THE BILL MAY REPORT

Buying the best output transformer

Should you choose on measurements, reputation or price?=20
Bill May explains how professionals evaluate transformers.

Your average audiophile is lucky if he gets to hear two or three output
transformers before he makes his choice. It probably takes him a lot of
time and organization to hear that many.

So how does he make his choice? There are only three ways: listening to
enough transformers under controlled conditions to make a choice,
buying on measurements, and buying on recommendation.

Listening to one or two or three isn't really enough. For the test to
be meaningful, the transformers must be installed in duplicate amps, or
at least in very similar amps. For the choice to be meaningful, the
transformers must be installed in an amp very similar to what the user
will build.

He can study manufacturer's spec sheets. Some manufacturers lie, or
take their measurements in such a way that they are not truly relevant
to any real-life amplifier. That's before the hype even starts. Those
who read the hype can easily be misled into thinking there is a single
figure of merit for a transformer. It can be bandwidth, low bass
extension, power handling. It isn't true. Any transformer that will
sound good has all its desirable technical features in balance.

The hype includes the price and the reputation of the transformer. That
makes sighted tests suspect to any engineer.

He can ask for recommendations. The problem is that those who recommend
a particular transformer may have heard only that transformer, or
perhaps one other, and possibly not in suitable amplifiers. Or the
recommendation may be informed by nothing more than spec sheets and
hype.

In the end, only relevant, blind listening tests count.

This doesn't apply only to the average audiophile. Even professionals
can be taken in!

Here is an example of how measurements, hype and blind tests can
produce different results These tests were conducted to choose the
output transformers to be used in an amplifier Real McCoy Audio was
designing for Japanese manufacture. The manufacturer intended us to
choose between the six most expensive Japanese transformers. The
cheapest Tango, the Swedish Lundahl, American Magnequests and British
Audio Note UK transformers were added as statistical controls, and the
no-name potted Chinese and open-frame Russian ones as placebos.

The electrical ratings are for weighted results of measurements taken
in circuits optimized to the transformers. In the sighted tests
knowledgeable listeners were permitted to see the transformers and were
told their relative prices, if they asked. I have included a price
scale, on which 1 is expensive and 5 is cheap. In the blind tests
no-one in contact with the listening panel knew which transformer was
being evaluated. The sighted tests were conducted after the blind
tests. Several of the tests were repeated with a different listening
group to confirm the result.

TEST RATINGS OF 13 OUTPUT TRANSFORMERS

Rating Measurements Sighted Blind
1 Tango 1 Tango 1 Lundahl 3
2 Lundahl 3 Tango 2 Nature Sound 1
3 Tamura 1 Tamura 1 Tango 2
4 Nature Sound 1 Nature Sound 1 Tamura 1
5 Nature Sound 2 Magnequest 1 Tango 1
6 Tamura 2 Nature Sound 2 Nature Sound 2
7 Tango 2 Lundahl 3 Audio Note UK 4
8 Magnequest 1 Tamura 2 Tamura 2
9 Audio Note UK 4 Audio Note UK4 Russian 4
10 Magnequest 2 Magnequest 2 Magnequest 1
11 Tango 3 Tango 3 Tango 3
12 Chinese 5 Russian 4 Chinese 5
13 Russian 4 Chinese 5 Magnequest 2

(If the table doesn't look right, select the table text, select Courier
font, reduce font size until it makes four clean columns)

The Measurements column holds no surprises. On measurement, all of
these except the Russian transformer are good performers. Some
audiophiles scoff at the idea that a set of electrical measurements may
predict the outcome of taste tests with certainty. That is true. But if
one lowers the expectation a little, correctly weighted measurements
will at least eliminate components on which further time should not be
wasted. That proved the case here. Of the bottom five in the
measurements rating, only one transformer is not in the bottom five in
the blind listening tests.

The Blind Listening Tests in the last column hold several surprises. A
comparison with the Measurements table shows that the best-measuring
transformer does not always sound the best. Price comparisons show that
the most expensive transformer does not always sound the best, even
within the same brand. The high rating of the Russian transformer shows
that precision is not as highly valued among the musically inclined as
engineers would prefer. The Russian transformer rose so far above its
measurements in the listening tests because its inaccuracies are
aurally pleasing in the "presence range". One of the listening panel
noted in his Comments block: "Who cares about accuracy when you can
have ecstacy."

