Title:
DISPLAY SYSTEM FOR MUSICAL TONES
United States Patent 3845468


Abstract:
An improved electronic system and display panel assembly are provided which respond to musical tones to produce varying diffused varicolored light patterns synchronized as to color and intensity with the musical tones. The display panel assembly to be described comprises a light diffusing screen, or screens, which enclose a light panel on which groups of differently colored electric lights are mounted. Each group comprises lights of a particular color, for example, and the light of any one or more groups are energized in response to musical tones in a particular frequency band which is selected to activate that group, or groups.



Inventors:
SMITH R
Application Number:
05/296068
Publication Date:
10/29/1974
Filing Date:
10/10/1972
Assignee:
SMITH R,US
Primary Class:
Other Classes:
340/815.67, 340/815.75
International Classes:
A63J17/00; (IPC1-7): G08B5/36
Field of Search:
84/464 40
View Patent Images:
US Patent References:
3440349NOISE LEVEL VISUAL INDICATOR1969-04-22Gibbs
3204513Musical and analytical instrument1965-09-07Balamuth
3163077Color display apparatus1964-12-29Shank
3111057Means for providing variable lighting effects1963-11-19Cramer
2371172N/A1945-03-13Hotchner
1362284Sign1920-12-14Gay



Primary Examiner:
Pitts, Harold I.
Attorney, Agent or Firm:
Jessup & Beecher
Claims:
1. An electrical display panel assembly including: a base; a panel mounted on said base in an upright position to serve as a support member for the assembly; electrically energized illuminating means comprising a plurality of differently colored electric lights mounted on said panel; a first light diffusion screen mounted on said base in an upright position in generally spaced relationship with said panel to serve as a front member for the assembly; a second light diffusion screen mounted on said base between said panel and said first diffusion screen in generally spaced and parallel relationship with said panel and with said first diffusion screen; and electric circuit means including a plurality of electric channels respectively connected to the lights of different particular colors, with filter means included in each such channel to cause the respective channels to respond to electric signals corresponding to musical tones within different predetermined frequency ranges, so that the electric lights of different colors may be energized in response to tones in different frequency ranges, thereby to create harmonizing diffusion

2. The panel assembly defined in claim 1, in which said first diffusion screen has a generally arcuate configuration, and has its ends folded back

3. The panel assembly defined in claim 1, in which said first and second

4. The display panel assembly defined in claim 1, and which includes a top member having generally the same configuration as said base member and extending over the top edges of said panel and said first and second light

5. The display panel assembly defined in claim 4, and which includes a pair of rods secured to the top and extending therefrom at each end of said base, and means securing said base to said rods, said rods serving as a

6. The display panel assembly defined in claim 1, in which said rods are

7. An electrical display panel assembly including: electrically energized illuminating means, and circuit means for selectively energizing said illuminating means in response to signals in a predetermined band, said circuit means including: a filter circuit for producing an output signal in response to signals in said predetermined frequency band, said output signal having an amplitude related to the amplitude of such signals in said frequency band; circuit means for introducing a pulsating energizing voltage to said illuminating means; a ramp circuit connected to said circuit means for producing a ramp signal; and a trigger circuit connected to said filter circuit and to said ramp circuit for causing said illuminating means to be energized for a portion of each cycle of said pulsating energizing voltage as determined by the amplitude of the output

8. The electrical display panel assembly defined in claim 7, in which said

9. The electrical display panel assembly defined in claim 7, and which includes a voltage doubler circuit interposed between said filter circuit

10. The electrical display panel assembly defined in claim 7, in which said circuit means for introducing a pulsating voltage to said illuminating

11. The electrical display panel assembly defined in claim 7, in which said trigger circuit includes a diac and a silicon controlled rectifier

12. The electrical display panel assembly defined in claim 7, and which includes a trap circuit connected to said pulsating voltage circuit means for developing a negative discharge voltage when the voltage of said

13. The electrical display panel assembly defined in claim 4, in which said first and second light diffusion screens have an essentially planar configuration and are removably supported in said panel assembly in slots

14. The display panel assembly defined in claim 13, and which includes a third light diffusion screen supported in slots in said base and top member in essentially spaced and parallel relationship with the first and

15. The display panel assembly defined in claim 13, and which includes end panels for the assembly supported in transverse slots in said base and top

16. The electrical display panel assembly defined in claim 1, in which said first light diffusion screen comprises a sheer fabric material supported

