[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;
Courier 10pt should work)

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:

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

(c) 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.

[Jon Yaeger]

Our newer members should know that Bill May is one of Andre Jute's alter
egos or pseudonyms.

This is rehashed material.

Jon







in article
, Andre
Jute at wrote on 12/9/07 7:15 PM:

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;
Courier 10pt should work)

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:

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

(c) 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.

[Ian Thompson-Bell]

Andre Jute wrote:
THE BILL MAY REPORT

Buying the best output transformer

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

Seems the Lundahl is best value for money. No surprise there.

Ian

[Bob Woodward]

Andre Jute wrote:
THE BILL MAY REPORT

Buying the best output transformer



TEST RATINGS OF 13 OUTPUT TRANSFORMERS

Rat. 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


(c) 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.

When even Chinese transformers are listed.

How about:
Hammond, Amplimo ( van der Veen ), Heyboer, ae-europe, Sowter ?

Robert

[Peter Wieck]

On Dec 10, 8:43 am, Bob Woodward "Bob wrote:

When even Chinese transformers are listed.

How about:
Hammond, Amplimo ( van der Veen ), Heyboer, ae-europe, Sowter ?

You forget a few things:

a) Mr. May is only another facet of the multi-faceted Andre, not an
actual person living or dead.
b) This "study" (of dubious veracity if actually done) was created
only to slam Magnequest - not to convey valid data. And, of course,
there are no data nor links to it.
c) Note the date (1998). Andre was in his honeymoon period with
Lundahl and Lundahl was still hoping for designs from him.
d) Far too many quality transformer makers were excluded or neglected
to make the study either valid or applicable to the hobbyist. To a
specifier or equipment maker, it is laughable.

So, why would you even ask those (apt but irrelevant) questions?

Peter Wieck
Wyncote, PA

[Jon Yaeger]

in article , Ian Thompson-Bell at
wrote on 12/10/07 5:37 AM:

Andre Jute wrote:
THE BILL MAY REPORT

Buying the best output transformer

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

Seems the Lundahl is best value for money. No surprise there.

Ian


You bet. As Andre can tell you, they are even a better value when you don't
pay for them . . . .

[Iain Churches[_2_]]

"Ian Thompson-Bell" wrote in message
...
Andre Jute wrote:
THE BILL MAY REPORT

Buying the best output transformer

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

Seems the Lundahl is best value for money. No surprise there.


The best UK winders, Sowter, are conspicuous in their absence.
IME they match Lundahl in both quality and price.

Iain

[tubegarden]

On Dec 10, 7:34�am, "Iain Churches" wrote:
"Ian Thompson-Bell" wrote in message

...

Andre Jute wrote:
THE BILL MAY REPORT

Buying the best output transformer

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

Seems the Lundahl is best value for money. No surprise there.

The best UK winders, Sowter, are conspicuous in their absence.
IME they match Lundahl in both quality and price.

Iain

[tubegarden]

Hi RATs!

If you want some specs on old output transformers,

SEE: www.one-electron.com

Measurments were done in the early 1990's so new stuff ain't there.

Only Andre thinks we only use new stuff

Happy Ears!
Al

PS sorry for the void post, my keyboard has too many keys, some of
which i push by mistake 8^P

[Ian Thompson-Bell]

Jon Yaeger wrote:
in article , Ian Thompson-Bell at
wrote on 12/10/07 5:37 AM:

Andre Jute wrote:
THE BILL MAY REPORT

Buying the best output transformer

Should you choose on measurements, reputation or price? Bill May
explains how professionals evaluate transformers.
snip
Seems the Lundahl is best value for money. No surprise there.

Ian


You bet. As Andre can tell you, they are even a better value when you don't
pay for them . . . .


That's as may be, but on this side of the pond Lundahl and Sowter are
the two main and respected players. I am not surprised Lundahl was near
the top and I would not be surprised to find Sowter near them had they
been included.

Ian

Ian

[Ian Thompson-Bell]

Iain Churches wrote:
"Ian Thompson-Bell" wrote in message
...
Andre Jute wrote:
THE BILL MAY REPORT

Buying the best output transformer

Should you choose on measurements, reputation or price? Bill May
explains how professionals evaluate transformers.
snip
Seems the Lundahl is best value for money. No surprise there.


The best UK winders, Sowter, are conspicuous in their absence.
IME they match Lundahl in both quality and price.

Iain


I tend to agree. I am using Sowter input transformers in my current mic
pre design.

Cheers

Ina

[Andre Jute]

On Dec 10, 10:37 am, Ian Thompson-Bell
wrote:
Andre Jute wrote:
THE BILL MAY REPORT

Buying the best output transformer

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

Seems the Lundahl is best value for money. No surprise there.

