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Old 27th Oct 2014, 12:08 pm   #21
GrimJosef
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Default Re: The cost of that ECC83 valve?

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Originally Posted by PE9ZZ_JO22KI View Post
... Why pay a fortune for a NOS diamond base TFK ECC83 when a clone (Chinese, JJ, whatever) will do the job exactly the same way? ...
But will it ? The TFK ECC803S is an exceptionally high spec valve. Here is the datasheet http://www.jacmusic.com/nos/ECC803S/...TELEFUNKEN.pdf. Does your Chinese clone have the same microphonics as the frame-grid Telefunken ? Does it have a lifetime of 10,000 hours ? Has the cathode surface been engineered to withstand very long periods in standby ? Are both halves of the Chinese valve exceptionally closely matched ?

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Old 27th Oct 2014, 1:31 pm   #22
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Default Re: The cost of that ECC83 valve?

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The high mu double triode made by Brimar and used by Rogers was not the ECC803, it was the ECC807.
I stand Corrected GJ I DID mean the 807's I must have had a slight brain attack!
To the other poster the PCL86 is identical to its ECL counterpart, (as is the PCL82 to ECL82). Agreed the UL/PL 84 etc etc have lower Va and power ratings and should not be treated as substitutes.
I have just checked the JJ valves that came with my World Designs Kit phono stage and they are ECC803S, but I think thats just a marketing ploy. They do work just as well as any other decent ECC83/12AX7.
And as a final Caveat, from personal experience a lot of alleged "NOS" Mullard valves etc do not seem to be very robust or go noisy very quickly. I suspect a lot of what would have been "Reject" stock back in the day has found it's way back on to the market and found a willing clientele. Not just my theory, a couple of friends who have been in the business a long(ish) time also think this.
By the way GJ, the PCL86 valves are for a project amp loosely based on the Rogers Cadet circuit using those nice Radiospares Hygrade transformers I bought from you at Tonbridge earlier this year. Seemed a shame to use them in a SE EL84 amp, I used a couple of pulls from a scrap amp for that.
Regards to one and all,

Andy
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Old 27th Oct 2014, 4:34 pm   #23
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Default Re: The cost of that ECC83 valve?

@GrimJosef: Your point is valid. The "spanngitter" ECC803S is totally different from the original box plate ECC83. The electrical specs however are exactly the same. It's the construction that's completely different. The TFK ECC83 (also diamond bottom) is the conventional construction, not frame grid. The JJ ECC803S is also conventional and thus a fraud. It's a rebadged ECC83. I'm well aware of the JacMusic article. Very informative, a must read!

@mark pirate: I'd love to see that! Only it won't happen. These people see a coveted label and thus it must "sound" better. They'll miserably fail a double blind test.

@Tyso_Bl: just start a new topic. Who knows...

Tjerk, 9ZZ
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Old 28th Oct 2014, 2:06 am   #24
Lucien Nunes
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Default Re: The cost of that ECC83 valve?

As most of us here are technical types, we habitually try to analyse the boutique audio field. However as it is mainly one of aesthetics, it can only be looked on holistically as a source of enjoyment. It often breaks down into nonsense when dissected to piece parts and tech specs, just as the fun of a night at the casino does not stand up to purely mathematical scrutiny. There is certainly a lot of snake oil in high-end audio too, but there is so much more to the genre than just snake oil that we should not dismiss it out of hand on that account either.

The problem when trying to eke out dwindling shared resources is not that either field is an unworthy consumer of them, but that we compete with very uneven economics. The HiFi man probably only needs two ECC83's, and when he splashes out on a nice pair with just the right colour of printing, their value is added to the total value of his system. One of my old musical instruments - and bounty hunters please take note that it is an exceptional case and most are not like this - has about 90 ECC83s. Yet its value as a complete machine is about nil, even with a full complement of the juiciest ECC83s. As you can imagine, very few of these survive, and they are some of the rarest and most valuable worthless items in my collection!
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Old 28th Oct 2014, 11:42 am   #25
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Default Re: The cost of that ECC83 valve?

