Impression Changes of a Live Stage by Lighting in Terms of a Virtual Pop Idol Show

In recent years, LEDs have replaced halogen bulbs or incandescent bulbs for lights on stages. The response time of the LEDs is shorter than those of halogen bulbs and incandescent bulbs, therefore it has become easier to control lights temporally and complex lighting patterns are being used for live music shows especially in pop music. Due to the COVID-19 pandemic, internet distribution of concerts has become popular. Especially, virtual idol’s live shows (-e.g., Hatsne Miku’s live shows-) have become very popular in the two years in Japan. In the present study, audio-visual stimuli with different areas of the stage illuminated by lights and the various colors of the illumination were prepared and live pop music shows performed by a virtual idol, Miss Monochrome were synthesized using the software SHOWMAKER. In Experiment 1, the color of the lights was fixed at light blue, and the area of the lights illuminated on the stage was varied for the live music stage performed by the virtual idol. These 30 synthesized videos were used as stimuli in a perceptual experiment. Fifteen participants rated their impressions of the video stimuli using the semantic differential method. The results of factor analysis showed that the impressions were spanned by three factors, power, tension and tightness. It was also shown that the wider the area illuminated, the more powerful and tighter it come to be perceived. In Experiment 2, nine different areas of illumination on the stage were selected from the areas used in Experiment 1, and twelve colors of the lights were selected from the color wheel. Then 97 stimuli were constructed. Fifteen participants were presented the stimuli through a computer monitor and headphones, and requested to rate the impressions of each of them using 24 paired semantic differential scales. The results of the factor analysis showed that the impressions of the stimuli were illustrated by a three-dimensional space spanned by power, tension and lightness. The results also showed that the wider the area illuminated, the more powerful and tighter it come to be perceived. Moreover, a warm color of the lights was perceived as tense and a cool color was perceived as loose. A prime color was perceived as heavy and a mixed color was perceived as light.