Ian

Actually, back when the research was done, Lundahl was a big surprise
to many people. Why the American and other niche winders reacted so
revealingly to me was because I introduced Lundahl to what they
thought of as their captive markets. After I tried Lundahls, and found
them good, other opinion formers did too. By the time Lynn Olson and
Harvey Rosenberg joined the party, the exciting part of the bovver was
almost over: there was an American distributor for Lundahl and soon
one or more newsgroups, and it was all very mainstream. By then,
though I shall always use Lundahls on my 300B amps, I had discovered
custom toroids designed by Menno van der Veen (Amplimo and Plitron)
for really big transmitting tube single ended amps...

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

[Andre Jute]

On Dec 10, 2:34 pm, "Iain Churches" wrote:
"Ian Thompson-Bell" wrote in message

...

Andre Jute wrote:
THE BILL MAY REPORT

Buying the best output transformer

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

Seems the Lundahl is best value for money. No surprise there.

The best UK winders, Sowter, are conspicuous in their absence.
IME they match Lundahl in both quality and price.

Iain

You haven't read Bill's screed carefully enough, Iain. The evaluation
was a commercial job, which had to include several Japanese
transformers specified by the Japanese manufacturer paying for the
work. We just added a few extra transformers to the test because we
happened to have thirteen identical Real McCoy Type 33 amps available.

I have no problem with Sowter's quality or price; I just didn't have
any suitable transformers from them at the time, or I would have
included them.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

[Andre Jute]

On Dec 10, 3:56 pm, tubegarden wrote:
Hi RATs!

If you want some specs on old output transformers,

SEE:www.one-electron.com

Measurments were done in the early 1990's so new stuff ain't there.

Only Andre thinks we only use new stuff

Rubbish. I built some super amps with transformers that got left
behind in Ireland when the Berlin Airlift suddenly turned out to be
not necessary. In particular I remember the trannies for big
transmitting tubes, and some broadband chokes I wish I still had so
Patrick and I could reverse engineer them and get rich!


Happy Ears!
Al

PS sorry for the void post, my keyboard has too many keys, some of
which i push by mistake 8^P

As long as you still know it's name is "keyboard", don't worry if you
push the wrong buttons.

Andre Jute
Superchild

[Andre Jute]

On Dec 10, 1:43 pm, Bob Woodward "Bob wrote:
Andre Jute wrote:
THE BILL MAY REPORT

Buying the best output transformer

TEST RATINGS OF 13 OUTPUT TRANSFORMERS

Rat. 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

(c) 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.

When even Chinese transformers are listed.

How about:
Hammond, Amplimo ( van der Veen ), Heyboer, ae-europe, Sowter ?

Robert

The Chinese and Russian transformers were placebos, necessary for the
statistical respectability of the tests. You should read the
description of the test, not only the table. It tells you clearly no
universal or comprehensive result was even contemplated.

If you make a comprehensive test, in which you can include whichever
transformers you like, be sure to publish the results, and let us know
how much time and money it takes.

Andre Jute
Nah, the glass is always half full

[Jon Yaeger]

in article
, Andre
Jute at wrote on 12/10/07 9:10 PM:

On Dec 10, 2:34 pm, "Iain Churches" wrote:
"Ian Thompson-Bell" wrote in message

...

Andre Jute wrote:
THE BILL MAY REPORT

Buying the best output transformer

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

Seems the Lundahl is best value for money. No surprise there.

The best UK winders, Sowter, are conspicuous in their absence.
IME they match Lundahl in both quality and price.

Iain

You haven't read Bill's screed carefully enough, Iain. The evaluation
was a commercial job, which had to include several Japanese
transformers specified by the Japanese manufacturer paying for the
work. We just added a few extra transformers to the test because we
happened to have thirteen identical Real McCoy Type 33 amps available.

I have no problem with Sowter's quality or price; I just didn't have
any suitable transformers from them at the time, or I would have
included them.


Ya mean, you couldn't con them as easily as say, other folks?

[Jon Yaeger]

in article
, Andre
Jute at wrote on 12/10/07 9:23 PM:

On Dec 10, 1:43 pm, Bob Woodward "Bob wrote:
Andre Jute wrote:
THE BILL MAY REPORT

Buying the best output transformer

TEST RATINGS OF 13 OUTPUT TRANSFORMERS

Rat. 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

(c) 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.

When even Chinese transformers are listed.

How about:
Hammond, Amplimo ( van der Veen ), Heyboer, ae-europe, Sowter ?

Robert

The Chinese and Russian transformers were placebos, necessary for the
statistical respectability of the tests. You should read the
description of the test, not only the table. It tells you clearly no
universal or comprehensive result was even contemplated.

If you make a comprehensive test, in which you can include whichever
transformers you like, be sure to publish the results, and let us know
how much time and money it takes.

Andre Jute
Nah, the glass is always half full



'Dre,

You ought to be able to conduct some tests on, say, 10 Swedish-made
transformers at no additional cost to yourself, right?