17. The display panel assembly defined in claim 1, in which said electrically energized illuminating means comprises a plurality of differently colored lights mounted in holes in said panel, and extending

18. The display panel assembly defined in claim 17, in which said differently colored lights are arranged in concentric circles, so that the lights of a particular color extend radilly as spokes from the center of

19. The display panel defined in claim 1, and which includes switching means in said circuit means for selectively switching strings of said

20. The display panel defined in claim 19, in which said light strings are

21. The display panel defined in claim 1, in which said support panel is coated with light absorbing material.

Description:
BACKGROUND OF THE INVENTION

Systems have been conceived in the past which attempt to coordinate colors with sounds, and more specifically to cause differently colored electric lights to be energized in response to tones of different predetermined frequencies. The overall effect of such a display system is a spectacular harmonizing of color illuminations with musical sounds. Musical tones are converted into corresponding electrical signals in the systems, and the electrical signals are selectively filtered so as to control the energization of different groups of colored lights. In this way, different color illumination effects are obtained in synchronism with tonal variations of the music emanating from the particular musical source.

The system and apparatus of the present invention provides in one embodiment an improved display panel in which a pair of spaced diffusing screens are used so as to achieve widely dispersed diffusion color illumination patterns in a minimum of space, and particularly within a very thin panel width. A feature of the display of this embodiment if that harsh and sharp outlines are eliminated, and soft and diffused colored light patterns are produced within the aforesaid narrow confines.

The system and apparatus of a second embodiment incorporates a covering of a sheer fabric such as black chiffon which acts as a second screen and masks the first diffusion screen when the apparatus is not operating. The chiffon screen also assists in creating a soft color effect when the apparatus is on. The second embodiment also incorporates unique mounting for the lamps, as will be described. A third embodiment is also to be described in which the light panel is flocked to provide a velvetized effect. The light strings are interleaved in the third embodiment, as will be described, and the electronics module is mounted directly in the unit. The latter embodiment includes rotary switches mounted on the side of the unit for selectively switching the various light strings.

The panel assembly of the various embodiments of the invention, as will be described, is constructed in an improved and simplified manner, whereby the various components of the panel assembly are normally held together in a rigid assembled condition, but can be readily disassembled for replacement of any of the component parts of the assembly, such as diffusing screens, lights and the like.

The improved system of the invention also includes unique and simplified electronic circuitry which causes the lights in the display panel to be selectively energized in response to different musical tones, and also which causes the intensity of the illumination of any group of lights to be dependent upon the intensity of the tone causing the illumination.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a display panel constructed in accordance with one embodiment of the invention, and which may incorporate the concepts of the invention;

FIG. 2 is an exploded perspective view of the screen of the panel assembly of FIG. 1;

FIG. 3 is a fragmentary sectional view taken along the line 3--3 of FIG. 2;

FIG. 4 is a circuit diagram of an appropriate electronic control system for use in conjunction with the panel assembly of FIGS. 1-3;

FIG. 5 is a perspective view, like FIG. 1 of a second embodiment of the invention;

FIG. 6 is an exploded perspective view of the assembly of FIG. 5;

FIG. 7 is a plan view of the bottom member of the assembly of FIG. 5;

FIG. 8 is a cross-section taken along the line 8--8 of FIG. 7;

FIG. 9 is a perspective view of a further embodiment of the invention;

FIG. 10 is an exploded perspective of the embodiment of FIG. 9 on an enlarged scale;

FIG. 11 is a section taken along the line 11--11 of FIG. 10;

FIG. 12 is an exploded perspective view of yet another embodiment;

FIG. 13 is a rear view of the embodiment of FIG. 12 with the rear panel removed; and

FIG. 14 is a circuit diagram showing how a plurality of strings of lights, such as are used in the embodiment of FIGS. 12 and 13, may be selectively switched to different signal channels.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

The assembly shown in FIGS. 1-3 includes, for example, a top 10 which, as shown in FIGS. 2 and 3, for example, has channels therein for receiving a front diffusion screen 12 and an inner diffusion screen 14, and which has a rear shoulder for receiving a lamp supporting panel 16. The inner diffusion screen 14 has an essentially flat planar configuration, and it is supported in an upright condition in the corresponding groove in the base 10.

The aforesaid components are held in an assembled condition by a pair of transparent rods 18-20. The rods 20 are formed, for example, of plexiglass, or any other appropriate transparent material. It is preferable for the rods 18 and 20 to be transparent so that they will not create unwanted shadows in the display produced by the panel.

