United States Patent |
4,777,529
|
Schultz
,   et al.
|
October 11, 1988
|
Auditory subliminal programming system
Abstract
An auditory subliminal programming system includes a subliminal message
encoder that generates fixed frequency security tones and combines them
with a subliminal message signal to produce an encoded subliminal message
signal which is recorded on audio tape or the like. A corresponding
subliminal decoder/mixer is connected as part of a user's conventional
stereo system and receives as inputs an audio program selected by the user
and the encoded subliminal message. The decoder/mixer filters the security
tones, if present, from the subliminal message and combines the message
signals with selected low frequency signals associated with enhanced
relaxation and concentration to produce a composite auditory subliminal
signal. The decoder/mixer combines the composite subliminal signal with
the selected audio program signals to form composite signals only if it
detects the presence of the security tones in the subliminal message
signal. The decoder/mixer outputs the composite signal to the audio inputs
of a conventional audio amplifier where it is amplified and broadcast by
conventional audio speakers.
Inventors:
|
Schultz; Richard M. (Marengo, IL);
Dolejs; Raymond (Arlington Heights, IL)
|
Assignee:
|
R. M. Schultz & Associates, Inc. (McHenry, IL)
|
Appl. No.:
|
076113 |
Filed:
|
July 21, 1987 |
Current U.S. Class: |
348/484; 348/61; 380/252; 381/73.1; 381/105; 381/124; 386/102; 434/307R; 434/319 |
Intern'l Class: |
H04N 005/92 |
Field of Search: |
358/93,143,341
380/23
381/73.1,105,124
434/307,319
|
References Cited
U.S. Patent Documents
2338551 | Jul., 1942 | Stanko.
| |
2409058 | Dec., 1944 | Mitchell.
| |
2501327 | Mar., 1950 | Good.
| |
2941044 | Jun., 1980 | Volkmann.
| |
3060795 | Oct., 1962 | Corrigan et al.
| |
3173136 | Mar., 1965 | Atkinson.
| |
3278676 | Oct., 1966 | Becker.
| |
3410958 | Nov., 1968 | Cohen.
| |
3579233 | May., 1971 | Raschke.
| |
3934084 | Jan., 1976 | Munson et al.
| |
3934085 | Jan., 1976 | Munson et al.
| |
4052720 | Oct., 1977 | McGregor et al.
| |
4061874 | Dec., 1977 | Frick et al.
| |
4124943 | Nov., 1978 | Mitchell | 434/307.
|
4230990 | Oct., 1980 | Lert | 358/84.
|
4270284 | Jun., 1981 | Skellings | 434/169.
|
4315502 | Mar., 1982 | Gorges.
| |
4373918 | Feb., 1983 | Berman | 434/307.
|
4395600 | Jul., 1983 | Lundy | 381/73.
|
4396946 | Sep., 1983 | Bond.
| |
4699153 | Oct., 1987 | Shevrin | 128/731.
|
4717343 | Jan., 1988 | Densky | 434/262.
|
Primary Examiner: Britton; Howard W.
Attorney, Agent or Firm: Willian Brinks Olds Hofer Gilson & Lione Ltd.
Claims
We claim:
1. A subliminal decoder/mixer for use in an auditory subliminal programming
system, comprising:
means for receiving at least one audio program signal and at least one
subliminal message signal;
means responsive to the instantaneous amplitude of said audio program
signal for rapidly varying the amplitude of said subliminal message
signal; to maintain said signal at a selected consciously inaudible level
relative to the level of said audio program signal; and
means for combining said audio program signal and said subliminal message
signal to produce at least one composite signal having an audio program
component and a subliminal message component.
2. The subliminal decoder/mixer of claim 1 wherein said means for varying
the amplitude of said subliminal message signal comprises:
rectifier means for generating a control signal indicative of the
instantaneous absolute amplitude of said audio program signal; and
amplifier means responsive to said control signal for amplifying said
subliminal message signal with gain that varies as a function of said
control signal.
3. The subliminal decoder/mixer of claim 1 further comprising:
signal generator means for generating at least one signal having a selected
frequency; and
means for combining said signal with said subliminal message signal to form
a composite subliminal message signal.
