1. A method for adapting a loudspeaker to a specific listening position relative to the loudspeaker by correcting acoustic power radiated by the loudspeaker by means of a correction filter inserted in the signal path through the loudspeaker, the method comprising:
(i) measuring, at an actual listening position, a first quantity characterising the acoustic power radiated by the loudspeaker;
(ii) measuring, at a reference listening position, a second quantity characterising the acoustic power radiated by the loudspeaker;
(iii) using an electronic comparison means to determine a response of a correction filter by a comparison between said first quantity and said second quantity;
(iv) implementing said correction filter; and
(v) inserting said correction filter in the signal path through the loudspeaker, and
wherein said first and second characterising quantities are radiation resistances measured at the actual listening position and the reference listening position, respectively.
2. The method according to claim 1 where the frequency response of said correction filter is given by
LISTENER
\u2062
\u2062
(
f
)
=
R
m
,
r
,
reference
\u2062
\u2062
listening
\u2062
\u2062
position
\u2061
(
f
)
R
m
,
r
,
actual
\u2062
\u2062
listener
\u2062
\u2062
position
\u2061
(
f
)
where Rm,r,reference listening position is the radiation resistance at the reference listening position as a function of frequency, and
Rm,r,actual listening position is the radiation resistance at the actual listening position as a function of frequency.
3. The method according to claim 2 comprising a further adaptation of the loudspeaker to the actual position in the listening room in which the loudspeaker is placed by means of a correction filter, the frequency response (Amp(f)) of which is given by
Amp
\u2061
(
f
)
=
R
m
,
r
,
reference
\u2062
\u2062
loudspeaker
\u2062
\u2062
position
\u2061
(
f
)
\xb7
R
m
,
r
,
reference
\u2062
\u2062
listening
\u2062
\u2062
position
\u2061
(
f
)
R
m
,
r
,
actual
\u2062
\u2062
loudspeaker
\u2062
\u2062
position
\u2061
(
f
)
\xb7
R
m
,
r
,
actual
\u2062
\u2062
listening
\u2062
\u2062
position
\u2061
(
f
)
4. The method according to claim 3, where the radiation resistances at the actual listening position and reference listening position are measured by means of the loudspeaker adapted to the actual position in the listening room.
5. The method according to claim 3, where the radiation resistances at the actual listening position and reference listening position are measured by a dedicated sound source.
6. The method according to claim 1, wherein the radiation resistances measured at said reference loudspeaker and measured at the listening positions are replaced by predetermined radiation resistances.
7. The method according to claim 6, where said predetermined radiation resistances are the free field radiation resistances being a function of f2.
8. A system for adapting a loudspeaker to a specific listening position in a room relative to the loudspeaker by correcting acoustic power radiated by the loudspeaker by means of a correction filter inserted in the signal path through the loudspeaker, said system comprising
a processing unit means that determines a response of a correction filter by a comparison between said a first quantity measured at an actual listening position that characterizes the acoustic power radiated by the loudspeaker and a second quantity measured at a reference listening position that characterizes the acoustic power radiated by the loudspeaker; and
filter means for implementing said correction filter based on transfer functions LS(f) and LISTENER(f),
where
L
\u2062
\u2062
S
\u2061
(
f
)
=
R
m
,
r
,
reference
\u2062
\u2062
loudspeaker
\u2062
\u2062
position
\u2061
(
f
)
R
m
,
r
,
actual
\u2062
\u2062
loudspeaker
\u2062
\u2062
position
\u2061
(
f
)
,
\u2062
\u2062
and
LISTENER
\u2061
(
f
)
=
R
m
,
r
,
reference
\u2062
\u2062
listening
\u2062
\u2062
position
\u2061
(
f
)
R
m
,
r
,
actual
\u2062
\u2062
listener
\u2062
\u2062
position
\u2061
(
f
)
.
9. A system according to claim 8, said system furthermore comprising means for storing either predetermined radiation resistances or measured radiation resistances.
10. A system according to claim 8 furthermore comprising a dedicated sound source for carrying out measurements of radiation resistance at the actual listening position and at the reference listening position.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. Medical or dental-medical handpiece comprising a forward end region defining a lateral insertion opening for a tool and, lying opposite to the insertion opening, a mounting opening having a free edge region with an insert part, which can be placed therein, and a push button displaceably mounted between an outer initial position and an inner release position and biased into its initial position by a spring force, in which initial position the push button is supported with at least one stop arranged thereon one at least one counter stop,
wherein the insert part is disposed sufficiently far into the mounting opening that there remains in the free edge region of the mounting opening a hollow cylindrical guide section, and the push button is adapted to the cross-sectional size of the guide section with slight play for movement and engages therein;
wherein the stop is arranged on the inside of an inwardly extending ring wall of the push button.
2. Handpiece according to claim 1,
wherein at least one of
the stop and the counter stop is elastically yielding transversely of the displacement direction of the push button so that when the push button is pushed in or pushed out with a pushing force exceeding the necessary stop force, the stop or counter stop elastically deflects and self-actingly springs back into the initial position.
3. Handpiece according to claim 1,
wherein
the stop is formed by means of ring beading on a ring wall defined in the push button.
4. Handpiece according to claim 3,
wherein
a plurality of counter stops are distributed segment-like on the periphery of the ring wall.
5. Handpiece according to claim 4,
wherein
the counter stops are arranged on a plurality of spring arms distributed on the periphery of the ring wall, which spring arms stand up from the insert part approximately axially towards the side away from the insertion opening.
6. Handpiece according to claim 5,
wherein
the spring arms extend approximately axis-parallel.
7. Handpiece according to claim 1,
wherein at least one of
the stop and the counter stop has oblique or rounded lead-in surfaces.
8. Handpiece according to claim 1,
wherein
the push bottom has a hat-like cross-sectional form and the ring waii is constituted by means of the peripheral wall of the push button.
9. Handpiece according to claim 1,
wherein
the insert part is a screw part.
10. Handpiece according to claim 9,
wherein
between the push button and the screw part there is arranged a compression spring.
11. Handpiece according to claim 10,
wherein
the compression spring is shaped hollow cone like.