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Understanding the Differences between HDMI Versions

HDMI has changed versions so many times it's been hard to keep up for most people. We've talked about the versions as part of other articles and documents, but it seemed fitting that we'd formulate and maintain a definitive document outlining the changes in a straightforward and easy-to-digest manner for all concerned. Hopefully this article helps you understand the format differences and aids in your ability to discern what features are important to you as you shop for HDMI-equipped products.

We are always preaching the more subs the better in a home theater system. So now that you've decided to purchase two subs, its time to show you how to correctly connect them up to ensure you achieve the maximum benefits of a multi sub system. Following the guidelines set forth in this article will help you integrate a multi-subwoofer system into your home theater. If done properly, using two or more subs will yield significantly better and smoother bass response for all of the seats in your theater room.

Recently Published Articles

Tech Article: Going to 7.1-Channel Surround Sound
by Alan Lofft — last modified July 03, 2009 19:03

Almost everyone loves surround sound, (except for an eccentric actor whom I know who actually prefers mono!) and what’s not to love? Our ears are on each side of our head, canted forward, but we hear sounds from every direction with almost equal precision. For that reason multi-channel sound reproduction is intrinsically more realistic and believable. But how many surround speakers are required to present a plausible illusion of the real thing?

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Tech Article: Listening Room Acoustics: Room Modes & Standing Waves Part I
by Michel Leduc — last modified July 01, 2009 06:51

Room modes cause standing waves that can cause three acoustical problems: a level boost at some frequencies, an extent of the duration of sound at those same frequencies (resonance) and some profound dips at other frequencies. This article explores methods of reducing the problems of standing waves in your home theater room and also works real world examples for greater clarity. Don’t settle for acoustical compromises. Learn the facts, and arm yourself with the right tools to enhance your movie watching and music listening experiences.

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Tech Article: Audyssey DSX 10.2 Surround Sound Overview
by Paul Apollonio — last modified June 29, 2009 10:41

Audyssey as a company is sort of a brain trust that creates and licenses signal processing solutions. They employ the sciences of psychoacoustics, acoustics, signal processing and use highly complex mathematical algorithms to put those Mega Flop DSP chips to work to do dynamic equalization and derive extra channels for surround sound.

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Tech Article: The Crossover - Brain of your Loudspeaker System
by Paul Apollonio — last modified June 09, 2009 18:28

Have you ever wondered how the tweeter and woofer have their responses combined in a speaker system, or what the crossover network is and how it works? This article sheds some light on the least seen and perhaps most undervalued part of the speaker system, the crossover network. While passive crossover components and materials and construction have changed over time, the underlying theory and practice has not. In the real world, capacitors, inductors and resistors exhibit behavior which is neither ideal or perfect. In this article, we considered the importance of real loudspeaker impedance, and how it acts as a monkey wrench to complicate and frustrate the function of constant resistance type crossover networks.

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Tech Article: Bass Trapping Ideas for Non-Ideal Spaces
by Jeff Hedback — last modified May 27, 2009 08:23

Bass traps control low frequency issues in rooms. Simply, they are the single most effective investment toward a quality audio experience that is rarely made by the home theater enthusiast. The information contained within this article may not allow you to unleash your own plan for optimal bass trapping, but it may point you towards that result. Proper bass trapping is a 100% guaranteed investment and is worth a close look for those serious about achieving the best bass response their home theater systems have to offer.

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Editorial: How a Class D "Digital" Amplifier Works
by Alan Lofft — last modified May 07, 2009 20:56

Ever wonder how an amplifier works at a very fundamental level? Alan Lofft, Resident Expert of Axiom Audio takes us on a tour of traditional linear amplifiers as well as the newer more sleek Class D designs. Various types of Class D design approaches are discussed including feedback topologies and their implications on audio performance and efficiency. The similarities and differences of traditional Class D amplifiers compared to Axioms new A1400-8 multi channel amplifier is reviewed. Learn what makes these amplifiers tick and why it’s cool in more ways than one to get your hands on the future of high end audio amplification that is powerful, efficient, and lightweight compared to their analog predecessors.

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Editorial: Attack of the Clone Amplifiers
by Gene DellaSala — last modified April 28, 2009 18:16

It’s been a few years since our controversial release of “Attack of the Clone Processors” and we felt it was time for a sequel to our blockbuster hit editorial. Engineering a product from the ground up, especially one as complex as a switching amp, takes time and money with the end result often not being as good or cost effective as what can be bought off the shelf like these ICE modules from Bang & Olufsen. I can count the number of manufacturers producing their very own Class D designs and still have a finger left to point at all the copycats. Overall this seems to be a good design approach for manufacturers unwilling or unable to do their own developmental work if cost and full disclosure of performance is kept in check. It’s up to you the consumer to decide if paying a premium price for name brand, exotic accessory parts and cosmetics is worth the investment. Just don’t let anyone tell you that regardless of price, you are buying anything other than a clone amplifier, albeit a reasonably well engineered one.