What else do you have better to do with your time?

Me and the Missus, why, we like to go out and shoot squirrels and fry up
their brains. There's not much meat there, but it sure is tasty!!

Jon

[RdM]

Andre Jute in
:


Andre Jute
Nah, the glass is always half full


Whereas "The Engineer" would opine it was twice the necessary size?

[Mark S]

"Jon Yaeger" wrote in message
...
in article
, Andre
Jute at wrote on 12/10/07 9:23 PM:

On Dec 10, 1:43 pm, Bob Woodward "Bob wrote:
Andre Jute wrote:
THE BILL MAY REPORT

Buying the best output transformer

TEST RATINGS OF 13 OUTPUT TRANSFORMERS

Rat. 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

(c) 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.

When even Chinese transformers are listed.

How about:
Hammond, Amplimo ( van der Veen ), Heyboer, ae-europe, Sowter ?

Robert

The Chinese and Russian transformers were placebos, necessary for the
statistical respectability of the tests. You should read the
description of the test, not only the table. It tells you clearly no
universal or comprehensive result was even contemplated.

If you make a comprehensive test, in which you can include whichever
transformers you like, be sure to publish the results, and let us know
how much time and money it takes.

Andre Jute
Nah, the glass is always half full



'Dre,

You ought to be able to conduct some tests on, say, 10 Swedish-made
transformers at no additional cost to yourself, right?

What else do you have better to do with your time?

Me and the Missus, why, we like to go out and shoot squirrels and fry up
their brains. There's not much meat there, but it sure is tasty!!

Jon


Now I've heard of squirrel pie (northern redneck dish) but not fried
squirrel brains.
M
M

[Andre Jute]

On Dec 11, 9:44 am, RdM wrote:
Andre Jute in
:



Andre Jute
Nah, the glass is always half full

Whereas "The Engineer" would opine it was twice the necessary size?

LOL. Spot on. I can just hear Iain's pal Stinkerton pontificating on
how "those amateurs designed the glass twice the necessary size".

But I was remarking on people I never heard of coming here and
bitching that I left out their favourite transformers when they're
getting a summary of results on measurements, sighted and blind
listening tests, on 13 different transformers, more transformers than
most of them have ever seen or heard, research conducted with test
equipment and engineering, statistical and other skills they won't
master in a lifetime, and costing more than they will earn in several
years. Ask yourself who, besides me, you know who can simultaneously
put all the major Japanese transformer brands together in one room on
duplicate amplifiers -- and that's just a tiny, tiny part of a job
entirely beyond the imagination (and attention span) of these
kibbitzers. Negative clowns like that really make me wonder why I
bother to share anything.

Some people, accidentally seated at the Last Supper, even as they
partake of the sacramental bread and wine, will complain that the
party cannot ever be reconstituted with all the original diners.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

[Iain Churches[_2_]]

"Andre Jute" wrote in message
...
On Dec 11, 9:44 am, RdM wrote:
Andre Jute in
:



Andre Jute
Nah, the glass is always half full

Whereas "The Engineer" would opine it was twice the necessary size?

LOL. Spot on. I can just hear Iain's pal Stinkerton pontificating on
how "those amateurs designed the glass twice the necessary size".

My pal? LOL:-) I drank a glass of champagne with some colleagues
at Scandinavian Broadcast on the morning of June 2nd 2007 - the first
anniversary of Pinky's disappearance from RAT.

But your analogy of the half filled/half emptied glass is a good one.
It was explained by a main dealer in Saigon, ( who just a few
months ago) offered me any ten tube amps in his emporium for
USD 1 000) that the OPTs on amps built in the far East are
very small in physical size because they never need to deliver
their full power:-) He said to me, in a very serious tone,
"Do not pay for what you don't need!" Older and wiser:-)

This is in stark contrast to Sowter, Lundahl and some others
which can deliver full power continuously at say 50Hz


But I was remarking on people I never heard of coming here and
bitching that I left out their favourite transformers when they're
getting a summary of results on measurements, sighted and blind
listening tests, on 13 different transformers, more transformers than
most of them have ever seen or heard, research conducted with test
equipment and engineering, statistical and other skills they won't
master in a lifetime, and costing more than they will earn in several
years. Ask yourself who, besides me, you know who can simultaneously
put all the major Japanese transformer brands together in one room on
duplicate amplifiers

Indeed an interesting and most worthwhile experiment, which few if
any of us can claim to have bettered. It is just a pity that the company
whose transformers are considered by many to be the finest, was not
represented.

I have listened to identical monoblocs one with a
Sowter UO70 (6550/KT88 PP) and the other with a Hammond
1650P. No-one could fail to hear the difference between them,
even at very modest levels.


Regards to all
Iain

[Jon Yaeger]

'Dre,

You ought to be able to conduct some tests on, say, 10 Swedish-made
transformers at no additional cost to yourself, right?