The front diffusion screen 12 may have, for example, a slightly arcuate configuration, as shown, and the ends thereof may be folded back to engage the ends of the light board 16, and form a complete enclosure for the panel assembly.

A number of electric lamps 24 are mounted on the panel 16 in predetermined patterns, the lamps 24 being of different colors, with the lights of each color being included in a corresponding circuit. For example, the electric leads extending to the panel are connected to a red, blue, green and yellow group of electric lights respectively. Therefore, whenever the "red" lead is activated the corresponding group of red lights are illuminated; whenever the corresponding "blue" lead is activated, a group of blue lights are illuminated, and so on. The electric lights of the various groups may be positioned on the panel 16 in any desired pattern, so as to create a pleasing and harmonizing diffusion pattern on the exterior of the diffusion screen 12.

An important feature of the assembly of the present invention is the inclusion of the two diffusion screens 12 and 14 within the assembly, the screens being spaced from one another and from the panel 16. It has been found with such a construction that fully diffused and pleasing illuminated images may be achieved, without harsh outlines, or the like, within the narrow confines of the panel assembly.

The lamp supporting panel 16 is mounted to the rear shoulder of the base 10 by means of screws, such as the screw 30 (FIG. 3) extending into blocks 32 on the top. A top 40 is also provided having generally the same configuration as the base, and the top is held in place by a pair of screws 36 which are threaded into the upper ends of the transparent rods 18 and 20. Further blocks 44 are provided on the underside of the top 40, and the panel 16 is held in place against the top by screws 48 which may be threaded into the blocks 44.

It will be appreciated that the assembly thus far described may be easily opened for replacement purposes, merely by removing the screws 42 and 30 and the base 10. This permits the screens 12 and 14 to be removed and replaced, if so desired, and it also provides easy access to the lights 24. However, when the components are assembled together in the manner described, a rugged and durable assembly is provided.

The diffusion screens 12 and 14 may be composed, for example, of transparent styrene, acrylic, glass, or any other appropriate material on which diffusion designs are formed. For example, diffusion panels are commercially obtainable, and such panels are presently being marketed by Carolite, Inc., 22600 South Bonita Street, Wilmington, California. An appropriate screen for use in the panel assembly, for example, is the Carolite C-4 prismatic panel which is formed of polystyrene or acrylic, and which has embossed prisms of a pyramidal shape. The pyramidal prism of the said diffusing screen utilizes a precisely designed angle to yield optimum transmission at high angle of incidence, and effectively refract light in the direct glare zone. The Carolite C-4 screen is extruded from light stable polystyrene or acrylic. The Carolite C-55 polystyrene prismatic panel is also suitable, the latter panel comprising a pattern consisting of rows of hexagons embossed at 45° angles for extremely sharp definition. The C-55 screen is extruded from either clear or opalescent light stable polystyrene. It is evident that other types of diffusion screens may be used for the panels of the invention.

As mentioned above, each group of electric lights on the board 16 is activated in response to musical tones in predetermined frequency ranges. The circuit shown in FIG. 4, for example, corresponds to one particular channel, and, for that purpose, includes an active filter oscillator circuit 100 which is activated in response to electric signals from a tape recorder 102, or other appropriate musical source, and which signals correspond to musical tones in a predetermined frequency range, corresponding to the group of lights to be activated by the particular circuit of FIG. 4. It will be understood that other similar circuits are also used for each of the other groups of lights, each having an active filter, such as the filter 100, but responding to different frequency ranges, so that the lights of the display are selectively illuminated as the musical tones vary from frequency range to frequency range. l

The tape recorder 102 has a pair of output terminals at which electrical signals corresponding to the recorded music appear. The output terminals of the tape recorder are connected to a potentiometer 104. The wiper of the potentiometer and a lead from the recorder are connected to the primary winding of an isolation transformer 103. The secondary of the transformer is connected to a resistor 106, and the resistor 106 may have a resistance of 4.7 kilo-ohms. The resistor 106 is connected to a feedback capacitor 108 and to a feedback capacitor 110. The capacitor 108 is connected to the base of an NPN transistor 112 which may, for example, be of the type designated 2N3391. The collector of the transistor 112 is connected to the junction of a pair of resistors 114 and 116, and the emitter is grounded. The resistor 114 may have a resistance of 1 megohm, and the resistor 116 may have a resistance of 3.3 kilo-ohms. The resistor 116 is connected to the positive terminal of the 22-volt source. The collector is also connected through a feedback capacitor 118 and through a resistor 120 to a grounded potentiometer 122. The capacitor 110 is connected to the movable contact of the potentiometer 122. The resistor 120 may have a resistance of 2.7 kilo-ohms, and the potentiometer 122 may have a resistance of 2 kilo-ohms.

