This guy is a master at making a two minutes answer take 20 mins. The common-sensical reply is between 4:20 and 5:20 if you want to skip the chatter.
Yes, anything between the speakers can impact the image, but in real life we have many constraints and not just cable length to deal with. Most of us place the system in our living room and we can’t have the unruly cables visible. So we need some kind of rack or cabinet. Also many of us have only one wall in our living cum dining room where we can have both the TV and the speakers (even stereo). Some of us also have same HT system for both movies and music. In short, there are ample reasons to necessitate having equipment, rack and TV between the speakers.
So what can we still do? Firstly, pull out the speakers as much as possible into the room (way from the front wall). This will increase the distance between the speakers and the TV as well as the cabinet/rack. Also move the rack or cabinet as close to the wall as possible. In case of cabinet, that will also reduce the formation of air pocket behind the cabinet which can spoil the sound.
In my case, I made my solid wood cabinet way before I got into home stereo. And I love it - it adds classic charm to the living room. I can’t think of replacing it with an open audio rack (unless very carefully designed). Thankfully my cabinet’s height is short and ends just below the lower edge of my bookshelves. I made a short and long cabinet also because I like my TV sitting on it... I hate the look of a TV hanging on the wall.
View attachment 47865
I have had my struggles with the resonances from the cabinet and imaging. With time and experimentation (and some able guidance) I have been able to minimise the ill-effects on the sound (though they cannot be nullified altogether). I have done all the adjustments pointed out in a paragraph above. Incidentally, the heavy plasma TV sitting on top of the cabinet actually helps keep the cabinet resonance down with its weight. My speakers have a clear 72 cm behind them and the front wall now (plus 32 cm depth of the speaker itself). That allows me to have the cabinet and TV too without significantly adverse effect on the sound.
The idea is, we have to work within out constraints and figure out the best possible workable solution.
If I go for a revamp in future, I will get a custom made solid wood cabinet made - not an open rack, but with doors and back panels with speaker grill kind of material to get the best combination of aesthetics and sound. And unless I go for a projector, the TV will have to sit on the cabinet.