two digital amps pass THX Ultra2 specs

[Andrew Pratt]

Two Digital Amplifiers Achieve the THX Ultra2 Criteria for Audio/Video Receivers
SAN RAFAEL, Calif.* December 14, 2004 -* THX Ltd., the leading provider of technologies, certification programs and quality assurance standards for the entertainment industry, today announced that two digital amplifiers have successfully met the performance criteria for use with THX Ultra2 Certified audio-video receivers. D2Audio and ICEpower are the first companies to design digital amps capable of achieving the THX Ultra2 amplification requirements. Each amplifier has distinct performance characteristics and is unique in its design approach to solve key technical and performance requirements of digital amplifiers.



“THX has made it a priority to partner with leading technology developers to analyze and qualify new technologies and components for integration into THX Certified products,” said Laurie Fincham, vice president of engineering at THX. ³This type of work provides our licensees with a means to improve product time-to-market by verifying components in advance that can be used to meet THX Certification standards. As the THX Certification program expands, we will continue to focus on researching and validating the best possible technology solutions for our partners.²



Digital amplifier technology can provide several key benefits to manufacturers of audio-video receivers, including slimmer designs for reducing overall system size and customizable playback features. However, until now, most digital amps could not deliver THX Ultra2 compatible performance. The THX engineering team worked closely with many digital amplifier manufacturers for several years, conducting exhaustive testing until the THX specifications were finally met by D2Audio and ICEpower. Their digital amps are now available for integration with THX Ultra2 Certified receivers, providing THX¹s partners the flexibility to choose from a variety of analog and digital amp components for next-generation home audio products. Each company, along with the market, will determine the applications these two digital amps are best suited to address.



“This is a true milestone for digital amplifier technology,” said Skip Taylor, chief technology officer at D2Audio. “Reaching the performance levels required for THX Ultra2 Certified receivers moves D2Audio¹s digital amplifiers into a new class of quality, illustrates the ability to break down the historic barriers for this new technology, and opens the door for integrating digital amp components into more high-end audio products.”



“THX dedicated a considerable amount of time and resources to evaluate our technology and provide insight into achieving the amplification requirements for the THX Ultra2 Certified receivers,” said Karsten Nielsen, founder and chief technology officer from ICEpower. “The result is a digital amplifier that will not only improve home entertainment systems¹ performance levels, but will also expedite the CE industry¹s transition from analog to digital amplifier components.”



ABOUT THX ULTRA2

THX Ultra2 Certified audio-video receivers are designed by manufacturers to meet or exceed the THX specifications for presentation excellence. THX Ultra2 Certified products accurately translate multi-channel audio content movies, music and games‹to home theater environments, and incorporate THX listening modes and reference levels for bass management, distortion and signal noise. D2Audio and ICEpower meet the amplification performance requirements to have their companies¹ components in THX Ultra2 amplified products.



ABOUT THX LTD.

THX Ltd. provides technologies and services for optimizing the production and playback of entertainment content in the professional and consumer markets. The company¹s certification programs and technologies deliver the ultimate entertainment experience, providing superior playback of movies, music and games, and improving the interoperability of entertainment products and applications. Today, thousands of commercial cinemas, post-production studios, home entertainment products, DVDs and games have been designed and certified by THX. Founded in 1983, THX is headquartered in San Rafael, Calif. Its Digital Works office, offering quality assurance, DVD mastering and post-production services, is based in Burbank. For more information, visit www.thx.com.

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[chrispy35]

Can anyone provide the THX Ultra2 requirements for amps (or a link to them)? I'm curious as to what is so hard for a digital amp to accomplish. The THX webpage is quite vague.

[Andrew Pratt]

Can anyone provide the THX Ultra2 requirements for amps

Step 1... write check for $$$$$$$$ to Lucas.
Step 2... see step 1

Actually I'm not sure what the requirements are but all I've ever seen was a wattage rating that it must be able to produce all channels driven I think. Its been some time though since I've seen any reference to the actual values.

[Burke Strickland]

The exact THX standards are proprietary, meaning you have to pay a fee and sign a nondisclosure agreement before you have access to them. Certification of equipment to those standards is a process that includes paying the licensing fee in addition to having the equipment tested for performance compliance.

Those of us who have not met those requirements only get vague descriptions of what they cover, along with the assurance that equipment meeting THX standards have shown evidence of performance adequate to the task when playing movie soundtracks.

That doesn't necessarily mean that other equipment isn't just as adequate, but it does mean the other manufacturers have not gone through the certification process (e.g., haven't paid the fees / had their equipment tested.). Of course it could also mean that the equipment isn't capable of meeting the standards, and I imagine that's what Lucas and company would like for everyone to believe about non-THX certified equipment. :>)

Burke

PS -- I'm guessing that digital amps would have to meet the same performance criteria as analog amps to be certified for a given level such as THX Ultra 2. The key point is that the standards have been achieved, not how they were achieved.

[chrispy35]

I figured as much about protecting their IP. I wonder if it's just that these are the first two digital amps to apply for certification so everyone figures a press release is due. We're totally at their mercy as to how hard it was for these amps to pass (maybe they passed on their first try).

I would guess that if the requirement is to drive X channels at rated power for T seconds/minutes/whatever, the main problems to be encountered during certification would be power supply and thermal issues, not circuit topology.

Can anyone think of any measure of amp performance where a digital amp has some architectural deficiency compared to an analog amp?

[JonMarsh]

I figured as much about protecting their IP. I wonder if it's just that these are the first two digital amps to apply for certification so everyone figures a press release is due. We're totally at their mercy as to how hard it was for these amps to pass (maybe they passed on their first try).

I would guess that if the requirement is to drive X channels at rated power for T seconds/minutes/whatever, the main problems to be encountered during certification would be power supply and thermal issues, not circuit topology.

Can anyone think of any measure of amp performance where a digital amp has some architectural deficiency compared to an analog amp?

Output noise- they have varying amounts of conducted RFI on the speaker leads. This is true of conventional PWM designs, especially so of the Sharp DSD design. Overall S/N is often not as high, unless it's a very high power design. THD at high frequencies tends to be not so good. Slew rate for audio signals can be problematic- is usually a tradeoff between that and output noise.

Note, I have some experience designing and building class D amps.

BTW, the ICEPOWER modules are probably (IMO) the highest performance switching amplifier for widerange applications on the market. I'm not surprised theyr'e one of the ones qualified. They're primarily at the high end, now, but have plans to move down market into more midrange applications. Should be interesting to watch...

~Jon