4. The auditory subliminal programming system of claim 1 wherein said
subliminal decoder/mixer means further comprises:
signal generator means for generating selected subsonic frequency signals;
and
means for combining said signals with said subliminal message signal to
form a composite subliminal message signal.
5. A subliminal decoder/mixer for use in an auditory subliminal programming
system, comprising:
means for receiving at least one audio program signal and at least one
subliminal message signal;
means for combining said audio program signal and said subliminal message
signal to produce at least one composite signal having an audio program
component and a subliminal message component, the amplitude of the
subliminal message component relative to the amplitude of the audio
program component being such that only the audio program component is
consciously audible;
means for detecting at least one predetermined security code in said
subliminal message signal; and
means responsive to said means for detecting for preventing said subliminal
message signals from being combined with said audio program signal unless
said at least one predetermined security code is detected.
6. The subliminal decoder/mixer of claim 5 wherein said at least one
security code comprises at least one tone signal having selected
frequency.
7. The subliminal decoder/mixer of claim 5 further comprising:
signal generator means for generating at least one signal having a selected
frequency; and
means for combining said signal with said subliminal message signal to form
a composite subliminal message signal.
8. An auditory subliminal programming system, comprising:
audio program source means for generating at least one audio program
signal;
subliminal message source means for generating at least one subliminal
message signal;
subliminal decoder/mixer means for procesing said audio program signal and
said subliminal message signal, said decoder/mixer means comprising:
means for receiving said audio program signal and said subliminal message
signal;
means responsive to the instantaneous amplitude of said audio program
signal for rapidly varying the amplitude of said subliminal message signal
to maintain said signal at a selected consciously inaudible level relative
to the level of said audio program signal; and
means for combining said audio program and subliminal message signals to
produce at least one composite signal having an audio program component
and a subliminal message component;
audio amplifier means for receiving and amplifying said at least one
composite signal; and
audio speaker means for broadcasting said at least one composite signal.
9. The auditory subliminal programming system of claim 8 wherein said means
for varying the amplitude of said subliminal message signal comprises:
rectifier means for generating a control signal indicative of the
instantaneous absolute amplitude of said audio program signal; and
amplifier means responsive to said control signal for amplifying said
subliminal message signal with gain that varies as a function of said
control signal.
10. An auditory subliminal programming system, comprising:
audio program source means for generating at least one audio program
signal;
subliminal message source means for generating at least one subliminal
message signal;
subliminal decoder/mixer means for processing said audio program signal and
said subliminal message signal, said decoder/mixer means comprising:
means for receiving said audio program signal and said subliminal message
signal;
means for combining said audio program and subliminal message signals to
produce at least one composite signal having an audio program component
and a subliminal message component, the amplitude of the subliminal
message component relative to the amplitude of the audio program component
being such that only the audio program component is consciously audible;
means for detecting at least one predetermined security code in said
subliminal message signal; and
means responsive to said means for detecting for preventing said subliminal
message signal from being combined with said audio program signal unless
said at least one predetermined security code is detected;
audio amplifier means for receiving and amplifying said at least one
composite signal; and
audio speaker means for broadcasting said at least one composite signal.
11. The auditory subliminal programming system of claim 10 wherein said
subliminal decoder/mixer means further comprises:
signal generator means for generating at least one signal having selected
frequency; and
means for combining said signal with said subliminal message signal to form
a composite subliminal message signal.
12. The auditory subliminal programming system of claim 10 wherein said at
least one predetermined security code comprises at least one tone signal
having selected frequency.
13. An auditory subliminal programming system, comprising:
subliminal message encoder means for combining a subliminal message with at
least one predetermined security code to produce an encoded subliminal
message; and
subliminal decoder/mixer means for receiving a subliminal message and an
audio program, said decoder/mixer comprising decoding means for detecting
whether said subliminal message is encoded with said predetermined
security code, and mixing means responsive to said decoding means for
combining said subliminal message with said audio program to produce at
least one composite signal having a consciously audible audio program
component and a subconsciously audible subliminal message component only
if said decoding means detects said security code.
