Let's take our audiophile hats off for a moment, and ask: In general, what do we usually think of when we hear the word "bloom"? Speaking for myself, I think of a flower. When a flower blooms, what does it do? It radiates in all directions. In music/audio, that is exactly what "bloom" means. It is the sense that the sound of a sonic image radiates in all directions. It creates a sense of dimensionality, with an audible sense of the sound projecting not just forward, but also sideways, and to the rear. Additionally, contrary to the audiophilic quest for the elusive "black space between images", there is a sense of great energy in those spaces; rich with the overtones, and undertones of each image.
That is what happens when an acoustic musical instruments play in a real space. Their sound is projected in all directions. The fundamental tones, and overtones (harmonics) of each note that is played create "difference tones". These difference tones are the result of two notes (frequencies) creating a lower tone, which is the difference in frequency of the two original notes. This process is repeated a practically infinite number of times in the course of a musical performance, creating an incredibly complex sonic soup. The ability of a component to pass that much information through is also referred to as the ability to resolve, or pass low level information. However, "bloom" is not a quality that a component should bring to the table. True bloom is something to be retrieved from a recording. The test is simple: If all recordings sound "bloomy" through a given component, that "bloom" is a distortion. Recordings are subject to the limitations of the equipment used to make the recording. In other words, not all recordings have "bloom". Some were recorded in a way, or with equipment, that will sound really flat, and two dimensional, with little sense of the expansion of overtones; without any "bloom". But the great recordings, when played back on equipment that can resolve that subtle low level information will sound, as we all know, fantastic.
That is what happens when an acoustic musical instruments play in a real space. Their sound is projected in all directions. The fundamental tones, and overtones (harmonics) of each note that is played create "difference tones". These difference tones are the result of two notes (frequencies) creating a lower tone, which is the difference in frequency of the two original notes. This process is repeated a practically infinite number of times in the course of a musical performance, creating an incredibly complex sonic soup. The ability of a component to pass that much information through is also referred to as the ability to resolve, or pass low level information. However, "bloom" is not a quality that a component should bring to the table. True bloom is something to be retrieved from a recording. The test is simple: If all recordings sound "bloomy" through a given component, that "bloom" is a distortion. Recordings are subject to the limitations of the equipment used to make the recording. In other words, not all recordings have "bloom". Some were recorded in a way, or with equipment, that will sound really flat, and two dimensional, with little sense of the expansion of overtones; without any "bloom". But the great recordings, when played back on equipment that can resolve that subtle low level information will sound, as we all know, fantastic.