Equipment Rack Between Speakers...Good or Bad

Primary concern is Turntable of course.

Let's over state the case that 99% of setups have equipment between the speakers.

Music (mono or stereo): there are no center vibrations generated, only the illusion of center, by weak/strong/equal left and right vibrations, so, center can be best.

Video (mono, stereo or surround), Center Channel Speakers and/or TV Speakers, main L/R speakers definitely located just above and beside equipment. 

This is another reason I am not in favor of side, rear or downward firing drivers, radiators, ports, or subs. The lack of direction control especially with corner's random reinforcements is often problematic.

Subs, Music or Video need to be chosen/located with equipment vibration a large consideration, which is why I prefer front firing sub located away from the equipment, in my case on my end of the room, it's front and side blocked from me.

The flexibility of your floors and floor/wall connection should influence whether you couple or decouple your speakers to the floor, and couple/decouple your equipment to surfaces, especially TT.

Speaker enclosure design, to get 'all' vibrations toward you via the drivers, none transmitted by the case itself or movement of the entire case is always best IMO.

There’s worse things you could do. Many of them I can’t talk about because of the you know, banning. 

I would first try pulling the speakers out past the equipment rack. (At least when listening)In my room,absolutely no comparison when speakers are pulled out vs close to the front wall. It goes from music coming out of speakers,to music floating. 

Geez, the chances are actually pretty good you’re sitting smack dab in the middle of a standing wave anyway so what’s the difference? What’s needed is a system. What’s needed is mapping out the whole room with a SPL meter. Then at least you have a baseline. Don’t be a cube, rube. Go ape! 🦍