Flatscreen between speakers

@elliottnewcombjr

Don’t Skip a Center Speaker, even if it has to be small, or behind something, try one

There are very good reasons for not using a centre speaker, especially one which is in effect a horizontal d’Apolito array!  As soon as you move away from dead centre, the outer drivers create an interference effect, or comb filter.  If your main front left and front right speakers have good imaging capability, let them do what they are already good at. 

Your pre-processor should just add the centre signal to the signal for the two front speakers - my Marantz ones all do this.  My main system is configured with two main front speakers, and two rear speakers, plus four ceiling speakers and a subwoofer.

@ticat 

my experience has lead me to believe that 2 channel and HT have no business being seriously pursued in one room

Could you please list where you see the incompatibilities?

Personally, I find 2-channel severely limiting for classical music in particular, where a huge number of recordings is available on multi-channel SACD and other disc formats (Bluray, Dolby Atmos, etc).

Until recently, my main speakers were Quad ESL-2905 driven by a Krell amplifier, and supported by a big subwoofer, so quite good for 2-channel audio.  They are also quite good at providing 2 channels of a home theater system.  My main source is a universal disk transport which retrieves data from CD, SACD, DVD, Blu Ray and 3k disks, If need be, I can switch my turntable through a 2-channel Krell Pre-amp but for everything else I normally used the DACs in my Marantz AV8802 pre-processor.

IF I want to play 2-channel music, I do it through components which would satisfy me in a dedicated room though they are co-located with "home theatre".

Finally, there are awesome recordings of music performances which add yet another channel - video!  Don't want to watch?  Just shut you eyes, but you miss out on the whole experience.

@shooter41 

What an arrogant response. "Where it belongs" is your opinion, not a fact.

Agreed - I was hoping for a sensible response!

@devinplombier 

Doesn’t your LG OLED have built-in works of art to make it look like a picture frame?

I think these OLEDs are brilliant and the very thin panels have almost no effect on sound transmission or reflections.  Sony’s version fires its main speaker through the panel.

I can see that my old Pioneer plasma may have some sonic effect, because it is glass faced and so thick and heavy.  But really, how much sound do most speakers manage to spray out sideways?  Or is the TV panel complicit in re-reflecting sound waves bounced back off the wall behind the listener?

I am thinking about (real) cinemas seating hundreds in a rectangular space, some well to the sides, where a centre speaker behind a fabric screen does make sense for some of the people some of the time.

@knownothing 

Blu-ray soundtracks sounded great pretty much from day one

I don't know what your set-up is, but do you have a centre-channel speaker?  If so, what do you do with it when playing two channel stereo?

If a flat panel TV interferes with your sound quality, surely a purpose-built resonator like a dynamic speaker would be worse?

@samoh 

I discovered that the phantom center image that my speakers create 

I am getting confused here about the word phantom!  

I am happy to call the synthetic cente channel created by some processors from 2-channel sources "phantom" because it does not exist in the real source.

On the other hand, many multi-channel recordings do have a genuine centre channel.  For those like me who choose not to have a centre speaker, it can be added to front left and front right.  Our brain / ear system seems to have no problem recreating it - it is just part of what we call imaging.  To my mind, it is not "phantom"

@asctim 

So phantom centre describes imaging where the subject is dead centre!  Are there terms for where all the other sound sources might be located?

In the old days of classical stereo, recordings were made using a very small number of microphones (two or three being common) and the imaging "trick" was pulled off to great effect - no need for "multiple, near identical, time aligned sound sources" to be electronically processed

@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

@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".

@spenav 

Amazing how two people can interpret the written word so differently!  From your Wikipedia definition:

Because the multi-dimensional perspective is the crucial aspect, the term stereophonic also applies to systems with more than two channels or speakers such as quadraphonic and surround sound. Binaural sound systems are also stereophonic.