The active filter circuit of the transistor 112 may be similar to the active filter described in an article by J. M. Powell in Electronic World Magazine for January 1969 at page 39.

The collector of the transistor 112 is also connected to a coupling capacitor 129 which, in turn, is connected to the cathode of a diode 130 and to the anode of a diode 132. The cathode of the diode 132 is grounded, the cathode of the diode 130 is connected to a grounded resistor 134, and the anode of the diode 130 is connected to the junction of a grounded filter capacitor 136 and a further resistor 138. The diodes 130 and 132 are connected in a voltage doubling circuit. The resistor 134 may have a resistance of 330 kilo-ohms, and it provides for rapid decay of the signal passed through the active filter 100 at the termination of such signal. The resistor 138 may have a resistance of 39 kilo-ohms.

The resistor 138 is connected to the junction of a diode 140 and a diac 142 of the type designated MPT20. The device 142 is also connected through a 270 ohm resistor 144 to the junction of a 2.7 megohm resistor 146 and grounded capacitor 148. The diode 140 is shunted by a capacitor 150. The junction of the resistors 144 and 146 is connected through a pair of diodes 152 and 154 to a lead 156, the lead 156 being connected through a full-wave bridge rectifier 155 to the 115-volt alternating current source. The resistor 146 is connected to a potentiometer 147 which, in turn, is connected to the lights 24. The potentiometer 147 may have a resistance of 2 megohms.

The diode 140 is connected to the gate electrode of a silicon controlled rectifier (SCR) 158, the cathode of which is grounded, and the anode of which is connected through its group of colored lights 24 to the lead 156. The lead 156 is connected to a common trap circuit 160. The circuit 160 includes a diode 162 whose anode is connected through a resistor 136 of 10 kilo-ohms to the lead 156 and whose cathode is grounded. A 2 microfarad capacitor 164 is connected to the anode of the diode 162 and to a 560 ohm resistor 166. The resistor 166 is connected to a grounded 10 kilo-ohm resistor 168 and to the cathode of a diode 170, the anode of which is connected to the lead 156.

In the operation of the circuit of FIG. 4, whenever the source 102 produces a signal in the range which activates the active filter 100, the active filter produces an output signal which is rectified in the voltage doubler circuit 129-138, and which appears as a negative voltage at the right-hand side of the diac 142. The bridge rectifier 155 produces a pulsating full-wave rectified voltage on the lead 156, and this voltage produces a current flow through the lights 24, and through the potentiometer 147 and resistor 146 so as to cause a ramp voltage to appear across the capacitor 148 for each pulsating cycle of the full-wave rectified voltage. The ramp voltage across the capacitor 148 increases in a positive sense, and when that voltage in combination with the negative voltage of the voltage doubler circuit exceeds the threshold of diac 142, the diac 142 becomes conductive, thereby causing the SCR 158 to fire and the lights 24 to be energized.

It will be appreciated that the SCR 158 is fired during each pulsating cycle of the full-wave rectified voltage on the lead 156, and the point in each pulsating cycle at which the SCR 158 is fired is determined by the negative voltage at the right-hand side of the diac 142. The latter negative voltage, in turn, depends upon the amplitude of the signal passed by the active filter 100.

By the circuit and system described above, the intensity of the light 24 is controlled as a function of signal intensity from the source 102, since as the signal increases in intensity, the control of the SCR 158 is such that the SCR remains on for greater portions of each of the pulsating cycles of the full-wave rectified voltage on the lead 156.

The network 160 provides a common trap circuit for all the channels, this circuit producing a negative discharge voltage across the capacitor 146, so that when the capacitor 148 is discharged when the voltage on the lead 156 drops to zero, a "suck-out" effect is provided which assures that the ramp capacitor 148 will be completely discharged between each pulsating cycle of the full-wave rectified voltage on the lead 156.

The embodiment of FIGS. 5-8 includes, for example, a base 210 which, as shown in FIGS. 6-8, for example, has channels therein for receiving a plurality of front diffusion screens, such as the screens 214, 215 and 212. The screens 214, 215 and 212 may be inserted and removed from the assembly, merely by sliding them into the slot in the base 210 and corresponding slots in the top 240.