14. The auditory subliminal programming system of claim 13 wherein said
subliminal encoder means comprises at least one oscillator means for
generating at least one said security code comprising a tone signal
haveing selected frequency.
15. A subliminal message encoder system for use in an auditory subliminal
programming system, comprising:
means for generating at least one subliminal message signal;
means for generating at least one security code;
combining means for combining said at least one security code and said
subliminal message signal to produce an encoded subliminal message signal;
and
recording means for recording said encoded subliminal message signal.
16. An audio-video subliminal programming system, comprising:
audio-video program source means for generating audio and video program
signals;
subliminal message source means for generating at least one auditory
subliminal message signal;
subliminal decoder/mixer means for processing said audio and video program
signals and said subliminal message signal, said decoder/mixer means
comprising:
means for receiving said audio and video program signals and said
subliminal message signal;
means responsive to the instantaneous amplitude of said audio program
signal for rapidly varying the amplitude of said subliminal message signal
to maintain said signal at a selected consciously inaudible level relative
to the level of said audio program signal;
means for combining said audio program signal and said subliminal message
signal to produce at least one composite signal having an audio program
component and a subliminal message component; and
modulator means for modulating said video program signal for reception by a
television video display means;
audio amplifier means for receiving and amplifying said at least one
composite signal;
audio speaker means for broadcasting said at least one composite signal;
and
television video display means for receiving and displaying the modulated
video program signal.
17. The audio-video subliminal programming system of claim 16 wherein said
means for varying the amplitude of said subliminal message signal
comprises:
rectifier means for generating control signals indicative of the
instantaneous absolute amplitude of said audio program signal; and
amplifier means responsive to said control signal for amplifying said
subliminal message signal with gain that varies as a function of said
control signal.
18. The audio-video subliminal programming system of claim 16 wherein said
subliminal decoder/mixer means further comprises:
signal generator means for generating at least one signal having selected
frequency; and
means for combining said signal with said subliminal message signal to form
a composite subliminal message signal.
19. An audio-video subliminal programming system, comprising:
audio-video program source means for generating audio and video program
signals;
subliminal message source means for generating at least one auditory
subliminal message signal;
subliminal decoder/mixer means for processing said audio and video program
signals and said subliminal message signal, said decoder/mixer means
comprising:
means for receiving said audio and video program signals and said
subliminal message signal;
means for combining said audio program signal and said subliminal message
signal to produce at least one composite signal having an audio program
component and a subliminal message component, the amplitude of the
subliminal message component relative to the amplitude of the audio
program component being such that only the audio program component is
consciously audible;
means for detecting at least one predetermined security code in said
subliminal message signal;
means responsive to said means for detecting for preventing said subliminal
message signal from being combined with said audio program signal unless
said at least one predetermined security code is detected; and
modulator means for modulating said video program signal for reception and
display by a television video display means;
audio amplifier means for receiving and amplifying said at least one
composite signal;
audio speaker means for broadcasting said at least one composite signal;
and
television video display means for receiving and displaying the modulated
video program signal.
20. The audio-video subliminal programming system of claim 19 wherein said
at least one predetermined security code comprises at least one tone
signal having selected frequency.
21. The audio-video subliminal programming system of claim 19 wherein said
subliminal decoder/mixer means further comprises:
signal generator means for generating at least one signal having selected
frequency; and
means for combining said signal with said subliminal message signal to form
a composite subliminal message signal.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to systems for generating auditory
subliminal messages. More particularly, the invention relates to an
auditory subliminal programming system that includes security coding and
decoding and improved automatic gain control of the subliminal message
signal. The programming system of the invention is particularly well
adapted for use in self-improvement programs.
2. Statement of Related Art
It has long been thought that subliminal programming has the capability to
influence the behavioral patterns of listeners. Corrigan et al. U.S. Pat.
No. 3,060,795 and Becker U.S. Pat. No. 3,278,676 are examples of early
work in this area.
