The Big Picture


“Either Way I’ll Get into the Garden”

 

Part of the escape of television and movies is being so caught up the magical world on the other side of the screen that we’re drawn into it.

 

Theaters use a proscenium to frame the stage and serve as a visual cue, a portal by which you, the audience enter the story.

 

In much the same way, the television in our modern home entertainment venue acts as this door into the experience. The TV itself, and its setup, can be supremely vital in how we get immersed in our movies and shows. A conundrum every buyer faces is  “How big a TV should I have?”

 

The answer is not straightforward, but there is a method, rooted in science, that can help guide the decision-making process. Mind you, what we’re discussing isn’t meant as a guideline for casual viewing – truthfully, that becomes far more subjective than objective. The TV in the den or the master bedroom doesn’t need to follow the rules set for critical viewing. What we’re addressing is what you might consider your primary viewing environment, where you are trying to capture the full experience as intended by those that composed it.

 

The first consideration is your field of view. This hinges not only on the size of the display, but the arrangement of the seating. The Society of Motion Picture and Television Engineers (SMPTE) recommends that the picture on the screen encompass 30° of your field of view (FoV), that is to say that if you are staring at the screen, the portion of your view where your focus lies. Depending on the resolution (say, 1080i/p), that 30° arc results in what has been coined the “window effect” where your brain is convinced that what you are viewing is live, being seen through a window or frame.

 

Next, and likely the crucial component in deciding on a screen size, stems from visual acuity and picture structure. Those are fancy terms that for the layman simply reference your seating distance from the display. The ranges of seating distances depend on the resolution of the viewing material and your overall critical eye. The picture accompanying this post is an excellent guide that reflects seating distance ranges for screen sizes based on the source material’s resolution. If you play, as most of us do, a mix of resolutions, say, primarily 1080i/p and 4k material, your best option is to select a seating distance based on screen size that falls on the common line between the two formats. Having been conditioned and trained to look for certain things in the image, I find myself forced to sit at the farthest recommended range for specific resolutions, or I catch a glimpse of something in the picture that pulls me out of the experience. The goal is to just see an image, that “window effect,” not how it is made.

 

The final piece to make it all come together is screen height placement within the room. In most, existing rooms, we are sadly at the mercy of the construction and layout of the room. Often, compromise is made – but where you have control or planning, or can affect a change, this step will benefit your perception of the image quality. Based on a couple human factors, like the way your eyes focus, that natural at-rest position for your head when you are seated, and based on the way displays project (or reflect, like projector/screen combinations) the light to your eye, it is recommended that you mount your screen so that your eyes line up with the bottom ⅓ to bottom ½ of the screen. For example, if when seated, my eye height is 36” up from the floor, the bottom ⅓ of my screen should fall below 36”. This keeps your eyes at rest when watching, prevents strain on your neck, and helps ensure that the proper colors and light output from the display reach your eyes correctly. When using a projector, the screen size is generally quite large, and the seating distance is farther back, and in those cases, a good rule is to mount the screen so the bottom of the screen is at eye-level; plus, there may be multiple tiers of seating, and those different levels must be accounted for.  I advise marking the wall with tape to gauge best where those points fall if some adjusting needs to be considered.

 

Most of what has been covered here is laid out in greater, yet understandable, detail by the fantastic folks at rtings.com. Click on the link to see what they address.

https://www.rtings.com/tv/reviews/by-size/size-to-distance-relationship

 

Following these guides will help you in getting the right screen size for your space. With some crucial adjustments to front panel controls, or opting instead for professional calibration of your display (topics for a later post), you will be ready to enter new worlds of entertainment through the window-like portal of your TV or screen.

 

Part of the escape and exhilaration always comes from opening that door.

 

 

 

 

The Subwoofer


“Got God on the drums and the Devil on the bass”

Why a subwoofer? The whole function of that big box is to reproduce low frequencies that your other speakers may not be able to reproduce well. In a digital audio system, the recordings also use that bass-only channel for unique information. In movies, it can be the speaker that reproduces all the rumble that excites and envelopes. In music, it can be the speaker that reproduces the low notes that stir you. It is a vital component in many modern audio systems.

 

Often, in conversations with others about their entertainment systems, a common complaint is the subwoofer volume is always needing adjustment – turned up when the bass is insufficient, and back down when it’s too much. It’s frustrating having to make these volume changes all the time.

 

There are likely two very simple reasons for this: firstly, the subwoofer level has not been set properly (modern receivers employ audio correction software and a microphone that can balance the level of the subwoofer and the other speakers together based on seating positions), or, more importantly, as this can even affect even the microphone correction accuracy, the subwoofer is sitting in the wrong location in the room.

 

The acoustic correction software built-in to most modern A/V receivers can be quite advanced, but not enough to ever compensate for poor subwoofer placement.