The Sighted Listening column shows the effect of brand name, hype, and
possibly of appearance. Comparison with the Blind Listening column
shows that some reputations are earned and some are not. The same
comparison shows that an industrial physical appearance can depress the
sighted rating of a transformer like the Lundahl which measures
exceptionally well and in the blind listening tests came first.=20
Equally hype can boost the sighted rating of a transformer, like both
the Magnequests, well beyond its rating in either measurements or on
blind listening. A comparison between blind and sighted ratings of the
Japanese transformers is interesting. It shows that even where
appearance is not a consideration, and the reputation is earned,
knowledge of relative price can distort the rating.

The chief conclusions to emerge from these tests are that with regard
to output selection transformers for listening pleasure and fidelity:

=B7 data sheet measurements and reputation must be supplemented by
other means to predict listening pleasure
=B7 careful weighting of measurements on hand of experience goes some
way towards an initial rough selection
=B7 sighted listening tests are too subject to the effects of
reputation and hype to be used as a predictor of listening pleasure
=B7 blind listening tests prove that some reputations are earned
=B7 blind listening tests prove that a high reputation achieved by
hype is no guarantee of listening pleasure
=B7 blind listening tests prove that high price is no guarantee of
listening pleasure
=B7 blind listening tests prove that an industrial appearance, if kept
out of sight, is no bar to listening pleasure
=B7 blind listening tests prove that a modest price is no bar to
listening pleasure
=B7 success in blind listening tests is not always a guarantee of
fidelity in reproduction
=B7 blind listening tests should therefore always be used
=B7 but only in conjunction with careful interpretation of the
measurements

Incidentally, after examining our results the Japanese manufacturer
chose the mid-price Tango for sonic, marketing and financial reasons.

Bill May spent forty years in high tension electricity supply. A
long-time tube hi-fi enthusiast, he is now technical director of Real
McCoy Audio, a design and prototyping shop.

=A9 Copyright 1998 William May and Real McCoy Audio. May be reprinted
freely on the internet only if reproduced in full including this
copyright and permission notice.
=20

Fran=E7ois Yves Le Gal wrote On 2 May 2005 15:48:43 -0700,
" wrote:

THE BILL MAY REPORT

William "Bill" May doesn't exist : he is another one of your
sockppupets,
Jute. You created it during your ill fated crusade against Magnequest
in
1988.

BTW, Real McCoy amplifiers don't exist, your KISS amp doesn't exist.
You're a sick ****, Jute.

If you want to believe the lies Creepy Mike LaFever of Magnequest tells
you, Toad, I'm sure they'll make you feel better. In fact, if it will
make you feel better, I will confess to not existing either. I am an
artifact of my art teacher's mind with additional dialogue by my
favourite English teacher. Meanwhile, here is Bill May's report again.
It carries the date of first publication in the copyright notice at the
bottom. -- Andre Jute


THE BILL MAY REPORT


Buying the best output transformer


Should you choose on measurements, reputation or price?
Bill May explains how professionals evaluate transformers.


Your average audiophile is lucky if he gets to hear two or three output

transformers before he makes his choice. It probably takes him a lot of

time and organization to hear that many.


So how does he make his choice? There are only three ways: listening to

enough transformers under controlled conditions to make a choice,
buying on measurements, and buying on recommendation.


Listening to one or two or three isn't really enough. For the test to
be meaningful, the transformers must be installed in duplicate amps, or

at least in very similar amps. For the choice to be meaningful, the
transformers must be installed in an amp very similar to what the user
will build.


He can study manufacturer's spec sheets. Some manufacturers lie, or
take their measurements in such a way that they are not truly relevant
to any real-life amplifier. That's before the hype even starts. Those
who read the hype can easily be misled into thinking there is a single
figure of merit for a transformer. It can be bandwidth, low bass
extension, power handling. It isn't true. Any transformer that will
sound good has all its desirable technical features in balance.


The hype includes the price and the reputation of the transformer. That

makes sighted tests suspect to any engineer.