One application of auditory subliminal programming to influence the
behavior of listeners has been in the area of anti-theft systems. Lundy et
al. U.S. Pat. No. 4,395,600 discloses an anti-shoplifting system in which
subliminal anti-shoplifting messages are mixed with audio program signals
such as background music, and with a masking signal. The combined signal
is then broadcast via loudspeakers to various areas of a store. In order
to ensure that the subliminal message is broadcast at a sufficient level
to be physically (although not concipously) audible, Lundy et al. varies
the amplitude of the subliminal signal as a function of the level of
ambient noise in the store. However, in order to ensure that the
subliminal message does not become supraliminal, i.e., consciously
audible, during a sharp drop in the ambient noise level, Lundy et al. also
uses a masking signal that quickly responds to changes in the ambient
noise level to mask the subliminal message and prevent such an occurrence.
The amplitude of the audio program signal i.e., the background music, is
separately controlled independently of the ambient noise level.
It is also though that auditory and/or visual stimulation at certain
frequencies enhances the relaxation, awareness, and control of the person
being stimulated. See, for example, Gorges U.S. Pat. No. 4,315,502. The
use of such stimulation in conjunction with auditory subliminal
programming is desirable to further enhance the programming. However,
insofar as the applicant is aware, no system combining auditory subliminal
programming with such stimulation has heretofore been developed.
In particular, an area in which auditory subliminal programming alone or in
combination with such other stimulation can be quite effective and
beneficial is the area of self-improvement programming. For example,
auditory subliminal programming can be used to help the listener stop
smoking, lose weight, improve problem solving techniques, and the like.
In the past, tapes or other audio storage media having pre-recorded
subliminal self-improvement messages mixed with pre-recorded audio
programs such as musical programs have been available. The listener
purchased the tapes and played them through his own home stereo, for
example, to obtain the desired subliminal programming. However, this
proved unsatisfactory to users primarily because they had no control over
the musical selections provided and because the musical selections could
not be changed.
Known prior art systems, such as the Lundy et al. system also have various
drawbacks and lack certain features that have made them unsatisfactory for
use in the personal self-improvement programming area. For instance,
although it is desirable for the level of the subliminal message to track
the higher level of the audio program, thereby optimizing the effect of
the programming, it is unsatisfactory to do so by sensing the ambient
noise level in a location such as the user's living or family room. In
addition, the known systems do not include the very desirable feature of
built-in security in order to inhibit unauthorized and possibly damaging
use of the subliminal programming.
In view of the foregoing drawbacks and deficiencies of the prior art, it is
an object of the present invention to provide an improved auditory
subliminal programming system which is particularly well adapted for use
in personal self-improvement programming.
It is another object of the invention to provide such a system which
combines auditory subliminal programming with auditory stimulation at
frequencies which enhance the relaxation, awareness and control of the
listener for enhanced learning and retention.
It is a further object of the invention to provide such a system which
includes built-in security measures which automatically prevent the use of
unauthorized subliminal program material.
It is still another object of the invention to provide such a system
wherein the quality of the composite signal containing the audio program
and subliminal programming signals is enhanced by automatically
controlling the relative level of the subliminal programming signal as a
direct function of the amplitude of the audio program signal.
SUMMARY OF THE INVENTION
The foregoing objects and attendant advantages are obtained by providing a
subliminal decoder/mixer that receives audio program signals and
subliminal message signals, automatically varies the amplitude of the
subliminal message signals as a function of the amplitude of the audio
program signals, and combines the signals into a composite signal in which
only the audio program component is consciously audible.
With respect to another aspect of the invention, the decoder/mixer detects
whether at least one predetermined security code is present in the
subliminal message signals and prevents combination of the audio program
signals and subliminal message signals unless such code is detected.
With respect to still another aspect of the invention, the decoder/mixer
combines the subliminal message signal with at least one signal having
selected frequency to produce composite subliminal signals.
A subliminal message encoder system is also provided that generates at
least one predetermined security code, combines the code with subliminal
message signals generated by an audio source and records the encoded
subliminal message signals.
With respect to yet another aspect, the decoder/mixer is combined with an
audio program source, a subliminal message source, an audio amplifier and
audio speakers to provide an auditory subliminal programming system.
