[Ian Bell[_2_]]

Eeyore wrote:

Ian Bell wrote:

Eeyore wrote:
Ian Bell wrote:
Eeyore wrote:
Patrick Turner wrote:
Eeyore wrote:
I'd simply rather not have the problem at all.
Fine, you don't like vacuum tubes or transformers it seems. Some people
at r.a.t have opposite views.
Tubes are fine for adding colouration.
So are transistors anly more so ;-)
I can design transistor circuits that will outperform the world's best audio
test equipment ( Audio Precision ). You can't do that with tubes.

Which of course means only they beat the test equipment. Does not mean
they sound any good.

It does sound good. Excellent in fact.


That's a subjective judgement and at the end of the day that's all that
counts, no matter what the measurements say.

Cheers

Ian
Graham

[Ian Bell[_2_]]

Eeyore wrote:

Patrick Turner wrote:

Eeyore wrote:
Patrick Turner wrote:
Eeyore wrote:
I'd simply rather not have the problem at all.
Fine, you don't like vacuum tubes or transformers it seems. Some people
at r.a.t have opposite views.
Tubes are fine for adding colouration.
Only if you want to add colouration by allowing THD/IMD to be too high.

That's what they're normally used for in the studio. Why else throw away watts
of power that has to be removed by expensive air conditioning ?


But long ago the level of "coloring" artifacts were measured and
quantified for their threshold of audibility. It is extremely easy to
ensure tube gear produces artifacts which remain far below audibility.

The standards then were rather different.


I am not here to try to convert you, but I have no trouble avoiding
problematic audio transformers.

This means I have never used input or IST coupling, but well made output
transformers are actually quite OK.
Matching and isolation / balancing OPTs on signal level professional
gear is routinely done.
Not any more it isn't. No need and wayyyyy too expensive.
The makers of expensive line level coupling transformers do a fine
amount of business.

A very small amount of business compared to the sales of pro and semi-pro gear.

Possibly, but those same companies make even more money making
transformers for pro gear as well you know.

Cheers

ian

Graham

[Eeyore]

Ian Bell wrote:

Eeyore wrote:
Ian Bell wrote:
Eeyore wrote:
Ian Bell wrote:
Eeyore wrote:
Patrick Turner wrote:
Eeyore wrote:
I'd simply rather not have the problem at all.
Fine, you don't like vacuum tubes or transformers it seems. Some people
at r.a.t have opposite views.
Tubes are fine for adding colouration.
So are transistors anly more so ;-)
I can design transistor circuits that will outperform the world's best audio
test equipment ( Audio Precision ). You can't do that with tubes.

Which of course means only they beat the test equipment. Does not mean
they sound any good.

It does sound good. Excellent in fact.

That's a subjective judgement and at the end of the day that's all that
counts, no matter what the measurements say.

In my long career in sound engineering I have always found that equipment that
measures better sounds better as long as you know how to interpret the readings
meaningfully.

Graham

[Eeyore]

dave wrote:

Eeyore wrote:

The makers of expensive line level coupling transformers do a fine
amount of business.

A very small amount of business compared to the sales of pro and semi-pro gear.

Graham

We have several hundred Cinemag transformers. They are very clean.

http://www.cinemag.biz/

They may well be. You don't have millions though. Personally, I've found Lundahl to
be the most accurate if you HAVE to use a transformer.

Graham

[Eeyore]

Ian Bell wrote:

Eeyore wrote:
Patrick Turner wrote:
Eeyore wrote:
Patrick Turner wrote:
Eeyore wrote:
I'd simply rather not have the problem at all.
Fine, you don't like vacuum tubes or transformers it seems. Some people
at r.a.t have opposite views.
Tubes are fine for adding colouration.
Only if you want to add colouration by allowing THD/IMD to be too high.

That's what they're normally used for in the studio. Why else throw away watts
of power that has to be removed by expensive air conditioning ?

But long ago the level of "coloring" artifacts were measured and
quantified for their threshold of audibility. It is extremely easy to
ensure tube gear produces artifacts which remain far below audibility.

The standards then were rather different.

I am not here to try to convert you, but I have no trouble avoiding
problematic audio transformers.

This means I have never used input or IST coupling, but well made output
transformers are actually quite OK.
Matching and isolation / balancing OPTs on signal level professional
gear is routinely done.
Not any more it isn't. No need and wayyyyy too expensive.
The makers of expensive line level coupling transformers do a fine
amount of business.

A very small amount of business compared to the sales of pro and semi-pro gear.

Possibly, but those same companies make even more money making
transformers for pro gear as well you know.

No, I don't know what you're getting at. Please explain.