What else do you have better to do with your time?

Me and the Missus, why, we like to go out and shoot squirrels and fry up
their brains. There's not much meat there, but it sure is tasty!!

Jon


Now I've heard of squirrel pie (northern redneck dish) but not fried
squirrel brains.
M
M


It's a delicacy in parts of Kentucky, Indiana, and West Virginia. Said to
be small like an acorn a lot of work to prepare . . .

A few years ago someone noticed a much higher-than-normal incidence of CJD
among the rustic denizens who consumed the tissue, even if fried.
Apparently, prions are responsible for the neuropathy.

Some prion-related diseases may take years to manifest.

Jon

[Andre Jute]

On Dec 12, 7:37 am, "Iain Churches" wrote:
"Andre Jute" wrote in message

...

On Dec 11, 9:44 am, RdM wrote:
Andre Jute in
:

Andre Jute
Nah, the glass is always half full

Whereas "The Engineer" would opine it was twice the necessary size?

LOL. Spot on. I can just hear Iain's pal Stinkerton pontificating on
how "those amateurs designed the glass twice the necessary size".

My pal? LOL:-) I drank a glass of champagne with some colleagues
at Scandinavian Broadcast on the morning of June 2nd 2007 - the first
anniversary of Pinky's disappearance from RAT.

But your analogy of the half filled/half emptied glass is a good one.
It was explained by a main dealer in Saigon, ( who just a few
months ago) offered me any ten tube amps in his emporium for
USD 1 000) that the OPTs on amps built in the far East are
very small in physical size because they never need to deliver
their full power:-)

That's a polite way of saying their supposed power rating is a lie.

He said to me, in a very serious tone,
"Do not pay for what you don't need!" Older and wiser:-)

This is in stark contrast to Sowter, Lundahl and some others
which can deliver full power continuously at say 50Hz

Menno van der Veen, considered by many the greatest living audio
transformer designer, is a quiet, charming Dutchman. But his voice
intensifies ever so slightly when he starts talking about full power
ratings. He also designs a meaty transformer.

But I was remarking on people I never heard of coming here and
bitching that I left out their favourite transformers when they're
getting a summary of results on measurements, sighted and blind
listening tests, on 13 different transformers, more transformers than
most of them have ever seen or heard, research conducted with test
equipment and engineering, statistical and other skills they won't
master in a lifetime, and costing more than they will earn in several
years. Ask yourself who, besides me, you know who can simultaneously
put all the major Japanese transformer brands together in one room on
duplicate amplifiers

Indeed an interesting and most worthwhile experiment, which few if
any of us can claim to have bettered. It is just a pity that the company
whose transformers are considered by many to be the finest, was not
represented.

Tango was fully represented in the test with three different price
ranges and qualities of Tango transformers being present. Herb
Reichert, who imported Tango to the US before he became the Audio Note
UK importer, was reported as saying I made the right choice. (Wasn't
my choice actually but that of a well-informed Japanese manufacturer.)

If, because you're British, you mean Sowter, back when the tests were
taken, several years before the Bill May report was published, Sowter
was just starting out in servicing the audiophile market; until then
they had been suppliers to broadcasters and OEM. In any event, I don't
think I can agree that Sowter transformers are better value than
Lundahl, among other reasons because the Lundahls are so versatile
because of their segmentation. When the sound is at that level
already, you start looking for ever small marks of distinction, of
course, which soon leaves only a matter of taste.

I have listened to identical monoblocs one with a
Sowter UO70 (6550/KT88 PP) and the other with a Hammond
1650P. No-one could fail to hear the difference between them,
even at very modest levels.

Sure. But did you check the prices? You're not comparing oranges with
oranges, Iain. Hammond are generally available off the shelf, they are
good value for money, and they deserve our support for that those two
factors alone. Furthermore, you just slot in a Hammond into any of a
gazillion standard designs. To order a Sowter, you actually need to
know what you're doing, though, on the other hand, Sowter have the
distinct advantage that Brian Sowter will help you choose the right
transformer from their list, or modify an existing design, or create
an entirely new design, all for no or very little extra cost.

If I were to make a comparison between one of my humongously expensive
Menno van der Veen custom designs, wound for me by Amplimo and
Plitron, and somebody else's off-the-shelf reasonably priced
transformer, say Sowter or Lundahl, you'd straight away say I was not
being fair. Though to a lesser extent, that is also true of a Hammond-
Sowter comparison.

