In the last few posts we have been covering a lot of ground centering around the idea that recordings properly made can sound quite live on a good system. Even older recordings from the 1950′s and 60′s still sound remarkably live despite the poor recording equipment they had during the day.
How is it that we know when something we hear on our system is acceptably real or when we should instead mentally catalog it as something other than an attempt at live? The recording engineer might tell you that it was the hall ambience either captured by the main microphones or skillfully added in from another set. But that’s not the answer I am looking for. I want to dig a little deeper into our actual ear/brain mechanisms that verify this information for us.
There’s been a lot of advanced research as of late into how we understand things. Just what does it mean to understand and how do we do it? Visual and auditory events are understood by us and by our fellow creatures that have the ability to see and hear. We understand that when we hear a dog barking in close proximity, we need to turn around and see the dog – determine if he is a threat or just a nuisance – and then take action or disregard. A cat or another dog does exactly the same thing with exactly the same skill sets in their brains. To that extent we are no different.
Studies show quite clearly a couple of interesting things about this: we utilize the exact same areas of the brain for both action and analysis and we compare stored memories of both as our reference guides. This is important to understand because it’s how we make such amazingly accurate comparisons of what we hear and see – using the same brain path for both recording and playback.
Imagine reaching out with your hand and touching a hot stove – instantly pulling the hand back and being in pain. You need only do that once and the memory of the visual experience as well as the results are stored in your brain. The next time you consider performing the same action that stored memory is played back through the exact same part of the brain it went through to perform the action in the same place – only this time it’s at a lower level – and does not cause your hand to move. The action is compared to the results and you make the correct decision you don’t want to do that again.
Advanced animals have exactly the same facilities as do we but then we diverge into greater functionality that no animals possess: imagination.
Imagination is a unique human ability to combine stored memories together and create new ones that have never existed. It is this unique ability that allows us to imagine what a live oboe should sound like in our listening room by “playing it back” in our brains, using the exact same path we processed the information with originally. We can then imagine how this must sound in our room despite the fact no live oboe player has ever graced our listening room.
It is the ultimate A/B tool because we can imagine what a group of performers should sound like in our room and then compare that to what we’re actually hearing.
This ability is what generates expectations – if we’re looking for a live sound we can imagine what that might sound like and set our expectations up to know, in advance, what to expect.
We’ll delve more into this tomorrow. If you’re interested in any reading on this subject I would recommend Louder than words: the new science of how the mind makes meaning.
Paul McGowan – PS Audio, Intl.