So i used to have the luxury of a separate listening room, which meant easy positioning of speakers and a nice empty space in between (window view or damping material), but living the urban family life that becomes trickier.
It never occurred to me, but initially i had nothing between the speakers (stand mounts with rear ports), then the lumped the mother ship of AV/Storage furniture in between to house the TV/AV/Network as well as lots of junk to be stored out of site.
I cannot recall a deterioration, but speaking with someone recently, as i am looking to room acoustics tweaks, they balked at having anything in between obstructing the speakers.
I find even though the AV unit is nearly as talk as the speakers and they are positioned close to its sides, i am very happy with the sound stage, imaging. to the point i sometimes this how the heck does it do that.
It greatly depends on whether the racks come forward enough to catch reflected sound. If course, speaker cabinets themselves emit vibrations which are factored into speaker design and those will hit anything between speakers.
However, being completely honest, I find the following have more impact than racks between speakers:
objects between the listener and speakers. Such as coffee tables. Remove one and hear a pretty huge difference.
Psychological effect of objects between speakers. I find that I may be weak minded here because an empty space lets me visualise the performance much better.
I have found find that it makes little or no difference to my ears and with my systems, whilst some others are convinced that it makes a significant difference.
My personal view is that any perceived difference can probably be put down to psychological factors in many cases. Of course, if you find that leaving an unobstructed space between speakers does improve some aspects of sound quality (whether psychological or not) and you have the space to accommodate this, then why not. It’s not something that worries me one way or the other, and I actually have a subjective aesthetic preference for hi-fi system components to be placed between speakers.
If the coffee table is beneath the path from speakers to you it’s presence may affect early reflections - though whether beneficially or otherwise would depend on whether it blocks reflections from the floor more than it adds shorter path reflections of its own would depend on the floor and table materials and the position… And even if not beneath said path, it will affect other sound waves, so some audible difference is not surprising.
Much could depend on the speakers themselves. If you play loudly and feel them, they might not vibrate, although some will.
This could indicate their susceptibility to boundary interaction, and how they could influence nearby racked kit.
Reflections are directly proportional to the sound level, so will have the same proportionate effect regardless of how loud or soft you listen, though in terms of hearing there may be a variation with perceived level towards the frequency extremes. Of course, if sound levels are sufficient to stimulate noises arising from vibrations of the table itself, or things on it, then that is a different matter.
(N.B. the speakers don’t vibrate, you won’t hear anything from them )
My personal experience is that moving the gear out from between the speakers absolutely improved the sound stage. I’ve never said that about cable dressing, or about any given ethernet cable . . . but this change made a difference to my ears.
On the original old old forum JV discussed the reasons for this. He basically said that the points/corners of the furniture/racks acted as points to introduce diffraction effects with unpredictable consequences to SQ.
I find personally that having stuff between the speakers stops being a problem when I close my eyes!
For what its worth my racks are between the speakers but close to the front wall and the speakers are considerably forward with the backs of the speakers well in front of the racks. Don’t know if this negates any potential negative effect but I have justified it in my mind anyway. No comparisons since I never had it any other way.
My thoughts are nearly the same as those from @feeling_zen.
The only thing I can add is that low racks between the loudspeakers work well for me. I don’t know why, might be a psychological effect as they are less intrusive than taller ones or fewer diffractions, possibly both
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