The screens 214, 215 and 212 may be used in any combination in the embodiment of FIGS. 5-8, and any number of screens may be used. A feature of the embodiment of FIGS. 5-8 is that the screens may be inserted and removed at will, so as to vary the format of the display, and various types of diffusion screens may be supplied with the units. For example, the diffusion screens may have various designs formed therein such as diamonds, circles, squares, hexagons, or "cracked ice."

The embodiment of FIGS. 5-8, and as shown in FIG. 6, for example, includes a lamp supporting panel 216 similar to the light board 16 in the previous embodiment. A pair of transparent rods 218 and 220 formed, for example, of plexiglass, or any other appropriate transparent material, serve to support the unit in an assembled condition. The rods are received by studs 236 in the top 240, and are attached to screws 242 through the base 210. The top is affixed to the rods by studs 236 which are threaded into the rods. As in the previous embodiment, it is preferably for the rods 218 and 220 to be transparent so that they will not create unwanted shadows in the display produced by the panel.

A number of electric lights 224 are mounted on the panel 216 in predetermined patterns, and, as in the previous embodiment, are of different colors, with the lights of each color being included in a corresponding circuit. As before, the electric leads extending to the panel 216 are connected to red, blue, green and yellow groups of electric lights respectively, and the operation of the lights 224 on the light panel 216 is the same as in the previous embodiment.

As in the previous embodiment, the lamp supporting panel 216 is mounted to the rear shoulder of the base 210 by appropriate screws which extend into blocks 232 on the underside of the base 210. The top 240 has generally the same rectangular configuration as the base, and is held in place by the studs 236 which are threaded into the upper end of the transparent rods 218 and 220. Further blocks 244 are provided on the top 240, and the light board 216 is also attached to the latter blocks by screws 248.

The assembly of FIGS. 5-8 also includes side panels 227 which may also be of the same type of material as the diffusion screens 214, 215 or 212. The latter panels are held in place in transverse slots in the base 210 and top 240, and are held in the slots by causing holes in the side panels to engage studs 228 at each end of the light board 216.

The construction of the embodiment of FIGS. 5-8 permits any number of diffusion screens to be used up to, for example, three in the illustrated embodiment, and permits the screens to be replaced by other screens simply by removing one or the other of the end panels 227, and by sliding the screens 214, 215 and 212 out through the end of the assembly.

The embodiment shown in FIGS. 9, 10 and 11 includes, for example, a top strip 94, a bottom strip 60, and a pair of side strips 73 and 71. The strips 94, 60, 73 and 71 may be composed of wood, for example, or any other appropriate material, and they are fastened together to form a frame for the assembly, as shown in FIG. 9. A front diffusing screen 62 is supported in a forward channel 87 which is formed in the inner surfaces of the strips, as shown, for example, in FIG. 10. The diffusing screen 62 may be of the same material as the diffusing screens 12 and 14 described above in conjunction with the embodiment of FIGS. 1-4.

In the embodiment of FIGS. 9, 10 and 11, a sheet of sheer fabric 77, which may be composed, for example, of black chiffon, is stretched over the front face of the diffusing screen 62. It is pointed out that the fabric 77 may also be used in conjunction with the previous embodiments of the invention. The fabric sheet 77 serves to mask the face of the diffusing screen 62, so as to provide an attractive black, or other colored surface, when the unit is not operating. Also, the fabric sheet 77 captures reflected light to provide high contrast, and it assists the diffusing screen 62 in providing a soft color effect when the unit is activated. The fabric sheet also serves to provide a perfectly flat surface even if the diffusing screen bows inwardly.

A lamp support panel 64 is supported in a central channel, such as the channel 85 shown in FIG. 10, and which is formed in the strips 94, 60, 73 and 71. The panel 64 may be formed, for example, of Masonite, or other appropriate material. The lamp support panel is drilled, and a plurality of miniature lamps 74 are supported in the support panel 64 in sockets 76, as shown in FIG. 11. The sockets are mounted in the holes in the support panel 64 in a simple press-fit relationship.

The mounting of the lamps 74 on the support panel in the manner illustrated, and the use of miniature lamps, permits the diffusion panel 62 to be placed in close proximity with the panel 64, so that the overall width of the unit is small as compared with the usual prior art units of the same general type. The surface of the panel 64 may be flocked, or otherwise treated, to capture ambient light and add to the high contrast and depth of the display. The lamps 74 have different colors, as in the previous embodiment, and are energized, for example, by appropriate cables designated 79 in FIG. 9.

