Fusing Pop Music and Light Shows: The Link Between Music and Light Effects
Pop music and captivating lights effects have become an inseparable pair. The circuits responsible for creating these mesmerizing effects span a spectrum from simplicity to complexity. The circuit introduced here represents a straightforward yet intriguing approach, manifesting as a running light display. Its rate of change is intricately tied to the sound’s frequency and intensity. The signal’s journey commences by being directed to the clock input of counter IC1, facilitated by a single-transistor amplifier, T1. For optimal performance, the amplified signal must attain a level surpassing the counter’s switching threshold, while its frequency dictates the frequency at which the counter receives clock pulses.
Signal Source Flexibility: Preamplifier or Microphone Input
The signal source offers versatility, as it can be supplied either by the output of a preamplifier or through an electret microphone connection, as exemplified in the diagram. The latter option operates in a completely contactless manner. Once the signal is suitably amplified, it proceeds to IC1 via IC3, which governs the circuit’s sensitivity. Given that audio frequencies are often too high to deliver a visually appealing effect, IC1 scales down the signal frequency. This adjustment is achieved when S1 connects pin 11 to pin 15. When the switch resides in the alternative position, linking pin 2 to pin 15, the counter divides by 1, causing the light effect to take on a distinct character, departing from its original running light appearance.
Dynamic Running Light Display: Utilizing IC2 and IC1 Integration
The core of the running lights effect lies in IC2, a counter featuring an integrated 1-from-10 decoder. This component is meticulously synchronized by the QO output of IC1, ensuring precise clocking. IC2’s ten outputs are each connected to an LED, guaranteeing that one LED remains high at any given time. The LEDs share a common bias resistor, R5, in an arrangement made possible by the fact that only one LED illuminates simultaneously, even though it might appear otherwise due to the rapid switching.
Expandability and Additional LED Integration
For those seeking an expanded lights display, the circuit offers room for enhancement. An extra LED can be incorporated at pin 12 of IC1, requiring its own resistor rated at 560 Ω. To power this setup adequately, the power supply must deliver a current of up to 100 mA, although at lower frequencies, the current demand significantly decreases. Furthermore, the choice of LED colors is entirely customizable, catering to individual preferences and aesthetics.
