Tagboard insulation failure in Quad II amplifier

[Murphyv310]

Of course "If" the customer insists, plus if you are happy enough doing it that way then who am I to put you off. It's all down to what you are comfortable with doing.
Over the years I have done work from Devon to Aberdeen, I no longer advertise due to word of mouth referrals plus three or four a year is enough for me. I hate repeat jobs, they are a total pain so that is why I do it the way I do. Being honest I do loose the odd one and have pointed those people to your website VB, I'll never know if you have gotten any work from these folk or not. Hopefully you have

[Valvebloke]

Most of my lot seem to have heard about me from previous customers, or through the hifi fora, but as you say we sometimes just don't know.

The owner of the current amp is retired now but he used to work with my brother. He earned his living in IT but he's a physicist by training. So he does have his feet on the ground when it comes to the technicals, which makes a nice change. I should say that I sent him a link to this thread back at the start of it.

VB

[Terry]

A friend sold some EL34's to a Hi-Fi nut who said they had to be Mullard as they were the only ones ever made that were "sonically perfect".  

If the EL34s were branded 'Philips' (the parent of Mullard) or any of their other offspring and, possibly had the same batch code as the Mullard branded specimens, would they have been acceptable and - if not - why?

[Valvebloke]

Since we don't know the 'nut' (there's that word again) in question, I guess we'll have to speculate. The answer's "Maybe yes, and maybe no" of course.

Assuming the factory codes are good, so these valves really were produced at a decent Philips plant and at a time when they were still making them in large enough volume for QA to be up to scratch, and assuming the buyer understood this and believed it, then if he only wanted the valves for his own use most of the hi-fi folks I've met would probably be happy from a 'sound' point of view to take any Philips valve. Indeed, only last week one of my customers asked if I had any Mullard GZ34s for sale. I had to say no, but I told him that the vast majority of old stock GZ34s, whatever they were branded, were made by Philips/Mullard and if he ever gets the chance of a Tung-Sol or even a Zaerix he should check the factory code, because it might well be 'the real thing'. He left saying he'll do this, and I honestly believe he will.

Some folks might say no though on grounds other than sonic. First they might not like the look. If they've got three good Mullards in the amp they might want the fourth one to be a Mullard to get a visual match in much the same way that if you ever need a door replacing on your car you'll probably want it to be the same colour as all your other doors even though you know, don't you, that its colour won't make a trace of difference to its performance   . The same could be said for knobs on radios. They're knobs for goodness sake. Surely only nutters care whether they match.

Other folks might want a branded Mullard because if they ever decide to re-sell it, or sell the amp with it in, they know that a valued brand will be worth more. Hard cash is a really compelling argument. Really compelling ! (It's actually less of an issue with power valves because they don't hold their resale value very well. But there's quite a healthy market in second-hand small-signal valves because as a general rule those don't go downhill very quickly in hi-fi amps. Guitar amps and tellies are a different matter of course.)

As a closer I'll raise the hoary old issue of 'sonic'. Hi-fi people mostly don't care about 'sound' as vibrations of the air, or voltages and currents in amplifiers. They care about the sensation they get in their brains when those vibrations move their eardrums. That sensation is influenced by a lot of things other than the air vibrations. One of the strong influences is the hi-fi fan's sense of comfort and well-being about the kit he's using to reproduce the music. Never mind how it's actually working. What affects the sound in his head is how he feels it's working. If it's got the 'wrong' valve in it and that's irritating him then it will never 'sound' perfect.

VB

[Terry]

It is, of course, quite possible to find Mullard branded valves that were made at, say, Philips, Eindhoven or Valvo, Hamburg.

Equally, an identical valve branded Philips or Valvo might just as easily be made at Mullard, Blackburn!

We used to buy some of our valves from a small wholesaler who took the order and filled it in the back of his van. Half an hour from order to delivery can't be bad, can it?

All his valves were branded Tungsram - which was not a BVA mark but the prices were 10% cheaper than the BVA valves we got from other wholesalers.

Every single one of his valves, of course, came from a Philips group factory ...

[Mike Watterson]

I've got a radio with American "Mullard" valves. I think as well as selling Continental made Philips under their own brand from not long after 1928, the Amerty valves (tubes?) are late 1930s to early 1950s? Were they all RCA or a mix?
Anyway BVA seemed to have been more a UK based sellers cartel than actually to do with where the valves were really made? Were all Brimar UK made or some USA?
I don't know. The last two officially sanctioned cartels in UK and Ireland were book prices and pharmacies. Wholesale set Retail pricing ended quite recently. Governments used to actually support and enforce cartels, strange as it seems today.

[Pat Pending]

I just love a chestnut this time of year

Cheers,
Andy.

[Mike Watterson]

Or a Mice Pie :D