Regards to all
Iain

There's an additional problem with these comparisons (and it isn't
that your other pal,
Arny Krueger, will shortly and spuriously condemn your test as sighted
-- make my day, Arny!). It is simple elitism. You and I and a few
others on RAT can probably afford anything we want (and Patrick, who
rattles onabout how poor he is, can wind whatever he wants), but not
everyone can. Someone who might have to save up for Hammond
transformers, or work with what can be scrounged out of scrap
receivers or old tube televisions (vertical transformers are brilliant
low power SE output trx), might consider this entire conversation
beside the point: he doesn't want to know that the Sowter sounded
superior to your very expensively trained ears, he wants to know how
good the Hammonds sound when they aren't being monstered by some
elitist's minority choice and overwhelming professional
discrimination. The answer is probably, very nice indeed; the Hammonds
I have heard sounded like good value for the money. That is a truth
that we bring don't bring out often enough.

I'm not knocking, you understand; I am as guilty as everyone else. I
am just making the case that there are levels of output transformers,
as there are levels of everything else.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

[Iain Churches[_2_]]

"Andre Jute" wrote in message
...
On Dec 12, 7:37 am, "Iain Churches" wrote:
"Andre Jute" wrote in message

...


Iain wrote:

But your analogy of the half filled/half emptied glass is a good one.
It was explained by a main dealer in Saigon, ( who just a few
months ago) offered me any ten tube amps in his emporium for
USD 1 000) that the OPTs on amps built in the far East are
very small in physical size because they never need to deliver
their full power:-)

That's a polite way of saying their supposed power rating is a lie.

Yes. That was my interpretation. But of course, there is an
element of truth in this - even though it is no justification for skimping
on the specification. In a domestic listening session, the amp
may never even approach peak power.


Indeed an interesting and most worthwhile experiment, which few if
any of us can claim to have bettered. It is just a pity that the company
whose transformers are considered by many to be the finest, was not
represented.

If, because you're British, you mean Sowter, back when the tests were
taken, several years before the Bill May report was published, Sowter
was just starting out in servicing the audiophile market; until then
they had been suppliers to broadcasters and OEM.

It is true that Sowter were contractors to the BBC, and also the major
studios, but they also had strong hi-fi sales. My Dad was buying Sowter
transformers for his hi-fi projects when I was just a slip of a lad.

I have listened to identical monoblocs one with a
Sowter UO70 (6550/KT88 PP) and the other with a Hammond
1650P. No-one could fail to hear the difference between them,
even at very modest levels.

Sure. But did you check the prices? You're not comparing oranges with
oranges, Iain. Hammond are generally available off the shelf, they are
good value for money, and they deserve our support for that those two
factors alone.

Agreed. It is a good thing that we have have price/quality options,
but IMO the OPT is the very 'last* place to save money.

Many years ago, I struggled with a Williamson project, that had an
OPT bought in the Tottenham Court Rd, in London, which in those days
was full of hi-fi and component shops. The amp was not an amp but an
oscillator. I never did get it to work properly, but realised a lot later
having build the same circuit with a Drake transformer, that the first
(very cheap) transformer was the reason for my failure.

If I were to make a comparison between one of my humongously expensive
Menno van der Veen custom designs, wound for me by Amplimo and
Plitron, and somebody else's off-the-shelf reasonably priced
transformer, say Sowter or Lundahl, you'd straight away say I was not
being fair.

That would be an interesting comparison if it could be set up.

There's an additional problem with these comparisons (and it isn't
that your other pal, Arny Krueger, will shortly and spuriously
condemn your test as sighted
-- make my day, Arny!). It is simple elitism.

Not much to see when the OPTs are covered by a cage. But
maybe the superior nickel plating on the Sowter catches the sunlight
better through the ventilation slots. That *must* make for a better
listening experience:-)))

You and I and a few
others on RAT can probably afford anything we want (and Patrick, who
rattles onabout how poor he is, can wind whatever he wants), but not
everyone can. Someone who might have to save up for Hammond
transformers, or work with what can be scrounged out of scrap
receivers or old tube televisions (vertical transformers are brilliant
low power SE output trx), might consider this entire conversation
beside the point: he doesn't want to know that the Sowter sounded
superior to your very expensively trained ears, he wants to know how
good the Hammonds sound when they aren't being monstered by some
elitist's minority choice and overwhelming professional
discrimination. The answer is probably, very nice indeed; the Hammonds
I have heard sounded like good value for the money. That is a truth
that we bring don't bring out often enough.

They are indeed good value, but we were discussing purchase of
the best OPT. Hammond are not at the top of the table. Compare
them with, for example the German manufacturer, Welter. They are in
about the same price range.

There are in fact a number of small companies still making audio
transformers of good quality at very reasonable prices.

Take a look at:

http://www.welter-electronic.de/baut...afos/trafo.htm


I'm not knocking, you understand; I am as guilty as everyone else. I
am just making the case that there are levels of output transformers,
as there are levels of everything else.

