Audio DesignLine: Class D Audio Amplifiers

The Audio DesignLine website has posted a series of Class D Audio Amplifier articles. These were written by Eric Gaalaas of Analog Devices and are based on his original article which was published in EE Times magazine. Some of the data used to show the performance of Class D amplifiers in these articles is based on technology from Analog Devices, like the AD1994 Class D amplifier. The 25W AD1994 doesn't necessarily meet the performance specifications of a high end home theater system, like the Class D amplifier modules from Hypex, ICEpower or ColdAmp, because it is designed primarily for applications like automotive audio, or integration with flat panel televisions. However, this series of articles does provide a fairly good overview of the technology.

The first article, Class D Audio Amplifiers: What, Why, and How, describes the different topologies of Class A, B and A/B linear amplifiers and their power dissipation characteristics. The main point here is the Class A amps dissipate a lot of power in the form of heat (in fact, more power is dissipated than is sent to the loudspeakers), but the sound quality is very good; Class B amps don't dissipate as much power, but the sound quality isn't very good; and, Class A/B, which is a hybrid of the two, dissipate less power than Class A and a little more than Class B, but also sounds much better than Class B.

The second installment, Class D Audio Amplifiers: What, Why, and How - Part 2, describes the basic architecture of a Class D amplifier and explains how they are much more efficient with regards to power dissipation. They mention how the output efficiency effects system design and that products with less efficient amplifier topologies sometimes use large, heavy heat sinks or fans to avoid over heating the components.

In the third article, Class D Audio Amplifiers: What, Why, and How - Part 3, the author talks about Class D amplifier terminology and compares single ended to differential designs.

The fourth article, Class D Audio Amplifiers: What, Why, and How - Part 4, describes some of the challenges with Class D technology and discusses techniques for improving sound quality by using feedback circuits.

In the fifth installment, Class D Audio Amplifiers: What, Why, and How - Part 5, he discusses the modulation techniques used to convert the analog signal into pulses. The most common method used is pulse-width modulation (PWM), which is why you may find Class D amplifiers sometimes referred to as PWM amplifiers. The PWM modulators may have problems with distortion in some implementations and can generate EMI (electromagnetic interference). The author also explains that with PWM, pulse widths become very small near full modulation, and because of the limited drive capability of the output-stage gate-driver, which cannot switch fast enough to produce the very short pulses, it is almost impossible to get full modulation. This means you cannot achieve full theoretical power. Alternatives to PWM include pulse-density modulation or PDM, which has an advantage when it comes to EMI, but has limited power efficiency. Another alternative, uses a self oscillating technique instead of the fixed frequency modulator used with PWM. This is the method used with the Hypex amplifers that we included in our prototype system. The self oscillating amplifier avoids some of the problems associated with PWM.

The sixth article, Class D Audio Amplifiers: What, Why, and How - Part 6, mentions that the high-frequency components of a Class D amplifier can generate a lot of EMI, which can interfere with the operation of other nearby equipment. The author then discusses several techniques used to minimize EMI.

The seventh and final article in the series, Class D Audio Amplifiers: What, Why, and How - Part 7, talks about the cost savings associated with audio systems that use Class D amplifiers. These costs savings are due to the higher efficiency of the Class D amplifers. Since they don't generate nearly as much heat, the systems don't need the large expensive heat sinks and chassis. However, the advanced circuitry for feedback loops and filtering adds to the expense. So in reality, using Class D amplifiers doesn't necessarily mean they will be less expensive than a system that uses Class A/B amplifiers.

Finally, a New SongSpot

I finally had a chance to change the SongSpot. The latest track is by Ryan Smith and features someone (?) from Rufus Wainwright's band along with The Silent League, and Loaded Dreams. The reason this may sound a little confusing is because the bio on CD Baby says this is a solo project and then it references the other contributors, but doesn't include any of their names.

Maybe the guy is from Wisconsin since it's called "Home Wisconsin". I always like to support home grown talent and you gotta love the toy piano. If you are interested in more info, he/they are going by the name A Million Billion. The album/ep is called 'the filthy schoolgirls'.

CES 2007 Review - Day Four 1/11/07

For the final day of CES, I decided to go back to the Las Vegas Convention Center and Hilton Hotel. There were a few important companies I wanted to visit and the CES guide showed they were exhibiting in booths at the Hilton. As it turned out, they didn't have exhibitor booths, but instead were actually in hotel suites. I figured that anyone listed in the CES book as an exhibitor meant they were willing to me with anyone with an exhibitor's badge. Unfortunately, that wasn't necessarily the case. Most of these companies were conducting meetings that were set up in advance. I probably should have used the online CES planner to make official appointments. Oh well, at least I now know what to do before attending next year's CES.

