There are many things I know nothing about–car repair, home repair (in fact, repairing anything that isn’t computer-related or audio video electronics), mixing drinks, baseball statistics, thermodynamics, how Republicans can actually believe we have a ‘free market system’–but something I DO know something about is home theater equipment and the technology required to produce quality audio and video.

So, if you’re in the market for a home theater system in general, or an AV receiver in particular, here a few things you should make a priority in your purchasing decision.

1. HDMI 1.3a: HDMI is an interface that allows you to connect a source component, like a DVD player, to a Receiver, preamp-processor (what used to, in the stereo days, be called a ‘preamp’, but now is nicknamed ‘pre-pro’), or high-definition display, and send an uncompressed, encrypted video and audio signal through one cable.

So, with HDMI 1.3a, you need one cable to send audio and video of the highest quality to your display.  Unlike earlier versions of HDMI, this version expands the range of displayable colors to billions (instead of 16.7 million), and includes support for high-definition audio standards.

Now if you get an Audio-Video Receiver with multiple HDMI 1.3a inputs, you can hook in an upconverting DVD player, to play your standard-definition DVDs back at high-definition resolutions (1920 x1080p or 1280 x 720p) your Blu-ray DVD player, to playback your high-definition DVDs, your XBox-360 or Playstation 3 to display your games in Hi-Def (of course real men play Xbox 360 and not Playstation 3–you know who you are), and your home theater PC video output (to surf the web, watch downloaded videos, etc.).  That’s 4 inputs right there.  You’re probably thinking "I don’t need 4 HDMI inputs–why, I don’t even need 2!"

Well, here’s the thing.  When it comes to electronics, you always need more of something than you think.  Get a receiver with at least 3 HDMI 1.3a inputs and you won’t be sorry.

The Sony ES line, Denon x808 line, and Onkyo AV receiver lines all have 3 or more HDMI inputs.

2. Automatic room equalization:  If you get your home theater room, or room where you are going to watch movies and listen to music, set up with 5.1 speaker surround sound (you really should go for 7.1 surround–what’re two extra speakers to a Captain of Industry like you, anyway?), you need to calibrate your speakers to optimal playback based on where you are listening.  Audyssey’s equalization system, available in many lines of AV receivers, including some of the ones I mentioned above, provides you with a microphone which is connected to your receiver. You place the mike where you are most likely sit and watch a movie, and the receiver then calibrates the speakers and determines how much delay each channel should have, etc. It is surprisingly accurate and makes a HUGE difference in the audio experience.

Different vendors have or license different solutions for this, but Audyssey’s is considered the best or one of  the best.

3. Burr-brown or Wolfson DACs (Digital-to-Analog Converters):  Burr-brown, now owned by Texas Instruments, along with Wolfson, make the best audio converters around.  Why is this important you might ask? Because a good DAC can make the difference between a great audio experience and a mediocre one.  A good DAC has better error correction, higher bit resolution, and better processing of audio signals.  Look for 20-bit Burr-Brown DACs wherever fine DACs are sold–they actually come in PrePros (’Preamp Processor) and AV Receivers.  You want to make sure there is one of these DACs for each audio channel (so, 7 channels = 7 Burr-Brown DACs).

4. Multimedia/video Procesing Engine:  ‘What’, do you say, ‘is a video processing engine, and why should I care?’  Well, as you increasingly pump billions of bits from your high-definition source material (Blu-ray, game console, video camera, Digital SLR, etc.) to your high-resolution display, you want to make sure that all of it is converted from whatever resolution (720×480i, 720×480p, 1280×720p, 1920×1080i) it started in to your output resolution which is hopefully, for your sake, 1920×1080p.  What do the ‘p’ and ‘i’ stand for? P = progressive scan, I = interlaced.  I don’t have the desire to explain what those are and why they are different, and will let you google that; I"m sure some kind soul has written about it at Wikipedia.

As you’re sending all of this digital data through–you guessed it–your HDMI cables to your HDMI-enabled AV Receiver, your AV receiver has to process these signals, remove noise if any exists, and convert the output to 1920×1080p if it isn’t already 1080p, and then send it on its way to your HD flat panel display.  This whole process is called ‘transcoding, upconverting, and pass-through’ depending upon which activity you are talking about specifically.  Just as you benefit from Burr-Brown or Wolfson DACs for processing your audio, you benefit from Silicon Optix’ Reon or Realta HQV or Gennum VXP chips or  in your PrePro or AV Receiver.  These chips do a better job of processing your video–in essence a graphics card for your AV receiver instead of for your computer.

In fact, it’s helpful to think of your AV receiver as a computer that looks like a stereo component.  That’s really what it is, except that–unlike your regular PC or Mac–this computer can’t be programmed to load any software you like.  It can only be programmed within the very limited domain of audio and video settings and networking.

That’s all for now. I’ll talk next time about which home theater components I would recommend at some different price points, and why you owe it to yourself to have a home theatre PC.