vocal.
I found other cheaper options to sound surprisingly good, so the amp design may well iron out a lot of the differences between valves, but some experimentation with NOS may bring you some improvements that you like.

[WESTLOWER]

Not sure about "better" results but I certainly hear differences on my STA15.
NOS Mullards - best mid-range, my overall favourite for all genres.
NOS TESLAs - tighter bass, punchier than the others and my preference for rock and jazz.
NOS Svetlanas - lighter more delicate sound but very pleasant to listen to, best with classical and female vocal.
I found other cheaper options to sound surprisingly good, so the amp design may well iron out a lot of the differences between valves, but some experimentation with NOS may bring you some improvements that you like.

Interesting Thanks Clive.
It obviously its expensive experimenting NOS so your notes on the brands helps a lot.

just don't want to make costly mistakes, obviously.

[Vrajbasi]

I have been collecting tubes for many years currently have around 500 el34 tubes the main production countries were netehrlands and Blackburn, some were labbled as Brimar, mullard, phillips and Valvo.

As far as Mullards go I like the ones from around 1957 to 1962 they have a double ring getter the base wise much wider than the glass itself the bases them self can vary. I found the ones without the guiding pin sound best they have a sense of ease and openess in the midrange which is very nice.

The more common tube is the brown base Mullard where the base is the same size of glass. I have seen the exact tube with the Valvo and brimar logo they sound the same to my ears this tube says made in black burn production was up to 1968. The sound is way more congested and thicker than the earlier tube. It is still very musical.

The 1954 with the code 5x kek flat ring el 34 with the large metal base and flat getter is a great tube I have seen the same tube as a Valvo and brimar its a very powerful sounding tube amazing base needs a adaptor to work.

Dont get me started on 300b and 211 tubes now they can really drive me potty.

I have learnt without trying them in ones system its very difficult so sadly costly mistakes become the norm when trying to find perfection.

There are many many variants I could write about some have different logos etc. I like the Phillips tube with the code xf3 lx lxx with its bakerlite base now this is one beast of a el34 its so so fleshed out in the midrange comes out and simply hugs you. The bass is deep and controlled the top is sweet and liquid. This tube was made in Sittard Netherlands I have not seen this as a mullard or brimar etc. The more common Phillips tube is the one with xf4/5 again stunning.

There were some rare german production el34 tubes that had a flat ring getter I have some not even sure who labbled them they say made in germany I have a code of SYA DX. I think those are great very robust not soft and rounded very controlled.

[WESTLOWER]

I have been collecting tubes for many years currently have around 500 el34 tubes

Nari... I only need 4 !! :lol:

[Edward]

Adam, I'll get the same once you decide.

I'll trust your judgement once you have tried variations of all the possibilities. [emoji23]

§

[WESTLOWER]

Adam, I'll get the same once you decide.

I'll trust your judgement once you have tried variations of all the possibilities. [emoji23]

§

Damn! I was hoping you'd take the plunge and loan me for a night!!

[Barry]

Not the same amplifier, but I use a matched quartet of Mullard (Blackburn Road) EL34s in my Radford STA15 Mk.III. The Radfords were designed with Mullards in mind and that's what I use.

(Despite that, the small signal valves in the amp are Telefunken and Siemens & Halske.)

[IHP]

Hi Adam,

I have the very same amp and did the very same thing (tried GL KT77 in place of the JJEL84). First of all I'd say that I find JJs to be mighty fine and reliable tubes as well as being great vfm. I did find I preferred the Gold Lion - I won't go into detail but they seemed to emphasise the 'modern' sound the Radford has, which does appeal to me. Having said that there was so little in it that I did wonder why I'd bothered sometimes !

I haven't really got a conclusion other than from this and past experience tube rolling can empty a pocket quickly with no huge leaps forwards. The bottom line is that I believe the STA 25 will sound tremendous with any valves that are performing to spec.

[montesquieu]

Russian 6p3se (preferably gold grid types).Sound good and a helluva lot cheaper than nos Mullards.

I used these in a Leben CS660p to very good effect. However I'm not sure if they are a direct EL34 equivalent (more like a 5881?) So might not work in a Radford.

[Ali Tait]

You may find the front end valves will make more of a difference than the power valves.

[mik_rik]

I have used them(6p3se)without any issues for 10 years or so in my STA15,a quick google search (el34 vs 6p3se)will tell you what other people who use them think of them. I agree Ali, rolling the front end valves can give a bigger bang for the buck

[Barry]

The JJ EL34s are an exact copy of the Mullard/Philips design. The Russian equivalent is the 6P27S (sometimes marked in Cryllic as 6П27C).

