Last week I was listening to an interview with guitarist Taylor Levine on My Ears Are Open. In the interview Taylor talks about how quickly rock musicians adopted technological innovations that created new timbres. From the electric guitar of Les Paul, to innovations in speakers and pedals, to synthesizers of all different generations, as soon as a new device was invented, it was embraced by some popular musician and loved by audiences. Why is it that these musical explorations are so quickly accepted in the popular music world, and yet innovations in timbre in the art music world don't find a foothold, either with the musicians or the audience?
I think there may be a complexity issue that hampers exploration in the art music scene. Berlyne's inverted U theory of complexity and arousal states that the complexity or novelty of a piece directly affects the arousal, with the optimal amount of arousal created at a midlevel of complexity, the arousal dropping off in either direction as the complexity increases or decreases. I posit that popular music tends to be on the low side of the complexity curve, when considering rhythm, melody, and harmony. Thus any experimentation with timbre will only aid in reaching the apex of arousal. On the other hand, a string quartet by Webern already has very complex form, harmony, and melodic structure. I always felt that throwing in extra timbral effects like col legno was like too much spice, pushing me well over the hump of the inverted U curve, reducing my arousal. Musical works that introduce new timbres successfully will be conservative in other aspects of structure. Thus popular music, minimalist music, and non-pitched percussion music tends to be the most successful. A Stockhausen piece that serializes timbre along with rhythm, pitch, and dynamics will have to rely on things other than arousal, at least until audiences are more familiar with the structures, reducing the perceived complexity.