He can ask for recommendations. The problem is that those who recommend

a particular transformer may have heard only that transformer, or
perhaps one other, and possibly not in suitable amplifiers. Or the
recommendation may be informed by nothing more than spec sheets and
hype.


In the end, only relevant, blind listening tests count.


This doesn't apply only to the average audiophile. Even professionals
can be taken in!


Here is an example of how measurements, hype and blind tests can
produce different results These tests were conducted to choose the
output transformers to be used in an amplifier Real McCoy Audio was
designing for Japanese manufacture. The manufacturer intended us to
choose between the six most expensive Japanese transformers. The
cheapest Tango, the Swedish Lundahl, American Magnequests and British
Audio Note UK transformers were added as statistical controls, and the
no-name potted Chinese and open-frame Russian ones as placebos.


The electrical ratings are for weighted results of measurements taken
in circuits optimized to the transformers. In the sighted tests
knowledgeable listeners were permitted to see the transformers and were

told their relative prices, if they asked. I have included a price
scale, on which 1 is expensive and 5 is cheap. In the blind tests
no-one in contact with the listening panel knew which transformer was
being evaluated. The sighted tests were conducted after the blind
tests. Several of the tests were repeated with a different listening
group to confirm the result.


TEST RATINGS OF 13 OUTPUT TRANSFORMERS


Rating Measurements Sighted Blind
1 Tango 1 Tango 1 Lundahl 3
2 Lundahl 3 Tango 2 Nature Sound 1
3 Tamura 1 Tamura 1 Tango 2
4 Nature Sound 1 Nature Sound 1 Tamura 1
5 Nature Sound 2 Magnequest 1 Tango 1
6 Tamura 2 Nature Sound 2 Nature Sound 2
7 Tango 2 Lundahl 3 Audio Note UK 4
8 Magnequest 1 Tamura 2 Tamura 2
9 Audio Note UK 4 Audio Note UK4 Russian 4
10 Magnequest 2 Magnequest 2 Magnequest 1
11 Tango 3 Tango 3 Tango 3
12 Chinese 5 Russian 4 Chinese 5
13 Russian 4 Chinese 5 Magnequest 2


(If the table doesn't look right, select the table text, select Courier

font, reduce font size until it makes four clean columns)


The Measurements column holds no surprises. On measurement, all of
these except the Russian transformer are good performers. Some
audiophiles scoff at the idea that a set of electrical measurements may

predict the outcome of taste tests with certainty. That is true. But if

one lowers the expectation a little, correctly weighted measurements
will at least eliminate components on which further time should not be
wasted. That proved the case here. Of the bottom five in the
measurements rating, only one transformer is not in the bottom five in
the blind listening tests.


The Blind Listening Tests in the last column hold several surprises. A
comparison with the Measurements table shows that the best-measuring
transformer does not always sound the best. Price comparisons show that

the most expensive transformer does not always sound the best, even
within the same brand. The high rating of the Russian transformer shows

that precision is not as highly valued among the musically inclined as
engineers would prefer. The Russian transformer rose so far above its
measurements in the listening tests because its inaccuracies are
aurally pleasing in the "presence range". One of the listening panel
noted in his Comments block: "Who cares about accuracy when you can
have ecstacy."


The Sighted Listening column shows the effect of brand name, hype, and
possibly of appearance. Comparison with the Blind Listening column
shows that some reputations are earned and some are not. The same
comparison shows that an industrial physical appearance can depress the

sighted rating of a transformer like the Lundahl which measures
exceptionally well and in the blind listening tests came first.
Equally hype can boost the sighted rating of a transformer, like both
the Magnequests, well beyond its rating in either measurements or on
blind listening. A comparison between blind and sighted ratings of the
Japanese transformers is interesting. It shows that even where
appearance is not a consideration, and the reputation is earned,
knowledge of relative price can distort the rating.


