Video and Audio Center Blog

Tuesday, February 10, 2015


The name "home theater" was coined as a direct affront to movie theaters as in, "You can watch at home with the same level of enjoyment as if you were going out to a movie theater. But the reality has always been about comfort and convenience: watching at home means watching what you want when you want. But in order to do that, a big TV with a good sound system is needed. That wasn't so easy to acquire back in the day, but with big screen TVs so reasonably priced, pretty much any room can become a "home theater" and be worthy of the name.

But like any technology that has grown in leaps and bounds, some misconceptions have taken root. These misconceptions about home theater can keep you from enjoying the best picture and sound possible. So lets put a stop to three misconceptions right now.

The brilliance of a HDMI cable is that it can transmit not just high-definition video but multichannel audio as well. This is both convenient (removing the need for separate audio/video cables) as well as practical (since the connection looks unlike others and just works via insertion/gravity rather than any locking mechanism). But while digital ensures that if the cables wiring is working a picture is seen, the requirements of bandwidth needs today require a high-speed cable. This makes inexpensive models less likely usable and so should be avoided. Additionally, the cost of a HDMI cable can be quantified by its construction how well it will hold up physically. This means that not all HDMI cables are the same, since the quality of how they are made affects their overall use over time. This can be especially true when greater lengths are needed.

There's no question that a surge protector will help protect electronic devices plugged into the AC line -- the power "grid" is undependable at best and even minor surges can be problematic to electronics depending on electrical power to operate. That includes power "spikes" too both can cause damage over time (and invisibly). But its also true that AC power is "dirty" and can negatively impact both video and audio by degrading the quality subtly. To avoid that, a power conditioner will come in handy. What this does is take the AC power and conform and adjust it so that whatever is plugged into it benefits from a stable and "clean" current. This can only improve on the video (i..e., the TV picture) and the audio (i.e., the amplifier, sound bar, etc.). Best part is that you plug your devices into the power conditioner and then forget about it -- other than making some adjustments to the conditioner itself, there's nothing else that needs to be done. And yes the power conditioner has surge protection too.

Its understandable that reading a manual laced with technical jargon can be annoying pretty much every amplifier (i.e., audio/video receiver) is full of this because theres so many options and adjustments that can be made. But unlike a sound bar, an amplifier can adjust the sound coming from multiple speakers so as to make them provide a balanced sound basically making the speakers work together. So adjusting the speakers to benefit the listening position makes complete sense if only it wasnt such an issue to have to adjust each individually. Thats where the manual comes in, since most amplifiers include a microphone that, placed at the listening position, works with the amplifier to automatically do the adjusting through a series of tones. Its fast and painless (unless you stay in the room while the tones blast out) and improves on the sound immensely. It should be done.

Having a home theater means that you want the best possible picture and sound that you can get. Eliminating the misconceptions that can keep you from having that is a simple but necessary step that is well worth doing.

Wednesday, February 04, 2015


There was a time when the TV ruled the living room, not because of how good the picture was, but more so because it was the only game in town. TVs were tube-based and on average 19" in size and color, well that was an expensive option over black and white. Besides, how many TV shows were in color anyway?

Flash forward 60+ years and 50, 60 and 70-inch TVs now rule. Filled with tech that past TV viewers never dreamed of, one thing is still lacking. Sound. Hence the appearance of the home theater. Savvy TV viewers figured out early on that the audio coming from the TV had limitations. So the TV viewer decided to get full-on speakers and connect them to the TV. This led to multiple speakers able to provide surround sound, rear surround and much more -- thanks to mature technologies like Dolby Digital and emerging technologies like Dolby Atmos.

Arranged around a room, a set of speakers makes what IS a home theater, complimenting the TV's visual might with awesome sound. But to drive the speakers, an amplifier is needed. It too has evolved, becoming the  AV (audio/video) receiver for taking and controlling video so that it can be sent to the TV. AV receivers are impressive to look at; they're usually a jet or matt black with big knobs and multitudes of tabs and buttons controlling a vast array of audio and video features. Even if all you ever use is the remote, the number of choices of sound quality results can seem staggering. Especially if you're less familiar with what makes for good audio. So with that in mind, lets blow away the smoke hiding the basics of what makes for a good AV receiver without having to resort of charts, diagrams or sound theory. It's what you hear that counts.

An AV receiver gives the amount of power it possesses in watts; for example 150 watts. The more power, the louder the volume can become, but more importantly, the louder it can be before it starts to distort. So a realistic way to look at this might be to say that a 200 watt AV receiver @ 70% volume will sound "cleaner" than a 125 watt receiver turned all the way up. But another thing to keep in mind is RMS --  a number noting the average power output of the speaker over a period of time. For many this is a more accurate way to look at the amount of "oomph" the receiver can turn out to the speakers its in the specifications so all that is needed is to look.

An amplifier must supply power to the total number of speakers connected to it evenly. Speakers are rated for their power requirements and so if a speaker with a nominal impedance of 8 ohms is rated at 100 watts, then the amp needs to be rated at about double that -- in this case that would be up to 200 watts per channel. So when getting a receiver for the first time or in tandem with speakers, be sure to check the speakers capabilities in this area first, then make your decision as to the amplifier with this in mind.

AV receivers provide for multiple speakers to be attached to them. For a stereo receiver, its just two but for multichannel capable receivers, it can be many (for example, a 5.1 or 7.1 or a 9.2 system in which the 1 or 2 represents a self-powered subwoofer attached). The receiver can have more speaker capability than the speakers in the home theater as you can always add more speakers.

AV receivers offer a wide array of audio modification technologies, from auto calibrating all of the speakers using a microphone to turning off the video circuitry so that the music being played is more pure. Other examples include being able to act as a video switcher and handling 3D video as well as passing through 4K high resolution. More recently Bluetooth has been added and new audio tech such as Dolby Atmos. The main issue here is that this is built into the hardware and so must be present when you get the receiver it cant be updated at a later time.

An AV receiver was once a major investment in terms of cost and commitment, but now they have become more affordable even as the brand names like Denon and Sony and others have maintained their level of excellence for sound reproduction. Pair an AV receiver with a set of speakers and a big TV and your home theater will be a place where many happy hours of listening to music and watching TV and movies will be spent.