In another variation, the decoder/mixer is combined with an audio-video
program source, a composite video signal modulator, and a television video
display to provide an audio-video subliminal programming system.
BRIEF DESCRIPTION OF THE DRAWING
The novel features that are believed to be characteristic of the invention
are set forth in the appended claims. The invention itself, along with the
foregoing objects and attendant advantages thereof, will be best
understood by reference to the following detailed description of the
presently preferred embodiments thereof, taken in conjunction with the
drawing, in which:
FIG. 1 is a block diagram illustrating a presently preferred subliminal
decoder/mixer, which embodies various novel features of the invention,
together with related audio components;
FIG. 2 is an electrical schematic diagram illustrating the details of the
subliminal decoder/mixer of FIG. 1;
FIG. 3 is a block diagram illustrating a preferred subliminal message
encoder which embodies various novel features of the invention, together
with related audio components; and
FIG. 4 is a block diagram illustrating an alternative embodiment of the
subliminal decoder/mixer of FIGS. 1 and 2 which is adapted for use with a
video cassette recorder and television.
DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS
Referring to FIG. 1 of the drawing, an audio program source 10 such as a
conventional tape deck, compact disc, or phonograph generates stereo music
or other audio program signals selected by the user on left and right
audio outputs. These signals are conducted to left and right audio inputs
of a subliminal decoder/mixer 25 on lines 15 and 20 respectively.
A subliminal message source 30, which is typically also a tape deck,
compact disc player, or other audio source generates a pre-determined
subliminal message signal which is transmitted to a subliminal signal
input of the subliminal decoder/mixer 25 on a line 35. The subliminal
decoder/mixer 25 decodes the subliminal message signal and detects whether
it contains two selected pre-recorded security tones. The subliminal
decoder/mixer 25 filters the tones, if present, out of the subliminal
message signal and mixes the subliminal message signal with the left and
right audio program signals only if both tones are present. The subliminal
decoder/mixer 25 also controls the level of the subliminal message signal
as a function of the level of the audio program signal, mixes in two
subliminal low frequency signals, and outputs the resulting composite
signals on left and right audio output channels respectively.
The composite signals on the left and right audio output channels are
transmitted to the left and right audio input channels of a conventional
stereo amplifier 50 on lines 40 and 45 respectively. The amplifier 50
amplifies the composite signals and outputs them on lines 55 and 65
respectively to conventional left 60 and right 70 audio speakers. The
listener consciously hears only the audio program he has selected, but
subconsciously also receives the subliminal programming message and the
subsonic frequency stimulation. If the user attempts to use an
unauthorized subliminal message which does not contain both security
tones, the decoder/mixer 25 detects the absence of the tones and does not
mix the unauthorized message with the audio program.
FIG. 2 is an electrical schematic diagram which illustrates the details of
the subliminal decoder/mixer 25 of FIG. 1. The decoder/mixer 25 has three
inputs: a subliminal program signal input on line 35, a left audio signal
input on line 15, and a right audio signal input on line 20. Power is
supplied to the components by any conventional power supply (not shown)
that is capable of full wave rectifying and filtering a 60 Hz AC power
signal and providing +/-12 V and +/-5 V DC operating voltages therefrom.
An RC network comprised of resistor 155 connected between line 35 and
ground and a series capacitor 156 couples line 35 to the input of a
conventional audio input amplifier 160, which is suitably a conventional
negative feedback operational amplifier. The output of the amplifier 160
is connected by line 162 to the signal input of a first notch filter 175.
The output of the first notch filter 175 is coupled to the input of a
second notch filter 180 through an RC network comprised of a resistor 177
connected between the output of the notch filter 175 and ground, and a
series capacitor 178. The output of the second notch filter 180 is coupled
to one input of a conventional summing amplifier 185 through an RC network
comprised of a resistor 182 connected between the output of the second
notch filter 180 and ground, and a series capacitor 184. The notch filters
175 and 180 may be either digital or analog filters, one tuned to each
security tone frequency. A suitable digital notch filter, for example, is
the MF10 notch filter manufactured by National Semiconductor Corp.