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Pro Review: THX Video Calibration Training Class Review
by Tom Andry — last modified April 28, 2009 10:00

Calibration of displays is something that not many consumers know much about. Their expectation is that they buy a display, take it home, and plug it in. At this point they are done - or so they think. The next thing you know, they are telling their friends that HD isn't all that great and they never should have spent all that money. Is it true? Not by a long shot.

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Editorial: The Truth About Amplifier Power Ratings
by Rod Elliot — last modified April 27, 2009 19:06

Ever wonder why the boom box you bought at Best Buy has a higher power rating than your dedicated two-channel power amplifier? Amplifier power ratings are usually honest in Hi-Fi equipment, but become very silly when it comes to the 'mass market' systems and even some of the latest Class D amplifier offerings. Few amps have a dynamic headroom of better than 1 or 2dB, and the greater the headroom, usually the cheaper the power supply for the rated power. This article explores the history of power ratings for consumer audio and also busts the myth about 'RMS' power.

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Tech Article: Trading SPL for Extension in Subwoofers - A Current Trend?
by Paul Apollonio — last modified April 20, 2009 19:14

More often than not consumers are swayed by a single parameter in a products specifications to judge its true performance. Lately it’s quite a popular trend on the forums of people critiquing a subwoofers performance by a simple metric; its -3dB point or how low the subwoofer can go in frequency before its sound output rolls off. This article will explore the trade offs associated with tuning a vented subwoofer system for the lowest achievable frequency output and demonstrate a balance between real usable extension and efficiency for achieving the best performance given a particular driver size and box enclosure. When doing comparisons of subwoofers by looking at specifications, remember that published specifications are almost always static measurements, and usually only reflect what a speaker does at low drive levels, where speakers tend to be linear and well behaved. This is why judging a subwoofers performance by a spec sheet or singular measurement metric is misleading and often dangerous when trying to determine the better product.

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Tech Article: How Does Listening Room Acoustics Affect Sound Quality? — by Michel Leduc — last modified April 15, 2009 06:43

Tech Article: Trading Amplifier Quality for Features – A New Trend with A/V Receivers? — by Gene DellaSala — last modified May 04, 2009 10:12

Tech Article: Crimping & Soldering - Keys to Connection Performance and Longevity — by Thomas Steves — last modified March 09, 2009 18:42

Tech Article: What Do HDMI Spec Versions (1.2, 1.3, 1.3a, etc) Mean For Cable Choice? — by Kurt Denke — last modified March 05, 2009 06:02

Tech Article: Do I Need 120 Hertz HDMI Cables? — by Kurt Denke — last modified December 31, 2008 04:39

Tech Article: Myth vs Reality – Putting Cat5E-Based A/V Structured Wiring In Its Place — by Joseph D. Cornwall — last modified October 06, 2008 08:46

Tech Article: Loudspeakers & Power Ratings Part III: The Test Results — by Paul Apollonio — last modified September 25, 2008 05:24

Editorial: 10 Things about Audio Amplifiers You've Always Wanted to Know — by Alan Lofft — last modified September 18, 2008 11:37

Tech Article: Flat Panel Trends - Thin is In and Speed Kills — by Clint DeBoer — last modified September 05, 2008 12:46

Tech Article: Upscaling is your Friend? — by Tom Andry — last modified September 05, 2008 12:30

Tech Article: Wireless HDMI Takes Flight — by Tom Andry — last modified September 05, 2008 11:41

Tech Article: Loudspeakers & Power Ratings: What's the Deal Part II? — by Paul Appolino — last modified August 31, 2008 09:10

Tech Article: Loudspeakers & Power Ratings: What's the Deal Part I? — by Paul Apollonio — last modified September 02, 2008 13:05

Tech Article: Long HDMI Cable Bench Tests - Monster Cable Shootout — by Clint DeBoer — last modified July 08, 2008 06:50

Tech Article: Sound Bars with Chip-Based Technology Bridge Gap — by Claus Neesgaard — last modified June 26, 2008 04:52

Tech Article: Pear Cable Redux: How to Combat Scam with Science — by David Waratuke — last modified May 13, 2008 08:43

Tech Article: Ask Dr. A! Too Many HDMI Outputs — by Clint DeBoer — last modified May 06, 2008 05:31

Editorial: THX Certified Display Program Interview — by Gene DellaSala — last modified May 07, 2008 12:45

Tech Article: No HDMI Output with Component Source — by Clint DeBoer — last modified April 25, 2008 06:04

Pro Review: Dayton Audio WT3 Woofer Tester Review — by Mark Sanfilipo — last modified April 17, 2008 19:07

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