The chief conclusions to emerge from these tests are that with regard
to output selection transformers for listening pleasure and fidelity:


=B7 data sheet measurements and reputation must be supplemented
by
other means to predict listening pleasure
=B7 careful weighting of measurements on hand of experience goes
some
way towards an initial rough selection
=B7 sighted listening tests are too subject to the effects of
reputation and hype to be used as a predictor of listening pleasure
=B7 blind listening tests prove that some reputations are earned

=B7 blind listening tests prove that a high reputation achieved
by
hype is no guarantee of listening pleasure
=B7 blind listening tests prove that high price is no guarantee
of
listening pleasure
=B7 blind listening tests prove that an industrial appearance,
if kept
out of sight, is no bar to listening pleasure
=B7 blind listening tests prove that a modest price is no bar to

listening pleasure
=B7 success in blind listening tests is not always a guarantee
of
fidelity in reproduction
=B7 blind listening tests should therefore always be used
=B7 but only in conjunction with careful interpretation of the
measurements


Incidentally, after examining our results the Japanese manufacturer
chose the mid-price Tango for sonic, marketing and financial reasons.


Bill May spent forty years in high tension electricity supply. A
long-time tube hi-fi enthusiast, he is now technical director of Real
McCoy Audio, a design and prototyping shop.


=A9 Copyright 1998 William May and Real McCoy Audio. May be reprinted
freely on the internet only if reproduced in full including this
copyright and permission notice.

wrote:


If you want to believe the lies Creepy Mike LaFever of Magnequest tells
you, Toad, I'm sure they'll make you feel better. In fact, if it will
make you feel better, I will confess to not existing either. I am an
artifact of my art teacher's mind with additional dialogue by my
favourite English teacher. Meanwhile, here is Bill May's report again.
It carries the date of first publication in the copyright notice at the
bottom. -- Andre Jute



(-I am loathe to get involved, but I just gotta say-)
----I don't know who Mike LaFever is, but I do know how to use Google.
There is only one return on the search result "bill may real mccoy
amplifiers", at http://www.diyparadiso.com/lundahl/shoot1.htm . There
are no other hits of any significance for " 'bill may' amplifiers", none
for " 'william may' amplifiers", none for "real mccoy amplifiers", or
for any combination of the independent terms "bill william may real
mccoy amplifiers", or even the name "real mccoy" in connection with any
sort of audio business.

Since you can find search results on just about any other company that
ever existed, I'd agree this is a spoof. The GoogleMatrix p0\/\/\nZ you!

On 2 May 2005 18:07:10 -0700, "
wrote:

François Yves Le Gal wrote On 2 May 2005 15:48:43 -0700,
" wrote:

THE BILL MAY REPORT

William "Bill" May doesn't exist : he is another one of your sockppupets,
Jute. You created it during your ill fated crusade against Magnequest in
1988.

BTW, Real McCoy amplifiers don't exist, your KISS amp doesn't exist.
You're a sick ****, Jute.

If you want to believe the lies Creepy Mike LaFever of Magnequest tells
you, Toad, I'm sure they'll make you feel better. In fact, if it will
make you feel better, I will confess to not existing either. I am an
artifact of my art teacher's mind with additional dialogue by my
favourite English teacher. Meanwhile, here is Bill May's report again.
It carries the date of first publication in the copyright notice at the
bottom. -- Andre Jute

snip more Jute sockpuppet bull****

Lest we forget, the Magnaquest fiasco took place in 1998, so of course
that 'report' would have the same date. It is of course just another
one of Jute's many fictional creations.

Don't believe it? Look up Jute on any literary website. He writes
*fiction* under the name 'Andrew McCoy'. If that's not enough for you,
Jute is not his surname. His *real* name is Andre Jute McCoy, a Sarth
Efrikaan of extremely dubious history, and we're all well aware of his
despicable (lack of) character.

--

Stewart Pinkerton | Music is Art - Audio is Engineering

On Tue, 03 May 2005 01:28:58 -0500, DougC
wrote:

wrote:

If you want to believe the lies Creepy Mike LaFever of Magnequest tells
you, Toad, I'm sure they'll make you feel better. In fact, if it will
make you feel better, I will confess to not existing either. I am an
artifact of my art teacher's mind with additional dialogue by my
favourite English teacher. Meanwhile, here is Bill May's report again.
It carries the date of first publication in the copyright notice at the
bottom. -- Andre Jute

(-I am loathe to get involved, but I just gotta say-)
----I don't know who Mike LaFever is,

Mike LeFevre of Magnaquest. It's just another one of Jute's childish
namecallings.

but I do know how to use Google.
There is only one return on the search result "bill may real mccoy
amplifiers", at http://www.diyparadiso.com/lundahl/shoot1.htm . There
are no other hits of any significance for " 'bill may' amplifiers", none
for " 'william may' amplifiers", none for "real mccoy amplifiers", or
for any combination of the independent terms "bill william may real
mccoy amplifiers", or even the name "real mccoy" in connection with any
sort of audio business.