For optimum aesthetic effects, it has been found that the lamps on the support panel should be mounted so that the lamps of a particular color extend as radial spokes from the center of the display to the outer perimeter. Then when the lamps are sequentially energized, such as by the circuitry described above, pleasing effects are created, in which color bands appear under some circumstances to rotate about the center of the display.

A lamp supporting panel 64 is supported, for example, in a channel 85 which extends around the inner surfaces of the strips 94, 60, 73 and 71. The strip 73 may be removable, for example, so as to permit access to the interior of the unit, and so as to provide a simple means whereby the diffusion screen 62 and rear panel 66 may be slipped out of the unit, thereby to expose the lamps 74 for replacement purposes. This removal of the screen 62 also permits it to be replaced with other diffusing screens, if so desired. The removable strip 73 is held in place, for example, by screws 75, as shown in FIG. 9.

It is also possible to mount more than one group of color lamps in a particular display, as shown in the embodiment of FIGS. 12-14. In this way the various groups may be interleaved with one another, and the switching effects may control one or the other of a particular group while the unit is being operated, or both groups, depending upon the display desired.

In the embodiment of FIGS. 12-14, a multiplicity of differently colored lamps 190 are supported on a lamp supporting panel 302 in a design such as shown in FIG. 12. The panel 302 may be flocked to provide a light absorbing surface so that light reflected from the diffusing screen 304 may be absorbed. As in the previous embodiment, the diffusing screen is covered by fabric 306 which may, for example, be black chiffon. A back panel 308 is provided, and the panels and screen may be supported in side strips 312, as in the previous embodiment. The lamp supporting panel 302 may provide a mirror surface if desired, and the screen 304 may take the form of a two-way mirror so that a myriad of reflections for each lamp may be produced.

The electronic circuitry 300 for the unit of FIGS. 12 and 13 may be mounted inside the casing formed by the side strips 312, as shown in FIG. 13. Also, an internal switching block 192 (FIG. 14) may be incorporated into the unit, so as to permit the various strings of colored lights 190 selectively to be switched into the activating circuit, or out of the activating circuit, as desired. The switching block, on the other hand, may be incorporated as a remote unit, so as to permit the viewer remotely to make his own selection from time to time. The switching block 192 preferably includes a plurality of multi-position switches shown in FIG. 13, and designated schematically in FIG. 14 as 172a-172h, each of which may be turned from position-to-position to cause a corresponding string of the colored lights 190 to be connected selectively to each of a plurality of phase controls included in the electronics 300 and designated by the respective blocks 174, 176, 178 and 180 in FIG. 14.

The phase controls are connected to corresponding active filters 182, 184, 186 and 188, as shown in FIG. 14, and which also are included in the electronics 300 of FIG. 13. The active filters and phase controls of FIG. 14 may have circuitry in the form shown in FIG. 4. The active filter 182, for example, produces an output in the range of 102 cycles per second, the active filter 184 produces an output in the range of 385 cycles per second, the active filter 186 produces an output in the range of 825 cycles per second, and the active filter 188 produces an output in the range of 3200 cycles per second. As mentioned above, any one of the individual strings of the lights 190 may be selectively connected by the switches 172a-172h to any one of the phase controls 174, 176, 178 and 180 connected respectively to the aforesaid active filters.

The phase controls and active filters shown in FIG. 14 are connected in the same manner as the circuit of FIG. 4, and networks in FIG. 14 finding corresponding in the circuit of FIG. 4 are indicated by the same numerals.

In the embodiment of FIGS. 9, 10 and 11, in which the light strings are arranged in concentric circular patterns provide displays of unique characteristics. For example, the lights in the concentric circles have a tendency to precess in some cases giving the illusion of spinning. Moreover, the lights tend to be illuminated, under other conditions, from the center of the display and radially outwardly, to provide a target effect.

The various light strings of the two groups of the embodiment of FIGS. 12-14 may be interwoven by selective switching in accordance with the control of FIG. 14 so that the different sound channels can be selected to actuate the different strings of each group in any desired pattern, so that an almost infinite combination of patterns can be achieved by the system, merely by manipulating the various switches 172a-172h of the block 192. This provides the viewer with the ability to coordinate color and music to any desired pattern, as may suit his individual preference.

The invention provides, therefore, an improved display apparatus and system, whereby diffused illuminated light patterns are provided in response to corresponding musical tones. It should be pointed out that although particular embodiments of the invention have been shown and described, modifications may be made. It is intended in the following claims to cover all the modifications which fall within the spirit and scope of the invention.