 

To understand why this is the case, there are some things to be aware of regarding how low-level frequencies behave in a room. In most cases, the subwoofer is passing frequencies below 100 Hertz (Hz); these frequencies are omnidirectional, meaning you cannot tell where they are coming from (the sub does not need to be seen to do its job). The issue, though, is that these frequency waves are quite large (most bass we hear in movies is around 30-50 Hz, and a 40 Hz wave, for example, is 28 feet long). If you want a visual correlation about how these waves might interact in a room, think about splashing around in a pool or bathtub: where waves combine with one another, we produce bigger peaks, and where they drop off together, we get troughs. These troughs in the audio world are null spots where we don’t get the impact of the bass frequencies. The nodes in the room where bass waves combine makes bass louder. Unlike the randomness of splashing in the tub, audio waves in a room can exhibit fixed trough/peak locations. Based on the sub location and your seating position, you may find yourself sitting in one of those nulls, getting no decent bass, or on a frequency’s peak, emphasizing certain bass frequencies over all others in your system. When you make volume adjustments, you’re not fixing the underlying issue, you’re just increasing or reducing how you hear the effect.

 

So the question now arises: How do I determine where to put the subwoofer to mitigate these issues?

 

There are a couple basic steps to follow to try to improve bass. When in doubt, the best location for a subwoofer is a corner in the room. Low frequencies are enhanced by barriers, and a corner provides three immediate barriers, loading the bass response and often exciting bass interactions in the room (there are sub designs where this might not work – ported subwoofers need to have the port away from the walls to allow proper tuning and air flow). The second key rule is to never have your seating against a wall. Some bass frequencies will peak at the wall, adding to one another, overdriving your perception of the bass, drowning out other sounds. This can be difficult to accomplish in smaller rooms, but moving your couch or seats away from the wall will give you a better chance of sitting in a location where bass frequencies are more evenly distributed. Once you’ve satisfied the above two steps, recalibrate the speaker levels (rerun the mic audio correction in your receiver).

 

My sub just chillin’ on the couch waiting for popcorn and a Coke.

The corner may not be the ideal acoustic location. You may want to refine the sub placement and this next trick is where magic and science meet. You’ll need a long subwoofer cable (thanks to the internet, these can be inexpensive), a test tone generator (most A/V receivers can generate this tone, or you can download handy apps like THX Tune-Up on your phone), and an SPL meter (apps for phones available). Place the subwoofer on the couch, at the primary listening position. Run the test signal to the sub and walk the room with the SPL meter. When you get to the spot in the room where the meter peaks, you have just found two nodes in the room that cooperate. Place a piece of tape to mark that spot in the room. Now move the sub to another listening position and test again. Mark this new spot with tape. Repeat for a third and maybe fourth listening position, and mark those spots. You should be able to gauge an average location from those tape markings for the sub placement. Once the sub is placed, rerun the audio mic correction to balance the full speaker system.

 

The advanced approach is to have audio RTA (real-time analysis) done for the room and speakers, to determine the speaker placement, levels, and sub placement that will produce the most even overall frequency response. Often, this type of analysis can be done in conjunction with DSP equalization to correct more aggressively (certain higher-end receivers offer this type of equalizing in their audio correction scheme).

 

The ideal scenario is to design a room from scratch, where Dimensional Analysis can be used to calculate the dimensions of the room that are best suited for low frequencies, and then employing any of the above steps will yield the best results possible for bass response.

 

Now you’re armed with some tools to help you with that pesky subwoofer. Good luck, and good listening!

 

A Simple Setting


“Something’s Not Right.”

 

The idea of a movie theater level experience at home is exciting. The chance to get gloriously better sound from our movies, and even our normal TV viewing is something many of us want. Access to the processors and speakers and other hardware necessary for us as consumers to realize this has gotten very easy and affordable over the last several decades. So now we go out, we buy the systems, we put it all together, we fire up our Blu-Ray player, drop in the disc and press play. And the magic happens.

 

Or perhaps it doesn’t.

 

Yes, you got sound. Yes, the speakers are all playing. Yes, it sounds so much better than the television speakers.

 

But there is a strong possibility that you are not actually hearing the soundtrack as it was intended. There is a very strong possibility you have NEVER heard your system do what you bought it to do; it’s the unfortunate truth about factory settings. The best sound system really isn’t as plug-and-play as we’ve been led to believe. I could talk at length about speaker placement, seating locations, speaker delays and levels, audio calibration, sound processing settings; all of those things are crucial to sound reproduction, but what I’m addressing is something far simpler.

 

Let’s just cover sound signals very briefly. When stereo sound evolved into stereo surround (Dolby Stereo, or what we referred to in home systems as Dolby Surround), the soundtrack had to be able to play on both older stereo-only systems as well as surround systems. The surround information was matrixed into the stereo track (left and right channels) so that all the sound information played through stereo speakers, but could be decoded and steered to play back in surround speaker systems. With our cable and satellite boxes and Hi-Fi VCRs, that information was passed on with the red/white (L/R) analog connections. Some set-top boxes (and yes, Laser Disc) offered a digital style output besides the analog ones. The digital signal was transmitted in a PCM format (same as on a CD), cleaner, less susceptible to noise and interference. Then, in 1992, Dolby introduced a massive leap in theater sound, the multi-channel stereo recording, known as Dolby Digital. Thanks to first Laser Disc, and then in 1996 to the launch of DVD, the full glory of 5.1 surround sound made it into homes.