Yes indeed. I agree that transformer must be chosen to suit the
project, and its budget. I justify the spending of a large proportion
of the budget on the OPT by the fact that this amp will be
a thing of musical joy for the next 30 years (if not to me, then hopefully
to someone else!) So, if I spend say USD 300 on an output transformer,
that equates to USD 10/year, or less than 28 cents/day. That doesn't
sound too bad now, does it? :-)

Regards to all

Iain

[John Byrns]

In article i,
"Iain Churches" wrote:

"Andre Jute" wrote in message
...
On Dec 12, 7:37 am, "Iain Churches" wrote:
"Andre Jute" wrote in message

...


Iain wrote:

But your analogy of the half filled/half emptied glass is a good one.
It was explained by a main dealer in Saigon, ( who just a few
months ago) offered me any ten tube amps in his emporium for
USD 1 000) that the OPTs on amps built in the far East are
very small in physical size because they never need to deliver
their full power:-)

That's a polite way of saying their supposed power rating is a lie.

Yes. That was my interpretation. But of course, there is an
element of truth in this - even though it is no justification for skimping
on the specification. In a domestic listening session, the amp
may never even approach peak power.

An OPT small in physical size doesn't necessarily imply a limited peak
power output, it only implies a reduced maximum power output at the
lowest frequencies.

When high power output at very low frequencies is not needed for proper
reproduction of the desired program, it is sometimes nice to have a
smaller more compact OPT, although I suppose there is an advantage to
large visual size when selling to audiophiles. What is the lowest
frequency produced by each of the various types/styles of music?


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

[Andre Jute]

Iain Churches:
But your analogy of the half filled/half emptied glass is a good one.
It was explained by a main dealer in Saigon, ( who just a few
months ago) offered me any ten tube amps in his emporium for
USD 1 000) that the OPTs on amps built in the far East are
very small in physical size because they never need to deliver
their full power:-)

Andre Jute:
That's a polite way of saying their supposed power rating is a lie.

Iain:
Yes. That was my interpretation. But of course, there is an
element of truth in this - even though it is no justification for skimping
on the specification. In a domestic listening session, the amp
may never even approach peak power.

John Byrns:
An OPT small in physical size doesn't necessarily imply a limited peak
power output, it only implies a reduced maximum power output at the
lowest frequencies.

And
That's a good reason to include in the transformer specification, as
the better winders do, the halfpower frequency.

John:
When high power output at very low frequencies is not needed for proper
reproduction of the desired program, it is sometimes nice to have a
smaller more compact OPT, although I suppose there is an advantage to
large visual size when selling to audiophiles.

And
It isn't just audiophiles. Musical expectations have moved on. The
Magnequest "Peerless" TFA-204 is claimed (by Creepy Mike LaFevre,
hardly an unimpeached witness) to be an exact copy of the replacement
output transformer for the iconic WE91 SE300B amp. I made all the
points necessary about this wretched little transformer when I
published in Glass Audio Vol 9 No 6 1997 on p60 a photograph of the
Magnequest "Peerless" TFA204 next to a Lundahl LL1623-SE 90mA. The
Lundahl, at that time just about to become the reference output for
300B and suchlike, made the TFA204 look like a matchbox. The TFA204
with its miserable sub-6 Henry primary impedance was never in the
game. In addition, you need the size to get the current. The poor
little thing Creepy Mike sold was never capable of the claimed 60mA. I
know. I had a pair, of which one didn't fall apart in the post and was
thus available for tests. After trying 60mA -- nasty -- I binned them
as rubbish. But that I threw them out wasn't just due to Creepy Mike's
Magnequest Art i.e. shoddy construction but to the fact that even if
the TFA-204 could pass 60mA as claimed in the spec without saturating,
they were useless for modern applications. You will remember that you
and I humiliated Mike LaFever and his nasty little friend BobC
Chernofsky in a design contest; one reason was that they ignorantly
chose a traditional cookbook set of operating parameters (that is, low
current) straight off the WE spec sheet without asking whether it was
suitable for audio work.

John:
What is the lowest
frequency produced by each of the various types/styles of music?

And
In recorded music what you get on the CD depends not on the music at
all but on what producers think the public expects. On the specifics
I'll let Iain answer; after all, his professional colleagues did it to
us.

And
However, there is a related question raised by your remark, already
bothersome to Olson before the war and to Gilbert Briggs immediately
after the war. This is the harmonic analysis of the amount of energy
in a wave, which has implications for how the human ear puts together
reproduced music. Consider a single violin note of 196c/s. In has
harmonics at 392, 588, 784c/s, and so on, say perceptibly down to the
19th, which is still 2.6dB above the fundamental. That comes about
because the actual 196c/s note, the fundamental, represents only 0.1
per cent of the energy of the note. The second harmonic represents 26%
or 24.2dB, the third 45.2% or 26.6dB, the fourth 8.8% or 19.5dB, the
fifth near enough the same, the sixth and the eighth around 4.5% or
16.5dB, while the seventh falls to 0.1% or 1.3dB. The other
significant harmonics are the 13, at the same level as the 19th, and
the 17th at 1.1% and 10.4dB. (Adapted from Seasho Psychology of
Music, McGraw-Hill.)

