Valves... what, where, how....

[Farmitou]

Right I completely confused by the world of valves... as this forum seems to have the best cross section of hifi users I'd like to know your opinions.

1. Do different valves change or improve the sound.

2. If so... how do you know which to use and where to get them... is it amp specific, with different valves having different reactions to different amps or do they have the same characteristics in different amps.

3. Again if so... do different manufactureres of the same valve have different characteristics.

I'm new to valves and really enjoy the sound of my equipment, but as a long term goal, wish to improve it if possible. With the cost of some valves being so high ant to know if it's all hype first.

Thanks guys 🙂

 

[Farmitou]

No thoughts on this guys? 🙂

 

[tino]

I think you'll find most of the answers out there by trawling the internet or joining a dedicated Yaqin forum, unless anyone on this forum has specific experience of your amplifier. Make a note of which valves your amplifier uses (300B etc.) and search on that name/type. You will probably find comparisons of different manufacturers of those types of valves and they will probably list the quality / audio characteristics that each type might have.

A lot of people swear by NOS (New Old Stock) valves ... valves that were made many years ago e.g. Mullard, but still new and unused. NOS valves are reported to be better than some of the newer valves you can buy today ... probably because they were built during a period when manufacturing knowledge / processes / quality were at their peak.

 

[Anonymous]

Yes NOS valves usually get a good recommendation. Many were made during the Cold War era and used in Russian communications and spy equipment so you'd expect the old Soviet regime to be pretty keen on good quality kit in their fishing trawlers (spy ships)

 

[chebby]

A lot of people swear by NOS (New Old Stock) valves ... valves that were made many years ago e.g. Mullard, but still new and unused. NOS valves are reported to be better than some of the newer valves you can buy today ... probably because they were built during a period when manufacturing knowledge / processes / quality were at their peak.

A 1960s company film about Mullard valve production in Blackburn....

http://www.youtube.com/user/A2MGape#p/c/5779B0E3D60DB5CE/0/xnvKCC6_VDQ

 

[eggontoast]

1. Do different valves change or improve the sound.

Valves from different manufacturers will change the sound, whether it is an improvement is going to vary from person to person.

2. If so... how do you know which to use and where to get them... is it amp specific, with different valves having different reactions to different amps or do they have the same characteristics in different amps.

Most of the time yo must use the specific valve type that the amplifier was design with however valve numbers vary from country to country eg UK ECC83 - America 12AX7 - UK military CV4004 all have the same characteristics and are interchangeable. There are various online stores, some will grade, match, test, cryogenically treat them or just sell general purpose. A couple of examples of on line retailers are The Tube Shop in Kent, Watford Valves etc

3. Again if so... do different manufacturer's of the same valve have different characteristics.

No, the characteristics are the same but the internal construction to achieve these parameters are different.

I'm new to valves and really enjoy the sound of my equipment, but as a long term goal, wish to improve it if possible. With the cost of some valves being so high ant to know if it's all hype first.

As some previous post mention NOS valves get raved about, it is true that they were built more consistent. The materials in valve construction are critical and is one area where quality control would have been enforced in the golden era of valve manufacturer. Whether they sound better is going to be subjective from person to person. Current valves from New Sensor (Sovtek, Electro-harmonix, new production Mullard, Svetlana, Genalex, Tung Sol) are all made in the same factory the Xpo-pul/Reflector factory which is an old Russian miitary plant and they suffer from quality issues. The Svetlana (SED) factory in St Petersburg make the best current valves (with regards to consistency, durability, longevity). JJ electronics in Slovakia make a wide variety of valves and are continually adding to that list, they use the old Tesla designs and equipment to manufacturer there valves, unfortunately there consistency is variable. Finally the last big player is the Chinese Shuguang factory, they make fairly consistent valves. You will also see E.I. valves for sale these are not in manufacture now as the factory in Yugoslavia folded in the late 90's. There are also a few small 'boutique' manufacturers such as Western Electric.

 

[Farmitou]

Thanks Guys... questions answered! I've googled and there isn't too much about rotation and best matches with my equipment, so I guess it's just a case of trial and error. I'm going to wait to after the christmas madness then will report back with my opions and findings.

Again thankyou!

 

[Farmitou]

Hey Guy

Couldn't ait to after christmas and ordered a few different valve to test different sounds and valves, the ones that fail sonically will go back on the flea bay... I've googled but can't find anything on my amp about adjusting the bias. So simply does anyone know how to?

I'm new to valves and love the sound so wouldn't go back, but simply don't want to mess up the equipment whilst experementing 🙂.

The Amp has Bias test and adust which should simplify matters but I'm still lost 🙂

 

[eggontoast]

If you don't mind me asking what have you purchased ?

FYI you only need to re-bias if you replace the power valves, have you brought power valves ?

 

[Farmitou]

I've gone for 47 triangle plate Sylvania 6SN7GTB for the CD player as there strongly recommended on a few forums for this model.

As for the amp...

2 x 300b-z treasure tubes, 2 matched (Angled Black Plate) 6SN7GTB Tubes By Sylvania (manufactured for Rogers) , a matched pair Sylvania 6SN7 GTB and a Phillips Hollland 1950's 5R4GYS Type ~ 274B rectifier.