DESCRIPTION JPS5663127

Patent Translate
Powered by EPO and Google
Notice
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
DESCRIPTION JPS5663127
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a general active filter
circuit, FIG. 2 is an equivalent circuit diagram thereof, FIG. 3 is a block diagram of a multiamplifier system, and FIG. FIG. 5 is a block diagram of an amplifier system, FIG. 5 is a diagram
showing an active filter circuit according to the present invention, and FIG. 6 is an output
waveform diagram thereof. 1, 2.3 is a band limiting filter, 4.5.6 is an active filter, and 17.18.19 is
an output terminal. 81 to S7 are changeover switches. II 777-F 1-=--------------J
DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an active filter
circuit, and is applicable to any of a multi-amplifier system and a single-amplifier system. 17
controllable and active filters are becoming more and more busy. FIG. 1 is a general
accompaniment using an operation width-character insertion (An) (AN... (An). The filter is shown,
and the output level is controlled centering on the same wave number (fl to fn) determined by
R1-R4 and C1 to Cn by changing the variable resistors (VRI to VRn). Ru. FIG. 2 shows the
equivalent circuit of FIG. Now, FIG. 6 shows the case where the above-mentioned active filter is
applied to a multi-amplifier type audio amplification circuit, and the output signal of the deck
tuner 0 漕 etc. is a low pass filter 呵 1), a band pass filter 2) The mettc is divided by the bypass
filter (3) v, and the desired same wave number characteristic is given by the active filter + 41 (5)
16) following the above filters. The output of each active filter is a power amplifier having a band
characteristic corresponding to the low pass filter '11, a band pass filter 121, a bypass filter 13)!
! ! + 718 + 19), and a speaker [Wooha-111 m, Skooka (11), tweeter-121) K are applied. By the
way, when the active filter shown in FIG. 3 is used for the Singer Raman system, the output of the
active filter f4115) 16) is milled by the mixing circuit [4) tc as shown in FIG. It becomes the
structure applied to power amplifier IIB and the speaker e. However, using the mixing circuit
which is not present causes problems such as deterioration of V / le down, SZN ratio and
distortion factor. Therefore, in the present invention, in the active filter KM, for the portions
other than the frequency band の determined by the resistors and capacitors that make up the
10-04-2019
1
filter, the characteristics of keeping the input and output cobbles constant are used for each
band. This will be described in detail with reference to the fifth group in which active filters are
connected in series. When the changeover switch (S + 4 to S7) is on the M side (multi-amplifier
side), the output of the band limiting filter (1, 2, 3) is lost through the corresponding active filter
(4, 5, 6) to the output terminal A signal (see FIG. 6a, b1c) which is K-connected and which is
band-limited by a predetermined amount from each output terminal (17, +8.19) is derived.
On the other hand, in the single amplifier (S) side, the negative signal is applied via the bandlimiting filter without passing through the active filter (4, 5, 6) connected in series, and the
output terminal α IK is applied. A tapping signal shown in FIG. 6 + btK can be obtained from the
terminal 1I81. According to the present invention described above, it is possible to obtain an
active filter circuit capable of switching between the single amplifier side and the multi amplifier
side with a simple configuration.
10-04-2019
2