REPLACEMENT VALVES ,
UNAUTHORIZED "GREY" IMPORTS,
& CIRCUIT DIAGRAMS

Customers question is :-
> I've owned an EL34 for 3 years
> and I'm very content with the amplifier.
> Just recently the little gem has gone off the boil a little.
> I've changed all the valves but this has not cured the problem.

YOU CANNOT BUY VALVES FROM ANYBODY
AND SHOVE IT INTO OUR AMPLIFIER !

Valves and transformers are the most expensive and
IMPORTANT components of a valve amplifier.

SO, YOU CANNOT BUY VALVES FROM ANYBODY
AND SHOVE IT INTO OUR AMPLIFIER !

When the bass disappears after every 2 or 3 years,
(at 3 hours use a day)
you have to replace the valves.

Our cost for the owner of our amplifiers is :-

£50 for 4 "PROPERLY MATCHED" piece of Svetlana EL34 valves
+ 4 pieces of American Military 5670

Svetlana EL34 have an excellent reputation for sound and reliabilty,
so why use anything else ?

£160 for 4 "PROPERLY MATCHED "piece of Svetlana KT88 valves
+ 4 pieces of American Military 5670

It is very tedious to match valves properly.
We have to "burn in" the valves for 24 hours, before we even start !

We do NOT sell our valves
to reduce the distortion of our competitors amplifiers !

YOU HAVE TO TELL US THE "HAND-WRITTEN" NUMBER
WRITTEN ON THE VALVES,
AND BUY REPLACEMENT VALVES FROM US.

You also have to tell us the serial number of the amplifier and the "model" of the amplifier. ( This can be found at the back of the amplifier. ) If you bought it 2nd hand, you have to tell us the name of the original owner.
If you bought it from a shop, many years ago, you have to tell us the name of the shop.
Shops want hundreds of pounds of profits & did not pay us,
so we have stopped selling to shops.

There are a number of ?clever? people who have bought unauthorized "grey imports".

We refuse to have anything to do with unauthorized "grey imports".

If you have a problem with with unauthorized "grey imports",
you should sort it out with the person who sold you the unauthorized "grey imports".

MATCHED VALVES
& Why you have to buy valves from us

Some suppliers of valves are useless at matching valves.

        -- Either --
They either do not know how to match valves,
          -- or --
They could not be bothered
          -- or --
They know how to match valves, but they could not be bothered,
( or did not have enough valves to match properly. )

If you have 100 valves, you have an excellent chance of finding 4 similar valves.

If you only have 5 valves, then there is only a SMALL chance of finding 4 similar valves.

We have to reject many sets of "matched" valves.

Then, we have to match up the "rejected" valves ourselves,
AFTER WE PAID THE SUPPLIER TO MATCH THE VALVES !

You should NOT use "unmatched" valves,
regardless of what some people say !

Please do NOT listen to the distributor of an American brand
who told a Hi Fi reviewer that
you can use "unmatched" valves in the American Amplifier !

Yes, it can work,
but you will get lousy distortion !

"PROPERLY MATCHED" valves will reduce distortion (without feedback).

This is important for MOST valve amplifier,
that uses SMALL amounts of negative feedback,
to reduce distortion.

There is NO virtue in ANY distortion, wherever the distortion comes from valves,
transistor, loudspeakers, CD players (at -60 db) or cartridges fixed to your turntable !

FIXED / ADJUSTABLE BIAS
& Why you have to buy valves from us.

Our company and many "Hi End" companies, like McIntosh, Conrad Johnson & Audio Research,
use "fixed / adjustable bias"

The disadvantage of "fixed / adjustable bias" is :-

we have to send you "similar valves",
so you do NOT have to adjust the bias.

So, you have to tell us the handwritten numbers on the valves
+ all the information stated above

The advantage of "fixed / adjustable biased" is :-

1. twice as much power as the cheaper "automatic cathode bias" used in the
old Leak Stereo 20 , old Quad II and most old English amplifiers.

        2. faster recovery from any overload
             (at very high volumes which will cause PERMANENT damage to your hearing,)
             ( if you play it at that level, for many hours everyday. )
             ( When you overload amplifiers with cheaper "automatic cathode bias" )
             (the cathode capacitor will change up & change the bias towards "class B" )

         3. better bass slam
                    (You do not have to roll off the bass at 50 Hertz,
                   (and then get the bass back by negative feedback.)
                   ( This weakness is linked to point 2 above ! )
                    (Increase the size of the "cathode capacitor to get deeper bass, )
                    (and it takes longer to recover from any overload.)

Question from customer
> Could you please supply a PDF format circuit
> diagram so the problem could be investigated further.

If you did NOT already know the above mention facts,
please leave our amplifier circuits to the professional.

Why do some people think
they know more about valve amplifiers than us ?

We really hate it when amateurs think that
they can ?improve? our amplifiers.
If amateurs know so much, they should build their own design,
and leave our amplifiers alone !

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