Then you quote a US patent filed some 40 years after the pioneering work by Alan Blumlein which was patented in the UK in the 1930s!  In Australia we have a clear distinction between Patents and Trademarks

The word "stereophonic" itself is not trademarked. It's a descriptive term referring to sound reproduction using two or more channels, and therefore cannot be trademarked

The Wikipedia article discusses the use of close microphones and subsequent artificial mixing for pop/rock and then notes:

Classical music recordings are a notable exception. They are more likely to be recorded without having tracks dubbed in later as in pop recordings, so that the actual physical and spatial relationship of the musicians at the time of the original performance can be preserved on the recording

I absolutely agree that two-channel recordings can be stunning - I currently buy anything Decca (London to you?) puts out on CD with Klaus Makela conducting (unlike most European classical record companies, Decca does not seem to do SACD).  My main speakers emulate point sources of sound and throw a huge soundstage with a sweet spot you can walk around in.

Many years ago I auditioned Duntech Sovereign speakers which each contain 7 drivers in a vertical d'Appolito configuration.  They weigh 190-kgs each and are precision time-aligned.  I found that moving my head vertically by just a couple of inches suddenly produced the huge soundstage, then just as suddenly it disappeared.  John Dunleavy used the apparent point source Quad ESL-63 as his reference, which were many times cheaper and had a huge sweet spot but could not play as loud!

Most centre-channel speakers use d'Appolito configurations, but sideways.  Enough said?

What do you do with your centre channel when you are playing two-channel?

@spenav 

Ah, but you used the term to strongly imply two-channel and you also imply there is only one format and that it was designed by "the inventor" rather than evolved over time.

My personal opinion is that stereophonic was designed to be sufficient for the reproduction of live music. ...  When done correctly, two speakers can put you right in the venue where the performance is recorded

Morten Lindberg, I think correctly, says audio is an illusion.  Somehow our ear / brain system builds up a ’picture’ and basically it can be fooled into ’seeing’ a soundstage just as the eye / brain system is fooled into seeing moving images.

I would encourage you to go online to 2l.no and buy a copy of Reflections.  You probably already have a Blu-ray player to feed your Dolby 9.4.4 setup.

I think single apparent source speakers improve the illusion because they don’t muddy the waters with interference effects from different pathlengths, and they don’t produce incoherent reflections from walls, floors, ceilings and maybe TVs.  The Duntech example I gave is the other extreme, where the multiple, separate drivers interfere quite severely between themselves.

I could only find the ClairAudient 1+1 V5 on the web and in its blurb was amused to discover that it is the most unique (there are no degrees of uniqueness, it either is or it isn’t) and that it eliminates the need for desperate drivers (plenty of those where I live)

The 1+1 V5 Personal Reference Monitors are the most unique small footprint loudspeaker in the world. They feature a highly refined proprietary wideband driver eliminating the need for desperate drivers

I see it actually has two full-range drivers in a bipole arrangement, and passive radiators.  You are worried that your plasma TV needs damping but passive radiators are OK?  By the way, if I did want a centre channel, the Audience might well be ideal!

@spenav

Thanks for reporting back on the fruits of your labour!  Must admit I like the look of the diffusing panels.

I've now had a virtual look at your system and see you already have everything you need for 'immersive' sound, except possibly silver disks for the source!

I know you believe that for 'solid' sound, two channels are necessary and sufficient. I argue that two channels are necessary but not necessarily sufficient.

So can I suggest another experiment for you to report back on, which is even less expensive.  Just pop an "immersive" disk (multi-channel SACD or Blu-Ray) into your Oppo and let your Marantz processor use all its channels as it thinks best. Preferably connect them via an Ethernet-capable HDMI cable.

Many of the recordings from Norwegian label 2l.no ship with hybrid SACD and Blu-Ray containing an assortment of hi-res formats.  I've suggested Reflections which is classical but there are many Grammy nominations in their catalogue.

Love to get your reactions .