Gentlemen – I read this term frequently in the paper magazines and on this site too. Usually it is expressed by listeners, and not very well either and from ‘professional writers’ in a somewhat unconvincing way. I rarely here the term defined or at least clarified by a maker. Why is this?
Thank you for your thought-proving question. As to why makers don’t, our guess is that they probably can’t rather than won’t. we tried to construct an answer for you but candidly we weren’t satisfied and so we didn’t. So we sought clarification from the maker side of the industry and we found the following from PS Audio. We hope it helps you.
Openness is obviously the opposite of closed in sounding, but what does that actually mean? Let’s take an example of live music to help me explain what is meant by this.
If I am standing nearby a drum kit and there’s someone hitting the cymbal with the drum stick, the sound I am going to hear is rich with transient harmonics. There’s the initial hit of the stick on the metal and that’s followed by a ringing from the cymbal that extends way into the room, bouncing off walls and seems to permeate the entire space I am in. That’s what I would refer to as an open sound – a sound open to all that is around it and that sound flourishes within the space allotted to it.
A closed in sound would be the same example with the addition of a slight damper placed on the cymbal so it did not ring and produce as many overtones as much as its undamped counterpart.
In a stereo system this same cymbal, if recorded, sounds just like the real deal relative to all the other instruments recorded on the cut. Depending on how good your loudspeakers and playback chain is, you’ll hear much of the ringing as you would live and believe it’s just fine. This is the situation I found myself in with the amplifier – cymbals, stringed instruments sounded great and open – until I heard another amplifier that had better openness.
The harmonics of the instruments opened up as if they had been trapped in a sort of box. Now, the comparison between the two amps was obvious and clear. One was open and the other was closed in – as if a damper had been placed on those instruments that ring and have overtones.
Paul McGowan / PS AUDIO