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Originally Posted by Lucien Nunes View Post
As most of us here are technical types, we habitually try to analyse the boutique audio field. However as it is mainly one of aesthetics, it can only be looked on holistically as a source of enjoyment ...
Yes, exactly. And people enjoy owning 'nice' things.

The other major error is to try to analyse the demand side on the basis of what people need rather than what they want. Failing to understand that in a luxury market (and hobbies really are a luxury) demand is driven hardly at all by need and almost entirely by want will stop anyone's career in marketing from progressing beyond square one .

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Old 28th Oct 2014, 12:03 pm   #26
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Default Re: The cost of that ECC83 valve?

It's a question of degree and proportion in the end. Most of us would be mildly pleased to find ECC83s in a rummage box at a rally- they are, after all, a useful beastie per se, apart from any boutique considerations. We'd be a bit more pleased if they were identifiably Mullard construction, if they had plenty of getter and otherwise didn't seem brutalised or tired, better still. Being in retail boxes would be a step further. Beyond this, we're getting into the grey area where getter ring shape and anode stamping profile would excite some and inspire snorts of derision in others, i.e. where science and art have their boundaries. A very individual thing.
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Old 28th Oct 2014, 12:12 pm   #27
G8HQP Dave
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Default Re: The cost of that ECC83 valve?

Anecdotal evidence says that:
- modern valves don't last as long as NOS
- modern valves are more likely to be noisy or microphonic than NOS
- modern valves have less good vacuum than NOS (so higher grid current)
- modern valves don't adhere so closely to the datasheet values/graphs as NOS
- modern valves have poorer heater-cathode insulation than NOS (hence the modern trend for DC heaters)
- modern valves with Western labels may actually be Eastern (Russian or Chinese) designs which in some cases were only reasonable substitutes rather than near-equivalents (heater currents and voltage/power ratings may be different)
- some modern valves even have poorer pin size tolerances than NOS (surely this is by far the easiest thing to get right?)

Hence you can't always guarantee that a modern valve can be used to replace an old valve. Sometimes it will be fine, sometimes it won't.
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Old 28th Oct 2014, 3:02 pm   #28
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Default Re: The cost of that ECC83 valve?

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Old 28th Oct 2014, 11:30 pm   #29
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Default Re: The cost of that ECC83 valve?

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Originally Posted by G8HQP Dave View Post
- modern valves have poorer heater-cathode insulation than NOS (hence the modern trend for DC heaters)
I thought this was due more to wanting to minimise hum in pre-amp stages?

Cheers

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Old 30th Oct 2014, 10:55 am   #30
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Default Re: The cost of that ECC83 valve?

I am not certain why £100 for a genuine Mullard NOS ECC83 should be regarded in any way as expensive. Obviously people have not bought spare parts for Kubota engines, or Apple power supplies, or lots of other parts that seem outrageously expensive now.

Note the use of the words genuine, Mullard and NOS above. I really wonder if they really exist now. The Sale of Goods Acts require a seller to be truthful, and I really can't imagine how any seller can actually GUARANTEE that any particular high worth valve is really NOS. After the fiasco of the selling of the BAOR equipment in the early 90s, ALL government items have been sold, since the mid 1990s, by agents. There have been no sales of boxes of valves to buyers other than through these agents. I have been buying here for 20 odd years, and have yet to see any boxed NOS valves appear for sale. What there has been is lots of test equipment with valves in it, even today it turns up. These units have had almost no use, and the valves look as new when removed, and are they then promptly sold as NOS? I have bought a small amount, but this was only just the odd percent of the total.

When buying a NOS valve, make sure you get a certificate of authentification from the seller, stating how they KNOW it is new. You won't get one.

Are modern valves really the same? There has been much discussion about that on both this and other forums. In particular the tendency for power valves to object to high voltages, you get an internal firework display. Why? The conclusion seems to be that the cathode is shedding it coating. I have tried to find out just what this means, with very little success.

A valve is a simple mechanical construction, if the bits of metal are exactly the same size then the characteristics will be exactly the same. The killer is the cathode coating. From books such as Fundamentals of Vacuum Tubes by Eastman or Theory of Thermionic Vacuum Tubes by Chafee you find that the cathode coating really is a black art. By no stretch of the imagination is it trivial. The mix of coating ingredients, the laying on to the cathode substrate, the subsequent heating, curing and activation consume a lot of time and energy. Is this followed by modern manufacturers? Umm. Then there is all the problems of degassing the metal, something that has also appeared on this forum, and was new to me then, most useful, thanks.