The output of the amplifier 160 is also connected by line 162 to the input
of a security tone detect/decode unit 170. The output of the security tone
detect/decode unit 170 is connected by a line 172 to the respective
control terminals of a pair of transmission gates 195 and 200 respectively
which are connected between lines 142 and 147 respectively and ground. The
security tone detect/decode unit 170 is preferably comprised of two
parallel phase locked loops (PLL's) (not shown) each tuned to one of the
security tones. Line 162 is connected to the signal inputs of both PLL's
and the tone detect signal outputs of the PLL's are gated together so that
the output signal of the security tone detect/decode unit 170 on line 172
is low only if both security tones are present. The PLL's are suitably
NE567 PLL's manufactured by a number of companies including Signetics,
National Semiconductor, and Motorola.
A signal generator 190 preferably generates 1 Hz and 12 Hz TTL output
pulses on lines 192 and 194 respectively. Lines 192 and 194 are connected
to inputs of the summing amplifier 185. The signal generator 190 also
preferably generates tuning frequency pulses which correspond to the
frequencies of the selected security tones and outputs them to the notch
filters 175 and 180 on lines 193 and 191 respectively. The signal
generator 190 is preferably comprised of a conventional oscillator (not
shown) having its output connected to one or more conventional counters
(not shown) which count down the oscillator signals to provide the output
signals on lines 191-194 having the desired frequencies. This technique is
well known to those skilled in the art.
The output of the summing amplifier 185 is connected by lines 186 and 187
tpo the signal inputs of voltage controlled amplifiers 140 and 145
respectively. The signal outputs of the voltage controlled amplifiers 140
and 145 are connected by lines 141 and 146 respectively to inputs of
conventional summing amplifiers 120 and 125 respectively.
An RC network comprised of resistor 112 connected between left audio input
line 15 and ground and series capacitor 114 couples line 15 to the input
of a conventional audio input amplifier 116. Likewise, an RC network
comprised of a resistor 113 connected between the right audio input line
20 and ground, and a series capacitor 115 couples line 20 to the input of
a conventional audio input amplifier 117. Audio input amplifiers 116 and
117 may also be conventional negative feedback operational amplifiers. The
outputs of the audio input amplifiers 116 and 117 are connected by lines
118 and 119 respectively to the signal inputs of conventional precision
rectifiers 130 and 135 respectively, and to signal inputs of the summing
amplifiers 120 and 125 respectively. The outputs of the precision
rectifiers 130 and 135 are connected by lines 142 and 147 respectively to
the control terminals of the voltage controlled amplifiers 140 and 145
respectively and to signal inputs of the transmission gates 195 and 200
respectively. The outputs of the summing amplifiers 120 and 125 are
coupled through series capacitors 150 and 152 respectively to left and
right audio output lines 40 and 45 respectively.
Many suitable precision rectifiers are known to those skilled in the art.
One such rectifier which utilizes a two-stage operational amplifier
arrangement and which is suitable for use is illustrated and described in
Roberge, Operational Amplifiers Theory and Practice, 458-460, John Wiley &
Sons Inc. (1975). It is preferred, however, that in the illustrated
rectifier circuit, the transistor in the negative feedback path of the
first stage amplifier be replaced by a diode and that the fixed resistor
in the negative feedback path of the second stage amplifier be replaced by
a variable resistor to provide gain control. Suitable voltage controlled
amplifiers are LM1035 amplifiers manufactured by National Semiconductor
Corp.
FIG. 3 illustrates a presently preferred subliminal message encoding
arrangement for use with the decoder/mixer 25 of FIGS. 1 and 2. A
subliminal message encoder 80 includes a first oscillator 85, a second
oscillator 90, and a summing amplifier 100. The first and second
oscillators 85 and 90 respectively generate at their outputs first and
second security tones having predetermined fixed frequencies. The outputs
of the first and second oscillators 85 and 90 are connected by lines 88
and 92 respectively to signal inputs of a conventional summing amplifier
100. The output of the summing amplifier 100 is connected by a line 105
preferably to a signal input of a tape recorder, compact disc recorder or
other audio recording device.