Graham

[Ian Bell[_2_]]

Eeyore wrote:

Ian Bell wrote:

Eeyore wrote:
Ian Bell wrote:
Eeyore wrote:
Ian Bell wrote:
Eeyore wrote:
Patrick Turner wrote:
Eeyore wrote:
I'd simply rather not have the problem at all.
Fine, you don't like vacuum tubes or transformers it seems. Some people
at r.a.t have opposite views.
Tubes are fine for adding colouration.
So are transistors anly more so ;-)
I can design transistor circuits that will outperform the world's best audio
test equipment ( Audio Precision ). You can't do that with tubes.

Which of course means only they beat the test equipment. Does not mean
they sound any good.
It does sound good. Excellent in fact.
That's a subjective judgement and at the end of the day that's all that
counts, no matter what the measurements say.

In my long career in sound engineering I have always found that equipment that
measures better sounds better as long as you know how to interpret the readings
meaningfully.

Graham



In my very long career in sound engineering I have found that there is
some equipment that measures great but sounds crap and vice versa.


Cheers

Ian

[Ian Bell[_2_]]

Eeyore wrote:

Ian Bell wrote:

Eeyore wrote:
Patrick Turner wrote:
Eeyore wrote:
Patrick Turner wrote:
Eeyore wrote:
I'd simply rather not have the problem at all.
Fine, you don't like vacuum tubes or transformers it seems. Some people
at r.a.t have opposite views.
Tubes are fine for adding colouration.
Only if you want to add colouration by allowing THD/IMD to be too high.
That's what they're normally used for in the studio. Why else throw away watts
of power that has to be removed by expensive air conditioning ?

But long ago the level of "coloring" artifacts were measured and
quantified for their threshold of audibility. It is extremely easy to
ensure tube gear produces artifacts which remain far below audibility.
The standards then were rather different.

I am not here to try to convert you, but I have no trouble avoiding
problematic audio transformers.

This means I have never used input or IST coupling, but well made output
transformers are actually quite OK.
Matching and isolation / balancing OPTs on signal level professional
gear is routinely done.
Not any more it isn't. No need and wayyyyy too expensive.
The makers of expensive line level coupling transformers do a fine
amount of business.
A very small amount of business compared to the sales of pro and semi-pro gear.
Possibly, but those same companies make even more money making
transformers for pro gear as well you know.

No, I don't know what you're getting at. Please explain.

Graham


The op mentioned the business done by makers of expensive line level
transformers

You said that's small compared to the sales of pro and semi-pro gear

I meant, those same transformer manufacturers also make other types of
transformers for pro gear e.g. mic trannies, in significantly greater
quantities.

What I am saying is transformers are still used in a lot of pro gear.

Cheers

Ian

[Eeyore]

Ian Bell wrote:

What I am saying is transformers are still used in a lot of pro gear.

Remarkably few actually. Aside from power transformers. I don't know where you get your
ideas from.

Graham

[Hp]

Now about: MDI = microdécharges d' interface

The thing about the plastic is very strange one,

The general information about the problem research I have to ask a friend
again...

the origin is in french to search: "Pierre Johannet MDI = microdécharges d'
interface"

There are some english link....

http://www.ocellia.com/Anglais/a-mdi.html

http://www.6moons.com/audioreviews/ocellia2/cables.html

HpW

[Dave]

Eeyore wrote:

dave wrote:

Eeyore wrote:

The makers of expensive line level coupling transformers do a fine
amount of business.
A very small amount of business compared to the sales of pro and semi-pro gear.

Graham

We have several hundred Cinemag transformers. They are very clean.

http://www.cinemag.biz/

They may well be. You don't have millions though. Personally, I've found Lundahl to
be the most accurate if you HAVE to use a transformer.

Graham


Millions of what?

Some of the biggest events on earth are fed through Cinemag
transformers. Sweden is way to far away for custom fabrication.

[Patrick Turner]

dave wrote:

Eeyore wrote:

dave wrote:

Eeyore wrote:

The makers of expensive line level coupling transformers do a fine
amount of business.
A very small amount of business compared to the sales of pro and semi-pro gear.

Graham

We have several hundred Cinemag transformers. They are very clean.

http://www.cinemag.biz/

They may well be. You don't have millions though. Personally, I've found Lundahl to
be the most accurate if you HAVE to use a transformer.

Graham


Millions of what?

Some of the biggest events on earth are fed through Cinemag
transformers. Sweden is way to far away for custom fabrication.

I quite liked the specs at http://cinemag.biz/line_input/CM-99115.pdf

The balanced pro out to consumer input is a nominal 0.75V to 0.25V
ratio, with the pri driven with 600 ohms source and sec loaded by 2.4k.
This means the primary load = 21k approx. You could also go from an SE
triode CF to a floating output at 1/3 CF voltage into some other gear
where hum might have been a problem. There are other types of
transformer but most are based around having a source R = 600ohms, and
load = 600 ohms.

I have never used such things because I have never had any need.

Patrick Turner.