My search for the details of valve construction has turned up very little information, if anyone can suggest other books I would be most interested. There are lots of papers in the technical journals but they seem to have all gone, now unavailable. In particular I am trying to find out exactly what the physical dimensions of the structure affect the performance of the final valve. For example, by tightening the grid coil spacing by 5% say then the grid bias is reduced by 5%, by reducing the grid wire diameter by 5% then the grid bias is increased by 5%. These are just examples, I just don't know, but if anyone can provide any information then I would be very interested.

There is no doubt that a valve in its entirety is a precision piece of manufacturing, and the skills have been lost. Ok, you can make a valve, bit of bent metal and some rare earth coatings, but I rather doubt it corresponds in any way to what Mullard etc managed in the 1950s. Of course, the modern manufactures may publish technical papers, I haven't found any though. Does this affect how it sounds? No idea, suffering from tinitus really doesn't help my cloth ears.
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Old 30th Oct 2014, 12:00 pm   #31
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Default Re: The cost of that ECC83 valve?

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Originally Posted by woodchips View Post
... Note the use of the words genuine, Mullard and NOS above. I really wonder if they really exist now. The Sale of Goods Acts require a seller to be truthful, and I really can't imagine how any seller can actually GUARANTEE that any particular high worth valve is really NOS ...
The last TFK ECC803S that I bought was in its original box which was still tape-sealed. Forging this ancient tape would have taken some skill and effort. I was as sure as I could be that this valve really had never been out of its box. Amusingly there are valves doing the rounds out there which still have the tape seals intact, and people are paying a premium price for this guarantee of NOS-ness. Given the cost I'm afraid I was just too wary to buy a valve this way. I asked the seller if he would be prepared to risk breaking the tape and letting me measure the valve before handing over the money. True gent that he was he agreed even though, had it measured badly, he would have been left with a valve worth a lot less than it was before. In fact it measured absolutely perfectly and we were both delighted .

Cheers,

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Old 30th Oct 2014, 12:15 pm   #32
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Default Re: The cost of that ECC83 valve?

I think woodchips has pretty much nailed it.
personally I got disillusioned with, in particular "NOS Mullard" ECC83's as every single one that I bought, back when they could be got for £15 or so, sadly not now, either failed or went noisy (gassy?) in the EAR Phono Stage i was using. However that stage, as I found out from a study of the circuit diagram, used a series heater string which may have put individual stresses on valves that may have deviated from the 150mA heater draw.

I have had better success with stuff like "NOS" Amperex etc which on closer scrutiny has turned out to be Philips or other "quality" manufacture. I do believe there was a lot of Vlaves sold under a different label to the actual manufacturer even back in the heyday of Valves?

So I tend to buy NOS only if the prices seem reasonable as its a gamble.

And notwithstanding the scepticism from certain quarters, my personal experience with JJ, Electroharmonix, and also the Chinese "Golden Dragon" brand from PM components, certainly for small signal valves has only been good. On the whole.

Andy.

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Old 30th Oct 2014, 1:08 pm   #33
G8HQP Dave
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Default Re: The cost of that ECC83 valve?

Quote:
Originally Posted by bikerhifinut
I do believe there was a lot of Vlaves sold under a different label to the actual manufacturer even back in the heyday of Valves?
The printing on the outside of a valve tells you almost nothing about the gubbins on the inside. Stock was routinely swapped for various reasons. Some valves were only made by a few factories, but labelled by all the main suppliers. For example, you can buy a 'Mullard' ECC804 but every one I have seen was made by Brimar/Mazda and is identical to their 6/30L2.
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Old 30th Oct 2014, 1:57 pm   #34
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Default Re: The cost of that ECC83 valve?

On Saturday, at a rally, one for 50p.