[WESTLOWER]

You may find the front end valves will make more of a difference than the power valves.

ooh ! Now it's getting very interesting and another mine field...
Any recommendations for these tubes ?

[Barry]

ooh ! Now it's getting very interesting and another mine field...
Any recommendations for these tubes ?

I use Telefunken and Siemens & Halske brands for the small signal valves; will have to check which are used where, as I'm not using the STA15 at the moment.

[WESTLOWER]

I use Telefunken and Siemens & Halske brands for the small signal valves; will have to check which are used where, as I'm not using the STA15 at the moment.

Yes that would be good info Thanks Barry.
the Tubes in it atm don't have markings me thinks.

Be good to get the most from it..

[Edward]

You may find the front end valves will make more of a difference than the power valves.

Prompted by this thread I remembered that I had got some new input valves for my STA25 but had never used them (lazy old git syndrome). Anyway got them in earlier today and shocked by the difference they made. Was using Mullard EFF86 and unknown 6U8A. Replaced with new (not NOS) Phillips EFF86 and Phillips 6U8A. The Mullards were old and probably had thousands of hours on them.

The new input valves gave a tighter sound all round, slightly brighter and more forward sound. And also some more detail. All very positive. :cool:

[Lawrence001]

I didn't know Phillips still made EF86 the only recent ones I've seen are Russian (or rebranded Russian) with the pinholes rather than mesh plates.

Sent from my POT-LX1 using Tapatalk

[Ali Tait]

Prompted by this thread I remembered that I had got some new input valves for my STA25 but had never used them (lazy old git syndrome). Anyway got them in earlier today and shocked by the difference they made. Was using Mullard EFF86 and unknown 6U8A. Replaced with new (not NOS) Phillips EFF86 and Phillips 6U8A. The Mullards were old and probably had thousands of hours on them.

The new input valves gave a tighter sound all round, slightly brighter and more forward sound. And also some more detail. All very positive. :cool:

Good news. Always good to have known good spares to check against what you normally use. They can go off so gradually that you don’t notice.

[Ali Tait]

ooh ! Now it's getting very interesting and another mine field...
Any recommendations for these tubes ?


What valves does it use?

[WESTLOWER]

What valves does it use?


6U8 / ECF82s

EF86 / 6J32P

[Barry]

I've just had a look at my STA15 III. The EF86s are Siemens and the ECF82s are Telefunken. I do have a complete set of Mullard valves for the amp as back up, but I came across the alternatives cheaply and just popped them in.

Can't say I've done any serious tube rolling - but as others have said, the Radfords sound great regardless of valve manufacturer; though based on the experience of the guys at Chelmer Valve Company (whose premises are not far from me), Chinese valves need to be carefully screened for quality, so I would tend to avoid them.

[Ali Tait]

6U8 / ECF82s

EF86 / 6J32P

I’d probably go with what Barry is using. I’ve not experience with either of those but any of the well known NOS makes will be worth trying. Some research would be a good idea imo.

[WESTLOWER]

Cheers chaps.

[IHP]

I certainly agree with the comment regarding signal valves having more influence on sound. I can't recommend these on the basis of comparison with other valves as I haven't 'rolled', having bought them on the basis of NOS at what I considered to be a reasonable cost, but all sounds mighty fine to me.....

https://www.ebay.co.uk/itm/EF86-6267-GENERAL-ELECTRIC-NOS-VALVE-TUBE-LC21/273793225428?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

https://www.ebay.co.uk/itm/6U8A-GE-ECF82-NEW-OLD-STOCK-VALVE-TUBE-1PC-S15/391257852340?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

Anyway, just for your interest ;-)

[Wakefield Turntables]

Interesting thread! I've just realised I'm in exactly the same position, I'm rolling EL34's in my Radford. I dug out my old STA25 and had a good listen. I couldn't remember what I'd plumbed in earlier but had a blind listening test. Several hours later and I'm very happy with my results, turns out they were Electroharmonix :eek:. I've been looking into vintage American valves and may even try some of the JJ's considering that they are an exact copy of the old Mullards. I do have some old Mullard 34's but I'm not sure how strong or matched they may be. JJ's have a good reputation, I liked the JJECC83's when I tried them in my Radford Pre, but ultimately went onto a batch of NOS Mullard ECC83 yellow labels (even though the JJ's were supposed to be an exact copy of the Mullards :doh:). Oh, decisions, decisions!