Adventures in Home Theater Calibration

One man's attempt to calibrate his high-definition home entertainment system.

May. 28, 2008 — by .(JavaScript must be enabled to view this email address)

It’s no secret that when you go to your local big-box retailer to look at HDTVs, the sets on display are brighter than the sun. Manufacturers want the brightest set on the shelf to draw you to their TV. When you get that new set home, you’re not likely to find your picture looking much better.

That’s why it’s so great that calibration DVDs exist, allowing you to properly set your picture settings to get the most out of your TV. There are several different options available when it comes to the DVDs, but two pop into most people’s heads: The Avia Guide to Home Theater, and Digital Video Essentials.

Avia is a great product - and the first calibration disc I owned. When it comes to setting up your HD signal, however, the newly released Digital Video Essentials HD Basics from Joe Kane Productions is your best option. It’s the first product on the general consumer market specifically designed for Blu-ray and HD DVD, allowing you the chance to calibrate your HD signal using HD material. Avia has a HD release listed as “Coming Soon” on its web site.

Having recently received the HD DVD version of DVE, I’m going to take you through the process of calibrating my setup. First a look at what I have in my living room:

My Setup:
50-inch Samsung HLR-5067 720P DLP
Xbox 360 HD DVD player hooked up via component video
Yamaha HTR 5750 5.1 channel receiver
Klipsch 5.1 channel Quintett II speakers
Klipsch KSW10 Subwoofer

My TV was last calibrated roughly two years ago after purchase. I performed that calibration using the original Avia disc. After two years of minor tweaks it was obvious a recalibration was in order. In the spirit of full disclosure, I’ll show you my before and after settings. Note that I’ll be using only the menu options available via the TV’s main menu and not the set’s service menu. Almost all TVs have a service menu accessible only to qualified technicians due to the potential for permanent damage.

Current Settings

TV
Contrast – 89
Brightness – 54
Sharpness – 39
Color – 54
Color tone – Normal

Receiver
Front left - +4
Center - +2
Front right - +2
Rear right - +4
Rear left - +4
Speaker settings - All set to “small”
Subwoofer - +4
Crossover - 80Hz
Phase – Normal

The Disc Itself
Since this isn’t a review of DVE, I won’t spend a ton of time on the disc itself. Suffice to say there’s a lot of content, more than 100 individual listings in the disc’s index, with more than half of that dedicated to test material. Along with the test patterns, there are a couple hours of information on how HD signals are created, calibrated and adjusted at the source. You can certainly skip the non-test material and get right to calibrating your set, but the background info is very informative and goes a long way to help you understand why your monitor behaves the way it does. The introduction to HD section was of particular interest to me. 

Video Tests
I made several discoveries about my TV while working my way through the video test patterns. First, it doesn’t accurately display below-black color in the PLUGE with Gray Scale pattern, as systems standards say it should. Also, I found that my set will properly calibrate blue and red using the color filters included with the disc, but can’t come close to getting green right. According to the disc, these are common problems. Finally, I determined that my set is likely using the standard definition decoder (ITU 601 SMPTE 170M to be exact) for setting color instead of the HD decoder (ITU 709 SMPTE 296M), another very common issue in some HDTVs.

After about an hour of working with the video test patterns, I made pretty good progress. Here’s how things changed, my old settings first:

Contrast - 89 to 92
Brightness - 54 to 58
Sharpness - 39 to 11
Color - 54 to 60

You can see that my sharpness setting number dropped by more than a third. According to the disc’s HD Video Calibration section, this control is actually a holdover from the early days of color TV. In most cases, this control doesn’t need to be active for HD signals. Sure enough, using the Overscan test pattern, I was able to see I had mine set way too high.

My display performed miserably in the Overscan test (screen area). When looking at that pattern I can see I’m losing the bottom five percent of the picture, the left three percent, the top two percent and the right two percent. I also learned that my picture is rotated ever so slightly clockwise. Unfortunately I can’t fix any of the Overscan issues without getting into the TV’s service menu. I did buy an extended warranty with my TV, so hopefully I can get some of these issues resolved with a technician, and maybe convince him to show me the service menu while he’s at it.

Once I finished with the calibration, I went to the disc’s demo material, which is broken up into both 720p and 1080p material filmed at both 24 and 60 frames per second. My set’s limits showed themselves again when trying to process the 24FPS material using a 3:2 pulldown. Make sure to watch the 1080p material with Joe Kane’s narration even if you have a 720p set, as he does a great job of explaining what to look for in the demo material.

An unexpected benefit of my efforts was how much better my Comcast HD signal looked when I used these same settings on that connection.

Audio Tests
Calibrating the audio proved to be slightly less time consuming, and having someone help you would make it even quicker. The majority of the tests on the disc are video tests, but it includes everything you need to properly calibrate your audio. Be sure to have a sound pressure level meter with you when performing these tests.

Using the Band Limited Pink Noise Multi-Channel Levels and Balance (whew) test signal along with my SPL meter, I was able to get my receiver putting out 75dB at reference level on all my speakers. I flipped to my receiver’s built-in test tones just for comparison and found that they were about 2dB off from the disc’s tones and nowhere near as uniform, varying by as much as 2dB from tone to tone. Here are the results of my audio calibration, original settings first:

Front left - +4 to +2
Center - +2 to -1
Front right - +2 to -1
Rear right - +4 to -3
Rear left - +4 to 0
Subwoofer – Settings stayed the same

All told I spent about four hours with the disc. It was a great exercise and I’m getting renewed enjoyment out of my set now that the picture is back to looking its best. Certainly, hiring a professional to calibrate your discs to ISF standards will yield the best results, but for only the price of the disc and sound meter, you too can have your set looking its best.

Read more about home theater calibration on ElectronicHouse.com:
Calibrate Your Own Audio and Video
Get the Best Picture from Your New TV

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