An audio source 95, which may be a person speaking through a microphone, or
a tape recorder or speech synthesizer or the like, generates at its output
subliminal message signals that will eventually be broadcast to the
listener. The output of the audio source 95 is connected by a line 97 to a
signal input of the summing amplifier 100.
The use and operation of the preferred auditory subliminal programming
system will now be described. Initially the manufacturer of the subliminal
message encoder and the subliminal decoder/mixer 25 determines the number
and frequency of security tones that will be used. In the preferred
embodiment, two tones are used. During manufacturing, the manufacturer
tunes the PLL's of the detect/decode unit 170 and the notch filters 175
and 180 to the selected frequencies, and sets the oscillators 85 and 90 to
the selected frequencies. The manufacturer uses the subliminal message
encoder to produce tapes, compact disks or the like with the subliminal
message and the security tones encoded thereon. Since only the
manufacturer knows the tones selected, it retains control over the content
of the subliminal programming which will be allowed to pass through the
decoder/mixer 25.
Persons desiring to receive particular subliminal programming must obtain a
subliminal decoder/mixer 25 and the tapes or other audio media containing
the desired programming from the manufacturer. The user can verify the
contents of the tapes or other media by playing them on a tape deck,
compact disc player or other suitable audio reproduction equipment and
listening to their contents. To use the subliminal decoder/mixer 25, the
user plugs the left and right audio output jacks of his tape deck, compact
disc player or other audio program source into the left and right audio
inputs of the decoder/mixer 25. The user connects the left and right audio
outputs of the decoder/mixer 25 to the left and right audio inputs of his
stereo or audio amplifier. The user also connects an output of another
tape deck or other suitable audio reproduction equipment which will be the
subliminal message source to the subliminal signal input of the
decoder/mixer 25. The user then plays whatever musical or other audio
programs he selects on the tape deck connected to the audio inputs of the
decoder/mixer 25, and the subliminal program material on the tape deck or
other audio source connected to the subliminal signal input of the
decoder/mixer 25. The user may control the volume of the audio program
using the volume control provided on the tape deck and the decoder/mixer
25 automatically adjusts the level of the subliminal message signal as a
function of the level of the audio program signals.
Referring to the details of the decoder/mixer 25 illustrated in FIG. 2, the
RC networks comprised of resistors 112,113 and capacitors 114,115 AC
couple the left and right audio program signals to the inputs of the audio
input amplifiers 116 and 117 respectively. The audio input amplifiers 116
and 117 amplify the left and right audio signals and output the amplified
signals to the summing amplifiers 120 and 125 on lines 118 and 119
respectively. Assuming that the subliminal message source 30 is not
activated so that there is no subliminal message signal on line 35, the
left and right audio signals pass through summing amplifiers 120 and 125
and are output on lines 40 and 45 unchanged. The gains of the audio input
amplifiers 116 and 117 and the summing amplifiers 120 and 125 are
preferably adjusted to provide unity gain to the left and right audio
signals.
When a subliminal message signal is present on line 35, it is AC coupled to
the input of the audio input amplifier 160 through the RC network
comprised of resistor 155 and capacitor 156. The signal is amplified and
output on line 162 to the series notch filters 175 and 180.
The series notch filters 175 and 180 remove the security tone frequencies
from the subliminal message signal before it is input to the summing
amplifier 185. The summing amplifier 185 sums the filtered subliminal
message signal with the 1 Hz and 12 Hz stimulation signals generated by
the signal generator 190. The 12 Hz signal component assists the listener
in generating alpha brain waves which increase awareness. The 1 Hz
component reinforces relaxation and concentration. If desired, either or
both signals can also be transmitted through light emitting diodes (LED's)
to provide visual as well as auditory stimulation.
In order to maintain the subliminal message at an optimum level with
respect to the level of the audio program, the voltage controlled
amplifiers 140 and 145 control the amplitude of the subliminal signal
output by the summing amplifier 185 with gain that varies as a function of
the instantaneous amplitude of the audio signals. The precision rectifiers
130 and 135 generate unipolar signals with amplitudes the same as the
instantaneous absolute amplitudes of the left and right audio signals.