 

The issue is those pesky factory settings I mentioned; you may have missed one setting in your player that governs whether you’ve actually been sending the proper sound signal to your processor. This setting is a game-changer; and yet, I rarely, if ever, hear it being discussed anywhere.

 

Here’s the thing. Every digital surround encoded signal still has to be backward compatible to stereo-only or older matrixed surround systems. In nearly every single disc player and set-top box, there is a setting that dictates which digital signal is being transmitted. If your source device is set to the PCM digital signal, you have NEVER heard discrete, multi-channel Dolby Digital surround sound. NEVER.

 

If you own, for example, any Sony video disc player (even any iteration of Playstation), and you did not manually go into the menu and change the default setting from PCM to Bitstream (or Dolby Digital), then you have only ever heard the old stereo audio track. Every Sony player is set to PCM out-of-the-box –  for over twenty years! Even on more modern players, the HDMI output may be set to run a downmix audio track compatible with older systems, which defeats the incredible Dolby and DTS HD master tracks on Blu-Rays and 4k discs.

 

It behooves you to check the settings in your set-top box or disc player and even the default audio format being output by your smart TV to your surround system to be sure you are sending/receiving the full digital signal. Over and over and over again, I would find myself correcting this setting on existing customer systems where I had been called in to update hardware or to help improve their systems. That one, simple change offers a vastly different performance. The soundstage is brighter, clearer, more enveloping, more exciting. That one change delivers the type of experience you thought you had purchased.

 

One simple setting. 

 

Now go check for yourself. Enjoy!

 

the experience


“Is the Water Running?”

Watching movies has long been an event for our family. My love of movies and cinema has passed on to my children – we regularly go to the cinema and watch movies at home – it’s always been a fun time to set aside, to engage and share in a common experience.

 

My children have all grown up with fairly state-of the-art surround systems in the home. They often accompanied me on robust home theater projects and enjoyed being my test audience. When they were little, they hated going to friends’ houses to watch movies, felt they were sub-par efforts. I raised snobs, apparently. One late night, my daughter, then in college, called me, frantic, “Dad? How the hell do you shut of the motion setting on a TV? I’m at a friend’s watching a movie and it looks terrible. I can’t watch it. I made them pause the movie so I could call you.” I laughed and walked her through what to look for to disable it. After getting off the phone, my wife asked what the call was about and as I explained, she looked crossly at me for a moment, then cracked a smirk. “Your children.”

 

My wife, God bless her, despite her limitless love for me, tunes me out when I talk about A/V stuff. She has tolerated my endless pursuit of audio perfection over the years, and although she has enjoyed what we have at home, she’s never been over-the-moon about any of it. She has, though, been very supportive of my desire to get involved in A/V again, recognizing how my knowledge, skill, and passion can benefit others..

 

With her blessing, earlier this year, in preparation for launching Ekho Home Theater Group, I upgraded our family room to an aggressive Dolby Atmos 3.1.2 system, ideally suited for rooms where surround sound is not possible, feasible, or even practical. After a very solid day spent installing hardware, integrating and programming, and breaking in the speakers with some energetic music, my children voted to inaugurate the system with Master and Commander: The Far Side of the World, arguably one of the finest surround mixes ever produced, winner of the Academy Award for Best Sound Editing, and deservedly so. The track on the Blu-ray, however, is a standard 5.1 mix, not Dolby Atmos encoded, so this choice would prove a test of the system’s ability to virtualize with a more common soundtrack.

 

I can’t possibly cover every amazing audio event during our screening. For that, you just need to come over – we’ll watch it together. I will tell you that the soundstage was massive; the front of the room was a full left-to-right, floor-to-ceiling wall of sound that realized itself fully three-dimensionally into the space. Every wave, every creak of the ship and ropes, every footfall from the sailors walking on deck rang true. At one point in the movie, after a major ship-to-ship cannon battle, as the sailors hurried to stop the flooding below deck, my wife turns to me and quietly asks, “Is the water running?” It was a fair question. The sound of rushing water was so enveloping and convincing, and beneath it a tone not unlike the sound one hears in our house when a bath is being run upstairs, or someone is doing laundry. I turned to her, smiled, and whispered back, “No, dear, that’s the movie.” And her eyes lit up. And in that moment, I realized she finally understood what I had been trying to do for so many years. 

 

We have been rewatching movies we know well, all because every one of them now feels new, different, better. My children and I, and even my wife, get excited every time some little nuance in the soundtrack grabs our attention. We watch everything on this system, TV, streaming, and Blu-rays. We all play music on it. CDs sound cleaner and more lifelike. We’ve even bought a record player and started listening to vinyl again. The experience is everything.