Since you can find search results on just about any other company that
ever existed, I'd agree this is a spoof. The GoogleMatrix p0\/\/\nZ you!

Knowing that Jute's full name is Andre Jute McCoy might perhaps offer
a clue.....................

Also, he writes potboiler thrillers under the name 'Andrew McCoy', so
it's reasonable to conclude that the 'Bill May Report' is also
fictional.
--

Stewart Pinkerton | Music is Art - Audio is Engineering

TEST RATINGS OF 13 OUTPUT TRANSFORMERS

Rating Measurements Sighted Blind
1 Tango 1 Tango 1 Lundahl 3
2 Lundahl 3 Tango 2 Nature Sound 1
3 Tamura 1 Tamura 1 Tango 2
4 Nature Sound 1 Nature Sound 1 Tamura 1
5 Nature Sound 2 Magnequest 1 Tango 1
6 Tamura 2 Nature Sound 2 Nature Sound 2
7 Tango 2 Lundahl 3 Audio Note UK 4
8 Magnequest 1 Tamura 2 Tamura 2
9 Audio Note UK 4 Audio Note UK4 Russian 4
10 Magnequest 2 Magnequest 2 Magnequest 1
11 Tango 3 Tango 3 Tango 3
12 Chinese 5 Russian 4 Chinese 5
13 Russian 4 Chinese 5 Magnequest 2



Incidentally, after examining our results the Japanese manufacturer
chose the mid-price Tango for sonic, marketing and financial reasons.


I would have went with the "Lundahl 3" as the blind tests
say it's the best one and is mid priced. I'm not sure
what "industrial" appearance looks like, but I prefer my
tube amp tubes and the rest to be inside of metal boxes
so physical appearance beyond safety and build quality is
of little concern.

robert casey wrote:

TEST RATINGS OF 13 OUTPUT TRANSFORMERS

Rating Measurements Sighted Blind
1 Tango 1 Tango 1 Lundahl 3
2 Lundahl 3 Tango 2 Nature Sound 1
3 Tamura 1 Tamura 1 Tango 2
4 Nature Sound 1 Nature Sound 1 Tamura 1
5 Nature Sound 2 Magnequest 1 Tango 1
6 Tamura 2 Nature Sound 2 Nature Sound 2
7 Tango 2 Lundahl 3 Audio Note UK 4
8 Magnequest 1 Tamura 2 Tamura 2
9 Audio Note UK 4 Audio Note UK4 Russian 4
10 Magnequest 2 Magnequest 2 Magnequest 1
11 Tango 3 Tango 3 Tango 3
12 Chinese 5 Russian 4 Chinese 5
13 Russian 4 Chinese 5 Magnequest 2



Incidentally, after examining our results the Japanese manufacturer
chose the mid-price Tango for sonic, marketing and financial
reasons.


I would have went with the "Lundahl 3" as the blind tests
say it's the best one and is mid priced. I'm not sure
what "industrial" appearance looks like, but I prefer my
tube amp tubes and the rest to be inside of metal boxes
so physical appearance beyond safety and build quality is
of little concern.

You got it, Robert. But niche market tube amp design is not necessarily
directed entirely by electronic rationality. This Japanese
manufacturer's first idea was an amp around Magnequest transformers
because they were rare and "made in America". After Bill's tests he
changed his mind. I wanted the Lundahl as the obvious logical choice
but this Japanese amp maker didn't want a) Swedish transformers and b)
transformers under the deck. His wife, who does his accounts, told me
the midprice Tangos were chosen because they wanted "the money visible
on the deck" but they feared the top Tango would make the price so high
nobody would buy the amp. Many years later they are still in business,
so they must know their business.

Andre Jute