One of these companies was Intel Capital. It would be wonderful if Amplio Audio were able to get funding from this venture capitalist. After looking at the information on their Website, it looks like they would be an excellent match for a company like ours. Obviously, this is probably the kind of company that requires an appointment, but I thought what-the-heck, I'll just stop by and to introduce myself and maybe get some basic information about submitting a proposal when we are in a position to formally apply for venture funding. Most venture groups won't provide the first round of financing for a startup, but may invest once you're further along. Unfortunately when I stopped by, I was told the gentleman who was "in charge" had stepped out for a short while. His assistant told me they were only meeting with people with appointments and they didn't have any literature to hand out. Then another fairly nervous looking gentleman who had an appointment arrived and I was quickly asked to leave. So I politely said good bye and walked out the door. No harm done, they don't know who I was and it's not like I was rude or anything. BTW, I really don't like rejection (not that I was rejected).

The next company on my list was Asahi Kasei Microsystems (AKM Semiconductor). They manufacture DACs, ADCs, opamps, etc. - basically a lot of high quality audio chips. I was pleased to see Richard Kulavik, their US Manager of Marketing and Applications, there amongst the company representatives from Japan. I've had several phone and email conversations with Richard and he has been one of the most helpful representatives in the industry. It was nice to finally meet face to face. We spoke for a short while about how our product development was progressing and I asked him about a novel approach he suggested for a volume control solution. I couldn't (and really didn't need to) stay too long because their next appointment was going to arrive in a few minutes.

Another company who I've had some communication with for some time and had a suite in the Hilton was the ICEpower subsidiary of Bang & Olufsen. Even though they were also meeting people by appointment, they were happy to invite me into their suite and meet with me. The ICEpower amplifier modules are used in quite a few highly regarded products for both proaudio and consumer electronics. The Jeff Roland Design Group, who had a booth at the Venetian, is an example of a company that uses ICEpower technology in their products. ICEpower offers raw amplifier modules at a variety of power ratings and they also offer a more integrated solution that combines their amp module with a switching power supply. Their Technical Marketing Coordinator, Uffe Nisbeth, was very friendly and gave me a complete presentation of their product offerings. I had been under the impression that you had to commit to fairly large quantities before you could work with ICEpower and was happy to learn that this is not the case. We will be placing an order for several product samples in the next few weeks.

My visit to the Hilton wasn't a complete waste of time after all. Since the Las Vegas Convention Center was next door, I decided to spend the rest of the afternoon just casually browsing the exhibits. There wasn't much time left because on this last day of the show, the booths shut down an hour earlier than previous days. I think many of the exhibitors were anxious to get home, so some of them were packing up well in advance of the official closing time.

I had a chance to spend some time in the Dolby booth. They were showing off TrueHD, their multichannel, lossless audio technology for the new high-def discs Blu-ray and HD-DVD. I had a conversation with a Dolby executive about how high resolution audio formats like DVD-Audio and SACD have failed to become popular with a large number of consumers and if he thought that might change with TrueHD and the new disc formats. He didn't seem to be too optimistic, maybe that was because it had been a long week for him and he was tired. Anyhow, he said that it really depended on the music industry - the recording companies and labels, and they don't seem to have a clue. DTS also had a nice exhibit nearby and was promoting their lossless codec, DTS-HD, which will also play on Blu-ray and HD-DVD discs. The current confusion between Blu-ray and HD-DVD isn't really helping much either. I don't know if we'll start to see a lot of music (other than movie soundtracks) on either of these disc formats. I won't buy a stand-alone player, but plan to purchase a Blu-ray or HD-DVD drive for our HTPC in the future. Both of these codecs will work on either disc format. What we need is an affordable drive that can play and burn both Blu-ray and HD-DVD discs (and of course every flavor of DVD and CD) and it won't really matter whether they choose to encode to TrueHD or DTS-HD because either will work. Maybe then we will finally get a lot of high resolution music. With all the confusion slowing things down, maybe music downloads from companies like MusicGiants will become popular because they offer a solution that doesn't depend on any expensive hardware that could easily become obsolete. Rumor has it they will be offering multichannel 24-bit 96/192Khz audio tracks in the future. I'm disappointed that I missed their booth over at the Sands. I didn't think of them when I was putting together my itinerary before the show so I didn't even know they were at CES until it was too late.

So, that was my experience at CES 2007. After the exhibits closed, I had to wait around until later in the evening to catch a midnight flight back home. I was hoping to get some sleep on the plane, but couldn't get comfortable. I was probably a little wired from the past few day's activities. I had a nearly 5 hour lay over in Milwaukee until my final flight back home to Madison. All-in-all the red-eye out of Vegas turned out to be a very long trip. I don't recommend it.

I hope you enjoyed my CES 2007 reports. I plan to attend again next year and hopefully I'll be able to post these reports while I'm still at the show - instead of a week later.