[Eeyore]

Patrick Turner wrote:

dave wrote:
Eeyore wrote:
dave wrote:
Eeyore wrote:

The makers of expensive line level coupling transformers do a fine
amount of business.
A very small amount of business compared to the sales of pro and semi-pro gear.

Graham

We have several hundred Cinemag transformers. They are very clean.

http://www.cinemag.biz/

They may well be. You don't have millions though. Personally, I've found Lundahl to
be the most accurate if you HAVE to use a transformer.

Graham

Millions of what?

Transformers.


Some of the biggest events on earth are fed through Cinemag
transformers. Sweden is way to far away for custom fabrication.

I quite liked the specs at http://cinemag.biz/line_input/CM-99115.pdf

The balanced pro out to consumer input is a nominal 0.75V to 0.25V
ratio, with the pri driven with 600 ohms source and sec loaded by 2.4k.
This means the primary load = 21k approx. You could also go from an SE
triode CF to a floating output at 1/3 CF voltage into some other gear
where hum might have been a problem. There are other types of
transformer but most are based around having a source R = 600ohms, and
load = 600 ohms.

I have never used such things because I have never had any need.

Odd to find 600 ohm sources and 2k4 inputs !

Graham

[Patrick Turner]

Eeyore wrote:

Patrick Turner wrote:

dave wrote:
Eeyore wrote:
dave wrote:
Eeyore wrote:

The makers of expensive line level coupling transformers do a fine
amount of business.
A very small amount of business compared to the sales of pro and semi-pro gear.

Graham

We have several hundred Cinemag transformers. They are very clean.

http://www.cinemag.biz/

They may well be. You don't have millions though. Personally, I've found Lundahl to
be the most accurate if you HAVE to use a transformer.

Graham

Millions of what?

Transformers.

Some of the biggest events on earth are fed through Cinemag
transformers. Sweden is way to far away for custom fabrication.

I quite liked the specs at http://cinemag.biz/line_input/CM-99115.pdf

The balanced pro out to consumer input is a nominal 0.75V to 0.25V
ratio, with the pri driven with 600 ohms source and sec loaded by 2.4k.
This means the primary load = 21k approx. You could also go from an SE
triode CF to a floating output at 1/3 CF voltage into some other gear
where hum might have been a problem. There are other types of
transformer but most are based around having a source R = 600ohms, and
load = 600 ohms.

I have never used such things because I have never had any need.

Odd to find 600 ohm sources and 2k4 inputs !

From my limited knowledge of using input trannies, the 3:1 step DOWN
tranny between a 600 ohm pro source and some consumer component needs to
be loaded at the sec with 2k4 to get the shown response presumably
without any peaking at HF. But a 1:3 tranny has a Z ratio of 9:1, so
that a load of 2k4 is seen as 21k at the primary, and a very easy to
drive load. The source impedance of 600 ohms becomes 600/9 at the sec,
or 66 ohms. The 2k4 won't make much difference to noise. There would not
be many tube circuits where the Rin would normally be as low as 2k4 but
where tou ever had a grounded grid circuit then the cathode input
resistance = anode load / tube gain in parallel with cathode to 0V
resistance. I can't think of any such application need.

Its interesting that they say they use 80% nickel core material, and
presumably the remaining 20% is GOSS. If you have a wasteless core with
Afe = 12sq.mm, then the number of turns to get a primary inductance to
have a reactance of 600 ohms at 3.2Hz would not be huge.
I have visions of winding my own next time I might use one. But then
there is the shielding issue.

If one wants to have a proper floating balanced input winding and a 1:1
turn and Z ratio, then I would have thought a 10k:10k tranny would be
better.

http://www.stevens-billington.co.uk/line_input.htm

Here there are 1:1 trannies with recommended source R 1k, and sec loads
of 10k.

To use such a tranny after a DAC and to couple to an SE triode input
stage on a preamp would probably be OK as the DAC would have an opamp
output stage. In a KORA DAC I have here to repair there are what seem to
be opamps, then a tubed output stage with 6DJ8, with an anode follower
consisting of gain triode with A=30, and then CF triode with shunt FB
loop around the two triodes to make an anode follower with Rout 100
ohms. The 4mAdc of idle tube current would allow max Vo into 600ohms of
about 1.8Vrms. Distortion would not be optimally low but then 600 ohms
would never be the load; it will be 10k because of the 10k secondary
load on the tranny, and DAC can maybe only make 1.4Vrms max, so the tube
distortion will be extremely low.

The KORA I have makes 1.4mV of PS related buzz noise at its output but
adding transformers won't reduce the noise; I have yet to find out the
cause.

The use of input transformers as so far described does require a low
source resistance in front of the input. There are now very few tubed or
non tubed preamps or components with high Rout; all will have an oppamp
buffer or cathode follower.

Patrick Turner.









Graham