When listening to recordings from the 1930s I am fairly certain I don’t hear the same thing as someone who listened in the ’30s. Even if the sound waves were identical — I could use a Victrola — the context is so changed, my reception of the sound so differently influenced that it’s different music now. Music is a transaction.
When we categorize sound recordings as “music” we may make a misrepresentation. Isn’t this sound, these patterns of sounds, the cause, the inducement, left incomplete without listener response? So for all these decades, we have been recording only part of the story. And of course those sounds are completed into “music” as they are heard each time. This music continues to change. As each listener hears the recordings we have, different music is rendered every time.
In order to record, or preserve, a complete musical transaction we will need to record not only the sounds that are made but the responses they cause. An image of brain activity in the listener perhaps? We may not quite be ready to do it.
But we can have a better sense of old music as it becomes old, if we can record cause and effect. We might have better comprehended Lisztomania described by Heinrich Heine or the fervor induced by Elvis (or now Bieber). Let’s record not just sounds that are made but the complete circuit of music.