CES 2007 Review - Day Three 1/10/07

On the third day of CES, I planned to focus almost exclusively on audio products. All of the exhibits for CES were basically at 2 main locations - the Las Vegas Convention Center/Hilton and the Sands Expo and Convention Center/Venetian (plus T.H.E. Show at the St. Tropez Hotel). The high end audio was on display in the Venetian Towers, so I decided to spend the full day at the Sands Expo/Venetian location.

I started out in the morning at the Sands Expo. I wanted to check out the MIT Media Lab, because they always have something interesting going on, but as it turned out, they really only had a meeting room. They weren't demonstrating anything at all and the room was empty when I visited. I also wanted to check out the Apple booth, and amazingly enough, couldn't find it. The booth layout and numbering was pretty screwy making it pretty difficult to find what you were looking for. Anyhow, Apple is never a big presence at CES because of MacWorld only a week later, where they make all of their big announcements.

I decided to stop by the Silicon Dust booth just to say hello and congratulate them on a great product. They created the HDHomeRun, which is a dual HD tuner that you connect to your home network. I purchased one of these about a month ago and have been pretty impressed. Here's how it works - After hooking it up to my network router (via Ethernet cable), I connected one of the tuner's inputs to the coax cable from my cable TV service and the other to a coax that runs up to an antenna in my attic. Then I installed the driver software on several of the PCs connected to our home network. I also installed SageTV on these machines. Now I can watch cable (QAM) or over-the-air (OTA/8VSB) TV on all of these machines, without having to install a bunch of TV tuner cards in each machine. It works great. I really enjoy watching HD programming on my 24" 1920x1200 HTPC screen (someday I'll invest in something like a 47" LCD monitor, but with any startup, money is tight). I wish I could view more HD programming because I'm limited to the HD/SD channels offered locally OTA by the major networks or the same programming that is coming over cable unencrypted.

There were a couple of companies at the Sands Expo that were audio related software developers. The first company, Garritan Soundware, developed a program called the Garritan Personal Orchestra (GPO). It is music production software for making orchestral music and includes a complete orchestral sample library, player and VST host. Instead of using electronically synthesized sounds with a sequencer, the GPO uses sounds that were sampled from actual instruments. It sounds amazing. With most synthesizers the sounds just don't quite sound real, especially the articulation from note to note on wind or horn instruments. However, with GPO you can control these transitions with your keyboard's controllers to make the instruments sound really natural. It's a very cool program for musicians or wanna-be musicians like myself.

The other software company I visited was MusicIP. They have what I think could potentially be a very cool product. In the future, I'll probably want to write a post dedicated to this, so I won't go into too much detail at this time. MusicIP is a program that creates intelligent playlists from your music library. Most players (Windows Media Player, iTunes) have smart playlist functionality, but not as sophisticated as something like MusicIP. I am very curious to see how it compares to my current player of choice - J.River's Media Center. With JRMC11, it will analyze my audio tracks and calculate the average beats-per-minute (BPM) and sound level intensity. Its media library also stores basic metadata info like Artist, Album, Genre, etc. and the date a track was added to the library, the last time it was played and the number of times the track was played. So, I can have it automatically generate a playlist of mellow jazz that I haven't listened to for a month and will play for 2 hours by specifying BPM is less than 100, intensity is less than 2, genre is Jazz and/or Vocal, the last time any of these tracks was played was over 1 month, the sort is Random and the time limit is 2 hours. It would be great if MusicIP exceeded JRMC's music library capabilities. I'm looking forward to testing it out.

I then moved over to the Venetian Towers where most of the high-end audio was located. Just like at T.H.E. Show, the hotel suites were converted to listening rooms. Even though the Venetian has very nice rooms, they weren't necessarily the best match for some of these systems both in terms of size and acoustics. There were a lot of exhibits, so I didn't have the chance to spend a lot of time in some of the room, but I did try to spend a little time in everyone. The manufacturers I'm writing about in this post have products that relate in some way to what we are trying to do at Amplio Audio. I've also written about a few that I think use interesting technology and looked a little unusual.

I visited the Bel Canto room to listen to their latest DACs because they use one of the leading contendors for our choice of DAC - the TI/Burr Brown PCM1792. The e.One Dac3 is a great sounding, well designed product. It's not cheap, but it isn't priced as ridiculously high as many DACs at this show, and I doubt there was much, if any, difference in sound quality.

I spent some time in the Channel Islands Audio room and spoke with Dusty Vawter, who I assume is the owner. They have great sounding products and also use components very similar to those we plan to use. Their DAC uses the PCM1794 and their highly regarded mono amps (see photo to the left) use Hypex Class-D amp modules that were custom designed for CIAUDIO with separate power supplies for the input and output sections.