And
Those numbers explain why we are perfectly happy with speakers that
are 6dB down at 45Hz: there is very little to hear below that! But we
hear it all the same, because the ear reconstitutes the fundamental
from the harmonics.

And
While full power for the entire audio band might be overkill, I do
think that a stiff halfpower frequency spec is not an unreasonable
expectation. But it will certainly correlate very closely with the
mass (size, weight) of the transformer.

Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

HTH.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

[Mark S]

snip for brevity


I have listened to identical monoblocs one with a
Sowter UO70 (6550/KT88 PP) and the other with a Hammond
1650P. No-one could fail to hear the difference between them,
even at very modest levels.


Regards to all
Iain


Hi Iain,
Curious about the vintage of 1650P iron, they were redesigned years ago say
early-mid 90's. If I could afford a set of 070's I would buy them tomorrow
but the exchange rate as it is and the "carriage"...oh well.
Best Regards,
Mark

[RdM]

"Iain Churches" wrote in
.saunalahti.fi:

I have listened to identical monoblocs one with a
Sowter UO70 (6550/KT88 PP) and the other with a Hammond
1650P. No-one could fail to hear the difference between them,
even at very modest levels.

The Hammond 1650P is a 60W, 6,600a-a, 200mA max OPT with two sec windings that
are only all engaged when set for 8, not 4 & 16. It weighs 8lb, or ~3.628kg,
and like nearly all of that range are spec'd 30 Hz. to 30 Khz. at full rated
power (+/- 1 db max. - ref. 1 Khz) minimum. See it in the range at
http://www.hammondmfg.com/1608.htm

The Sowter UO70 is a 100W, 4500a-a, 200mA max OPT with 4 sec windings that are
always engaged, has a "shipping weight" of 7kg. Freq specs listed differently:
http://www.sowter.co.uk/specs/u070.htm

So they *are* rather different ...

Now, if you had compared the 1650P with the 50W, 6.6k 150ma Sowter UO89 ...
http://www.sowter.co.uk/specs/u069.htm

or, the Sowter UO70 with ... say ... the nearest woud be 1650R, 100W, 5k,
318ma, 12lb or ~5.44kg, then you might have had more reasonable comparisons!

As it is, the "identical monoblocs" may have been suited more to either
impedance let alone the other differences. What was the circuit set for?

I'm not surprised at an audible difference!
Apples to pears ... USA to UK ?

However, I'm interested, in that I have a pair of the 1650R above, which will
eventually find their way into a project. Fred Nachbaur spoke well of them in
Dogzilla, albeit it being ostensibly not a hi-fi amp as such. We'll see ...

Regards to all
Iain

Ah, I see including Stewart P after all!!
Nice to see. Perhaps it's the season? ;=})
Best wishes!!!
--
Regards to all;-

Ross Matheson
--
[PS: I can see I have other writings to catch up on;- so little time!;-]

[Iain Churches[_2_]]

"Mark S" wrote in message
...
snip for brevity


I have listened to identical monoblocs one with a
Sowter UO70 (6550/KT88 PP) and the other with a Hammond
1650P. No-one could fail to hear the difference between them,
even at very modest levels.


Regards to all
Iain


Hi Iain,
Curious about the vintage of 1650P iron, they were redesigned years ago
say early-mid 90's. If I could afford a set of 070's I would buy them
tomorrow but the exchange rate as it is and the "carriage"...oh well.
Best Regards,
Mark

Hi Mark. The comparison was made not more than two years ago,
just before I moved to my current workshop.

The U070 is a splendid transformer. I have a pair of these potted
sitting on the shelf waiting for a KT88 project I have bubbling.

Regarding the exchange rates. Both sterling and the Euro are strong.
Your policy-makers in the US have much to answer for:-(

Iain

[RdM]

John Byrns in
:

An OPT small in physical size doesn't necessarily imply a limited peak
power output, it only implies a reduced maximum power output at the
lowest frequencies.

Not only at all; one might (with recourse to a catalogue) infer some nickel.

When high power output at very low frequencies is not needed for proper
reproduction of the desired program, it is sometimes nice to have a
smaller more compact OPT, although I suppose there is an advantage to
large visual size when selling to audiophiles.

What utter waffle! I mean, nice padding!

What is the lowest
frequency produced by each of the various types/styles of music?

42 was the basic answer once ...

The info is out there for the non-musical people who do not know already ...

But infra bass could be infra dig!

There's a note about infrasonic frequencies buried deep in Enya's 'Watermark'
in discussions on the Graham Holliman Velocity Coupled Infra Bass Speaker,
here http://tinyurl.com/ypu7qk and beyond.

Regards,

John Byrns

Yeah,

Ross Matheson
tangent

[Iain Churches[_2_]]

As it is, the "identical monoblocs" may have been suited more to either
impedance let alone the other differences. What was the circuit set for?

