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tannoy man
03-11-2010, 15:52
Can anyone help me make a decision as to what valves to buy.
I bought my radford 2 years ago in non working condition, it has now been sympatheticaly restored and will be back with me next week.
I cant afford NOS Mullards and would prefer to buy new, these are my options so far.
Electro Harmonics EL 34
Gold Lion KT 77
Electro Harmonics 6CA7 Fat Bottle
Siemens EL 34 NOS
New Sensor Corporation Mullard EL 34 Reissue
The prices for 4 of these range from £50 to £120
Matching ancilliaries are Croft Micro Basic and Tannoy Ardens mk 1
Thanks Paul

Epicurus
03-11-2010, 16:46
I'd be inclined to go with Electro-Harmonix. I hear they've got a good reputation and they're easy to obtain.

DSJR
03-11-2010, 16:50
I wouldn't worry too much, as the Ardens will stamp their signature on anything further back - LOUDLY if possible :)

I'm not criticising Ard-ons by the way, in any shape or form. I'm serious about the valves though, as I suspect the Radford will be kind to any that you fit and the make of valve won't make or break the sound, in the same way Glenn Crofts amps seem valve-immune to a large extent.

Marco
03-11-2010, 16:50
Hi Paul,

If no-one else answers this, I'd PM the likes of Spendorman (Paul), hifidave, or Anthony TD, as they all have significant experience in this area :)

Marco.

tannoy man
03-11-2010, 18:09
Thanks.
PS forgot to mention I paid £120 for the Radford PRE, POWER and a pair of Lowther Accoustas. The seller delivered it all to my workplace then made a quick exit. on checking the Lowthers I found one driver missing the guy thought he.d shafted me.:lol::lol::lol:

worrasf
04-11-2010, 11:09
Hi there.
While I have no experience of your particular amp I do have loads with valve swapping/tube rolling my Croft 25R and Croft Series 4s so may be able to give some pointers.

IMHO steer clear of Electoharmonix - they are keenly priced but in my system were overly bright and shouty - more suited to guitar amps really.

There is little doubt that NOS valves from 1950's - 70's sound "better" than new production/reissues from any manufacturer. Beware of JJ Tesla - these are mainly new production and IMHO a bit nasty

A quick search of Ebay revealed some Mullards and Tung Sol at good prices. And some stunning Telefunkens at a bit more.

There are a quad of Svetlana's for £94 http://cgi.ebay.co.uk/EL34-SVETLANA-WINGED-C-NOS-MATCHED-QUAD-/310210519022?pt=UK_Consumer_VintageAudio_RL&hash=item4839fcdfee#ht_500wt_1099
which would be excellent.

Looks like you got the amps for a very keen price so I really would suggest holding out for some good NOS valves - you wont regret it.

IMHO despite what some might say the sound from different valves varies enormously and there is no doubt that you can shape the sound by swapping various valves. I've certainly spent more dollar on valves than the amps themselves and more time and effort "getting them right" than any other tweeks but it's well worth it. I settled on NOS GE 6550's NOS Telefunken EL519's, original TESLA E83CC's, JAN GE 12ax7's GE 12BH7's and the piece de resistance a 1955 ULM manufactured Telefunken ECC801s

There is always the worry with NOS valves that they will be "dead" or of short life but in my experience I have never had a duff one. I bought a valve tester just for peace of mind in this regards.

Very happy to advise if you are looking at specifics although as I say no direct experience of your kit. Hope this is of some help

Best of luck

Steve

worrasf
04-11-2010, 11:25
Meant to include this link in previous post.
http://www.jacmusic.com/KT88/kt88.htm

I have found the info on this site invaluable when looking out for valves various and trying to avoid pitfalls - never knew there was a shady market in forging valves:eyebrows:

Regards
Steve

tannoy man
04-11-2010, 20:27
Iv looked at the Svetlanas. I,l probably get them, cheers.

John
04-11-2010, 20:46
Agree with Marco Spendoman or Anthony T would be the people I go to

spendorman
04-11-2010, 21:40
My STA25 III has JJ KK77's in, very happy with them. I also have GEC KT77's, can't tell the difference in sound between the JJ and GEC KT77's. However the GEC's are a ridiculous price if one can get them. I also have the original Mullard EL34's which are still fine. They and the GEC KT77's are in storage.

Apart from the JJ KT77's, my STA25 is completely original. It has never needed anything. I can't think exactly how long I've owned it, but it is probably around 35 years.

spendorman
04-11-2010, 21:52
Thanks.
PS forgot to mention I paid £120 for the Radford PRE, POWER and a pair of Lowther Accoustas. The seller delivered it all to my workplace then made a quick exit. on checking the Lowthers I found one driver missing the guy thought he.d shafted me.:lol::lol::lol:

Brilliant purchase, pre amp SC2, SC22 or something else?

About 35 years ago, think I paid £150 for my STA25 III, SC22 and FM tuner. It was second hand, but in very good condition.

If yours is an early STA25 III, it may not be fitted with the mod to reduce mains transformer mechanical noise. If you find that you get a noisy transformer, details of the Radford mod are on the Yahoo Radford Newsgroup. Alternatively, send me a PM and I will email it to you.

tannoy man
04-11-2010, 22:16
Pre is SC22 and its a later Series 3, I havent had the pre serviced, is it worth doing? I"m thinking of selling it
Very impressed with my croft micro basic, so will have to see.

spendorman
04-11-2010, 22:24
Pre is SC22 and its a later Series 3, I havent had the pre serviced, is it worth doing? I"m thinking of selling it
Very impressed with my croft micro basic, so will have to see.

I think that the SC22 is very nice. Certainly needs to be checked out if it has not been used for a while.

My friend has a very rare STA20 (yes 20, not 15 or 25) which is used with either an SC22 or a Quad 77 pre. He likes both and says not much to choose between them in terms of sound quality.

tannoy man
11-11-2010, 17:52
Just to let you know I bought NOS Siemens from Langrex, £109 good price.:)

spendorman
11-11-2010, 17:55
Just to let you know I bought NOS Siemens from Langrex, £109 good price.:)

Not bad at all.

Will be interested in how it sounds.

tannoy man
07-02-2011, 21:00
Just to let you know Alex the Siemens are well burned in now and I have nothing but praise for them, absolutly liqued midrange and the top and bottom leave me gobsmacked.

kt66
08-02-2011, 14:41
I'd be inclined to go with Electro-Harmonix. I hear they've got a good reputation and they're easy to obtain.

No way! the Siemens are amazing, made by Telefunken , I'd say the EH are the worst of that list