Flatscreen between speakers

@asctim 

When thinking about cancellation and reinforcement of sound, I would encourage you to think about the wavelengths of sound waves in the audible spectrum - Google AI thinks:

The human audible spectrum encompasses frequencies from approximately 20 Hz to 20 kHz. Correspondingly, sound wavelengths within this range in air at standard temperature and pressure vary from about 17 meters (56 feet) at the low end (20 Hz) to 17 millimeters (0.67 inches) at the high end (20 kHz). 

So there is usually lots of distance between speakers and listeners to hold many complete waves for most frequencies, and even between the drivers in one speaker!  There are pictures in this thread where the distance from a main speaker to one driver in the centre channel is about the same as the distance between the outer drivers in the centre channel.  No wonder it sounded better with a smaller centre speaker.

I would also encourage you to explore multi-channel recordings from France and other parts of Europe mainly to the North.  Several thousand classical SACDs are available, for example from Presto.  Most include a CD layer, so you can compare two-channel CD quality with DSD, which is usually on the disk both as two-channel and multi-channel.  SACD has now been around for almost a quarter of a century and these days most cost the same as a CD.  It is hard to find a streaming service that offers multi-channel DSD?

Studios have offered more than two channels since the 1970s, both on tape and quadraphonic records. The CD standard mentions expansion to 4 channels.

Today Dolby Atmos offers up to 32 channels - something being used by some engineers.  Dark Side of the Moon is quite something.  But the best exponent in my opinion is from Norway - Morten Lindberg and his label 2l.no.  I remembered rave reviews in Gramophone for the classic recording Reflections which was released in 2016 in a pack containing a SACD plus a Blu-ray audio disk with many options including Dolby Atmos and 9.1-channel Auro-3D.

Morten Lindberg is willing to leap on anything new - he uses 64-bit formats and floating-point numbers, not the whole numbers we are used to with PCM.  For a lot more depth see Merging Technologies - Use Cases

@richardbrand. Thanks for your thoughtful comment. My personal opinion is that stereophonic was designed to be sufficient for the reproduction of live music. By definition 
“Stereophonic sound, commonly shortened to stereo, is a method of sound reproduction that recreates a multi-directional, 3-dimensional audible perspective”

When done correctly, two speakers can put you right in the venue where the performance is recorded. If you listen to Charles Mingus, Miles Davis and most recordings from that era, you will realize that the weakness in the reproduction chain is the album itself or more precisely, the recording. Take two CDs of the same performance, one from Japan and the other from the USA and you will quickly realize that a lot can be missed from the same performance. If you’re not familiar with BACCH DSP, do a quick search and see how Dr Choueiri was able to restore a lot of that magic back. The problem with multichannel is that it requires a much higher expenditure in money and space. Stereo on the other hand seems simple and clever. 

@spenav 

Not sure where you got that definition of stereo!  The word stereo actually stems from the Greek word for solid.  In modern usage it refers to playback through two or more speakers.  I don't think two-channel stereophonic was designed per se, rather it evolved and continues to evolve, especially outside North America.

The problem with multichannel is that it requires a much higher expenditure in money and space. Stereo on the other hand seems simple and clever.

Never thought an audiophile here would baulk at the cost!  Agree a little bit on space, I've had to find room for two rear tower speakers, but then I deliberately shun a centre channel.  The four height speakers are flush with the ceiling.  On the other hand, my TV (home theatre) shares the same living space as my 'stereo'.

It is quite obvious to me that if you have say 9 channels available, you can always choose to use just two.  Many multi-channel classical recordings tend to use the extra channels for ambience, but some really open up the immersive experience.  Add in video from the Berliner Philharmoniker's Digital Concert Hall and you may be in for a real treat.

Not so much in the pop/rock space but try Dire Straits on SACD, or Pink Floyd in Dolby Atmos.

Personally, I prefer a simple microphone approach, exemplified in the US by Mercury Living Presence, RCA Living Sound and then Telarc.  Set the microphones and recording gear up and let the performers control the balance.

In Australia there was a series of adverts for the Northern Territory, about the most remote tourist destination imaginable.  The tag line was "If you never ever go, you'll never ever know".

@richardbrand 

I've had some experience with multi channel classical, jazz, and rock on SACD and DVD-A. I never had a really good multichannel system so it's fair to say I really haven't tested the possibilities yet.  My house needs to have a bunch of clutter cleared out of a couple rooms. When that's done I may have the space to get a decent multi-channel setup going. I still own the discs.