I don't know whether it's good or not, but I'm slowly collecting a spare set for my EA12 and I found a few interesting ones on a stall. A VR150/30 for the AR88 and there was a box of OA2s unfortunately the one I pulled out was a DL91 I found later. No use to me so it'll get passed to someone who needs one.

Anyway the ECC83 was British made. I never looked for a Blackburn code, or the shape of the getter. I don't care, I just want a radio to work if I ever need to use it.

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Old 30th Oct 2014, 2:28 pm   #35
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Default Re: The cost of that ECC83 valve?

Woodchips makes some good points - if many of the valves being sold as NOS are actually low-mileage pulls then that may explain why they seem more reliable than new valves - they've been soak tested (G8HQP_Dave)!

As to old telly (P series) valves - I've made lots of experiments on NOS (allegedly) and pulls and most are serviceable in an amplifier though if AC is used on the heater expect more hum and the need for a heater lift to improve it. In most of my HiFi amps I've gone for DC feeds to the heaters but I've not bothered with the hassle of regulators a couple of diodes and a big capacitor are enough and in those cases P series valves are nicer in that the currents are lower.

I suspect that the impression that NOS is better may be down to various factors not least of which is that most have been tested or are low-mileage pulls.

I bought a set of "Willow valve" ECC84's for a headphone amp and one of the set was very microphonic and a bit low that's a 20% failure rate - I'm fairly sure they were new as they came in a sealed five-pack...I suspect that there were a good number of DOA's and hardly used returns when valves were mainstream.
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Old 30th Oct 2014, 6:19 pm   #36
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Default Re: The cost of that ECC83 valve?

Willow Vale were not the highest quality rebranders - I suspect that some of their valves were seconds: for example, functional but leaning sideways (Pisa style).
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Old 30th Oct 2014, 6:39 pm   #37
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Default Re: The cost of that ECC83 valve?

I have some valves that are genuinely NOS.
I bought them in the 50's or 60's direct from the makers / suppliers, and still have them.
I doubt that I am the only one, so some of the NOS probably are.


As for valve prices, my general rule is that if I am buying, they cost a fortune, but when I am selling, they are worthless.
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Old 30th Oct 2014, 11:04 pm   #38
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Default Re: The cost of that ECC83 valve?

It seems to me you have 2 choices with the ECC83.
You fish about for a bargain used old stock or take it on the chin and buy a rare NOS if originality is important.

Or,

You buy a new modern manufacture ECC83 for between £8 to £15 a pop. (just a quick riffle through common retailers gave me those numbers).
How long they last may never be an issue it depends how hard you run em surely? My take these days is to run the heaters at 6V rather than 6.3, i dont think emission is that far down at that voltage.

The topic is only for the ECC83, I have been pleasantly surprised recently to find "proper" 6SJ7 and 6SL7 at very reasonable prices so there must be a few of those around still.
Andy.
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Old 1st Nov 2014, 12:27 pm   #39
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Default Re: The cost of that ECC83 valve?

Don't know whether it's just the NZ market, but a lot of the high valve prices over here are being caused by guitar valve amp enthusiasts who refuse to believe that the new 12AX7's etc are as good as the old ones. Things like 'the modern Chinese KT88 knockoffs cannot take the high plate voltage (650v) of Marshall 200 watt amps and explode like firecrackers' are things I've seen on websites devoted to the minutae of the older valves. I can't but help think its all nonsense but they are willing to pay ridiculous sums for NOS. Just wish I'd kept the audio output EL34's to sell them from all the old TV's I ratted - LOL.
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Old 1st Nov 2014, 12:37 pm   #40
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Default Re: The cost of that ECC83 valve?

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Don't know whether it's just the NZ market, but a lot of the high valve prices over here are being caused by guitar valve amp enthusiasts who refuse to believe that the new 12AX7's etc are as good as the old ones ...
It's not just in NZ. Exactly the same factor applies here (it's actually not hi-fi people, I think, but guitarists who set the top prices for Mullards). It seems that after a while spent practising they run up against the fact that they still don't sound like Jimi Hendrix or Stevie Ray Vaughan. They're then forced to the conclusion either a) that they simply don't have the combination of talent and commitment that JH and SRV did or b) that there's something wrong with their kit. It's surprising how many decide it must be b) .

Cheers,

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