Вот что они сами пишут в истории Tannoy:
ANISOTROPIC BARIUM FERRITE
From 1947 to 1978 Tannoy Dual Concentric drivers used a metal magnet made from an alloy of nickel,
aluminium, cobalt and iron. Although of great strength this magnet material was not very efficient in
power to weight ratio and difficulty in the world supply of cobalt was generating a problem in
maintaining smooth production at the Tannoy factories in West Norwood, London and Coatbridge in
Scotland.
During the latter part of 1977 the decision was taken by Tannoy to design a new series of Dual
Concentric drive units using Anisotropic Barium Ferrite magnets. This material is more efficient in
power to weight ratio and had a much higher coercive force leading to fewer problems in
demagnetization under high power or low storage temperatures.
New magnet charging equipment was purchased to supply the much higher magnetizing force needed by the
new material. Magnets are supplied unmagnetized to Tannoy so that the magnet can be magnetized with
all its metal pole pieces in place for higher gap field strength. The process of magnetization is
called 'charging' the magnet and takes place inside a heavy coil that generates an exceptionally
strong magnetic field for a faction of a second to align the magnetic domains within the material.
The first unit to emerge with the Anisotropic Barium Ferrite magnet system was a very high power high
sensitivity midrange unit used in the Buckingham and Windsor cabinet models. This unit subsequently
went on to be used in the Buckingham Monitor and, with further modifications in high power music
concert rigs throughout Europe.
ANISOTROPIC BARIUM FERRITE
From 1947 to 1978 Tannoy Dual Concentric drivers used a metal magnet made from an alloy of nickel,
aluminium, cobalt and iron. Although of great strength this magnet material was not very efficient in
power to weight ratio and difficulty in the world supply of cobalt was generating a problem in
maintaining smooth production at the Tannoy factories in West Norwood, London and Coatbridge in
Scotland.
During the latter part of 1977 the decision was taken by Tannoy to design a new series of Dual
Concentric drive units using Anisotropic Barium Ferrite magnets. This material is more efficient in
power to weight ratio and had a much higher coercive force leading to fewer problems in
demagnetization under high power or low storage temperatures.
New magnet charging equipment was purchased to supply the much higher magnetizing force needed by the
new material. Magnets are supplied unmagnetized to Tannoy so that the magnet can be magnetized with
all its metal pole pieces in place for higher gap field strength. The process of magnetization is
called 'charging' the magnet and takes place inside a heavy coil that generates an exceptionally
strong magnetic field for a faction of a second to align the magnetic domains within the material.
The first unit to emerge with the Anisotropic Barium Ferrite magnet system was a very high power high
sensitivity midrange unit used in the Buckingham and Windsor cabinet models. This unit subsequently
went on to be used in the Buckingham Monitor and, with further modifications in high power music
concert rigs throughout Europe.
dzhanikyan@gmail.com
- Пока не воспользовался интернетом, не знал, что на свете столько идиотов. © Ст. Лем
Аргументы (словеса) - ничто, факты, в виде реального звучания - всё.
- Пока не воспользовался интернетом, не знал, что на свете столько идиотов. © Ст. Лем
Аргументы (словеса) - ничто, факты, в виде реального звучания - всё.
….мне, собственно, и нужна была поддержка….в раздумье. С одной стороны, вроде бы новая игрушка, с другой вечная тема кобальта. Наверное, куплю по-любому. Вопрос не на мильён. Побалуюсь, там видно будет.
Ужоскакой. Господа, вот из современных лучшее решение в фильтр 
:idea: 
Они что, даже этого не знают?! 