They had a B+ of 550V, so about 55W into 8 Ohms.(B+W 801D
loudspeakers)

I'm not surprised at an audible difference!
Apples to pears ... USA to UK ?

These were Swedish people listening. They usually hold
neither the British nor the Americans in very high regard:-))
One wonders if they would have picked a Lundahl if one
had been fitted.

But there is definately a difference in expectation from country
to country. One comes across this also in recording with
preferences in playing styles and sounds. A very good jazz
saxophonist of my aquaintance talks about his
"Long Island sound" He is a Dane from Copenhagen!

Ah, I see including Stewart P after all!!
Nice to see. Perhaps it's the season? ;=})

Gone but not forgotten:-)

regards to all
Iain

[Iain Churches[_2_]]

"John Byrns" wrote in message
...
In article i,
"Iain Churches" wrote:

An OPT small in physical size doesn't necessarily imply a limited peak
power output, it only implies a reduced maximum power output at the
lowest frequencies.

Yes indeed, and results in a drastic increase in LF distortion.

When high power output at very low frequencies is not needed for proper
reproduction of the desired program, it is sometimes nice to have a
smaller more compact OPT, although I suppose there is an advantage to
large visual size when selling to audiophiles. What is the lowest
frequency produced by each of the various types/styles of music?

In classical music there is little below 40 Hz and nothing below 27Hz
(except of course the occasional organ pedal note) The lowest note
being the bottom strings of the orchestral harp, C1 at approx 33Hz.
There are concert grand pianos, example Bechstein, that have an
extended keyboard down to F at 22Hz, or sometimes lower,
but the standard 88 note piano keyboard has Ao at 27Hz,

In popular music, the four string bass guitar is normally tuned E-A-D-G
so the lowest note is about 41 Hz. There is a five string bass guitar
usually tuned B-E-A-D-G so here the lowest note B1 is about 31 Hz.
These figs are just to illustrate the point. I use the words "about" and
"approx" so don't pick me up on decimal points:-)

In most broadcast and studios back in the tube amp era,
expected power bandwidth for amplifiers was 20Hz to say 35kHz.
All the Sowter, Radford and Lundahl transformers that I have
ever used meet this requirement - some are considerably better.

Best regards
Iain

[RdM]

Iain Churches wrote

But there is definately a difference in expectation from country
to country. One comes across this also in recording with
preferences in playing styles and sounds.

That's half-way towards "defiantly" ;- but I agree in my experience

[Mark S]

"Iain Churches" wrote in message
i.fi...

"Mark S" wrote in message
...
snip for brevity


I have listened to identical monoblocs one with a
Sowter UO70 (6550/KT88 PP) and the other with a Hammond
1650P. No-one could fail to hear the difference between them,
even at very modest levels.


Regards to all
Iain


Hi Iain,
Curious about the vintage of 1650P iron, they were redesigned years ago
say early-mid 90's. If I could afford a set of 070's I would buy them
tomorrow but the exchange rate as it is and the "carriage"...oh well.
Best Regards,
Mark

Hi Mark. The comparison was made not more than two years ago,
just before I moved to my current workshop.

The U070 is a splendid transformer. I have a pair of these potted
sitting on the shelf waiting for a KT88 project I have bubbling.

I have the 1650R's that date prior to Hammonds redesign, these are much
larger than the current offering 1650R; they actually weigh 12 lbs as the
Hammond data sheet continues to list. The old designs also used 20% UL taps
vs 40% now.


Regarding the exchange rates. Both sterling and the Euro are strong.
Your policy-makers in the US have much to answer for:-(

Iain

Well, as I manufacture quite alot for Eurpoe these days, it has a benefit as
well, my companies sales to europe are through the roof.

Regards,
Mark

[Iain Churches[_2_]]

"RdM" wrote in message
...
Iain Churches wrote

But there is definately a difference in expectation from country
to country. One comes across this also in recording with
preferences in playing styles and sounds.

That's half-way towards "defiantly" ;- but I agree in my experience

You are "definitely" correct:-)) This subject of
territorial preferences in music and also sound
production is an interesting one.

I remember the sudden rise in popularity of the
HiWatt amplifier on recording sessions UK studios.
(Pete Townsend used Hi Watt)

Similarly on the question of playing styles, many
students used to practice the recorded solos and
hot lucks of their idols ( I don't know of a single
jazz saxophone player of any merit who, as a
student has not struggled to learn Charlie Parker's
"Koko", or the embouchure to create the unique
sound of Earl Bostic "Flamingo" the track from
which the legendary John Coltrane is said to have
developed his own style.

It's not about emulation but about simulation in the
process of finding your own style and sound. I have
adopted the same course as a recording engineer.
Look, listen and learn. Everyone can teach you
something, even if it is simply *not* how to do it!

Regards to all
Iain