These signals are scaled and used to control the gains of the voltage
controlled amplifiers 140 and 145.
The variably amplified subliminal signals are then summed with the left and
right audio signals by summing amplifiers 120 and 125 and the composite
signals are AC coupled to the outputs 40 and 45 by capacitors 150 and 152
respectively. The inputs to the summing amplifiers 120 and 125 from the
voltage controlled amplifiers 140 and 145 are scaled with respect to the
left and right audio signal inputs so that the subliminal signals are
continuously maintained at a consciously inaudible level of preferably
about -30 dB with respect to the levels of the audio signals.
The security tone detect/decode unit 170 also receives the amplified
message signal on line 162 and inputs the signal to the two tuned PLL's.
If, and only if, the error signal outputs of both PLL's are low,
indicating that both security tones are present, the gate control signal
output by the detect/decode unit 170 on line 172 is high. A high gate
control signal renders the gates 195 and 200 non-conductive. A low signal
energizes the gates, which then shunt the control signals from the
precision rectifiers 130 and 135 on lines 142 and 147 respectively to
ground. This disables the voltage controlled amplifiers 140 and 145 from
passing the subliminal signals output by the summing amplifier 185 on
lines 186 and 187 and thus prevents the subliminal message signal from
being mixed with the left and right audio signals. Accordingly, only the
left and right audio signals are output on the left and right audio output
lines 40 and 45.
FIG. 4 illustrates an alternative preferred embodiment of the subliminal
decoder/mixer 25 which is adapted for use with an audio-video program
source such as a video cassette recorder (VCR) 205 and an audio-video
output device such as a television 29, for example. In this embodiment,
the subliminal decoder/mixer 25 contains the same circuitry as illustrated
in FIG. 2 and described above. The left and right audio signal inputs of
the subliminal decoder/mixer 25 are connected to the left and right audio
outputs 15 and 20 respectively of the VCR. The left and right audio
outputs of the subliminal decoder/mixer 25 are input to the left and right
audio inputs of television 29 if it is adapted to receive stereo and the
signals are broadcast by left and right television speakers 32 and 33. If
the television 29 is not stereo compatible, either the right or left audio
output of the subliminal decoder/mixer 25 is connected to the monaural
audio input of the television 29. If no such connection is provided, it is
necessary to use a separate audio amplifier and speaker.
In addition, the subliminal decoder/mixer 25 also contains a conventional
RF modulator 26 which receives the composite video output signal of the
VCR 205 on a line 22. The RF modulator 26 converts the composite signal to
a radio frequency signal suitable for display preferably on channel 3 or 4
of the television 29 in a manner well known to those skilled in the art,
and outputs the signal to the television on line 28. Alternatively, if the
VCR contains its own RF modulator or if the television 29 is adapted to
receive the VCR composite video signal, the VCR video signal may be
connected directly to the video input of the television 29 on a line 24,
for example. Thus, in the alternative embodiment of FIG. 4, the listener
may watch a favorite program, for example, while at the same time
obtaining the benefits of auditory subliminal programming.
What have been described are certain aspects of auditory subliminal
programming systems which constitute presently preferred embodiments of
the invention. It is understood that the foregoing description and
accompanying illustrations are merely exemplary and are in no way intended
to limit the scope of the invention, which is defined solely by the
appended claims and their equivalents. Various changes and modifications
to the preferred embodiments will be apparent to those skilled in the art.
Such changes and modifications may include, but are not limited to: the
use of different security arrangements such as pseudo-random codes and
corresponding detectors; the addition or deletion of signal components
from the composite output signals; the use of various different types of
audio program source and subliminal message source equipment such as tape
decks, speech synthesizers, live input, phonographs, and the like; and the
use of different output devices such as headphones or the like. Moreover,
various analog components of the preferred embodiment can be replaced by
equivalent digital components and vice versa. Such changes and
modifications can be made without departing from the spirit and scope of
the invention. Accordingly it is intended that all such changes and
modifications be covered by the appended claims and equivalents.
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