I visited the booth of British semiconductor manufacturer Zetex Semiconductors, who were showing their Class-Z direct digital feedback amplifier. They were also at last year's show, but the product was still in development. Unlike the Hypex technology (and most Class-D amps), these are fully digital. They take PCM data from an I2S input and convert it to PWM, which is amplified. Their specs are pretty impressive - dynamic range of 120 dB, and distortion and noise less than 0.004% from 1W to 250W into 8Ω. Another manufacture, Theta Digital, uses them in their multichannel digital amps and is very happy with the performance. This is something we plan to look at very closely in the near future. They sounded pretty good, but I'm not convinced that they are an improvement over the state-of-the-art Class-D amps we've been working with lately. If they do outperform the Class-D amps, it would also mean we wouldn't have to include the DACs and analog circuitry. This would simplify our design and possible lower our costs (I haven't seen any pricing on the Zetex parts). However, it would also mean that we'd have to take more time to develop our product.

I'm very interested in digital room correction and digital crossover technology, so I spent some time with several vendors to learn a little more about their approach. It was interesting to learn that DEQX, an Australian company that focuses on room and loudspeaker correction preamp/processors, was demonstrating an NHT Xd system (which was one of the first to incorporate the DEQX processor), except they substituted the standard amps with Hypex UcD400. They said they favored the UcD400's performance over the amps that were normally included with the Xd system. The system sounded great, but I must confess, I didn't get to A/B the setup with room/speaker correction turned on and off. DEQX believes the weak link in the audio chain is the loudspeaker and its interaction with the room. They also believe a good preamp or amplifier is very transparent, meaning they don't introduce errors and distortion of their own. The loudspeakers are the biggest challenge because they are a mechanical device and no single driver can produce the entire audio spectrum ideally. Because of this, they say, "the speakers introduce far more errors and distortion than the totality of the audio chain that precedes them." So with the DEQX processor, they try to bring the loudspeaker distortion and errors down to levels approaching the electronics. Their system is designed to reduce errors and distortion caused by the loudspeaker itself, as well as room acoustic problems.

I was also fortunate to sit in on an excellent presentation in the Tact Audio room. They offer a full line of digital amps and processors. They are also very focused on specialized room correction technology. During their presentation, the room correction was toggled on and off so you could experience the difference. Even sitting off to the side I could hear the bass tighten up and the highs became clearer with room correction on. The improvement in the lower frequencies was very noticeable.

There was also a speaker manufacturer with a unique design, from Kubotek called the HANIWA Cybernetic Audio System. This system integrates large horn speakers with a DSP unit that provides digital crossovers with frequency, phase shift, impulse response and step response analysis. I thought they sounded excellent and I'm not a big fan of gigantic horn speakers. As you can see by this picture on the left, they may not pass the wife-acceptance-factor (WAF) test. They gave me an excellent brochure that includes a little blurb on how the speaker cabinets are built.

The first photo to the right shows how MDF or laminated plywood, which is cut into 1 - 2" sheets is stacked and glued together.

The second photo to the left shows how the laminated block is pressed together for 3 days to firmly fix the lamination.

The third picture on the right shows how their CNC machine is used to precisely mill out the cabinet.

Another interesting speaker design was the very tall prototype from the German manufacturer Meletzky Berlin Loudspeaker (MBL). Their omni directional speakers are made up of a bunch of stacked spherical (actually they are more like oblong spheres) drivers, which they call "Radialstrahlers". The Radialstrahlers are made up of carbon-fiber petals, which they call "lamellas". Anyhow, it is pretty unique stuff. I think they mentioned the retail price will be something like $150,000 for a pair. I'm not sure if they are worth it. That amount of cash can buy a lot of plane tickets to the best live performances on the planet. I have to admit, they sounded pretty impressive. I kind of expected them to have weird imaging because of the 360° omni directional output, but surprising they don't. The soundstage did seem pretty open and "live" and at the same time 3 dimensional and accurate. The instruments and vocals all sounded like they were in the right position. They also sound pretty good with a variety of material - jazz, vocal, rock, blues, classical, etc. Most of the other exhibitors were playing Norah Jones or Diana Krall, and I think female vocals sound pretty good on just about any system. So it was nice to listen to something else for a change. As you can see from these pictures, they may not pass the WAF test, unless you have a house with Victorian furniture or some other dramatic style.

For those of you who like the looks of big iron (or aluminum), check out these monster amps from Ypsilon Electronics. Most of the home theater PC enthusiasts I've talked with have gone out of their way to build the PCs so they look more like consumer audio equipment. This is the first time I've seen an audio manufacturer build an audio device that looks like a big tower standing PC. Choice is good. Do you think these would pass the WAF test?

In conclusion, there were quite a few high-end (expensive) systems that didn't really impress me and there were some reasonable priced stuff that I thought sounded really good. So the saying "you get what you pay for" doesn't always apply. There were some products that used expensive components and wild design that just didn't sound as good as some of the less expensive products with more basic designs. I also can appreciate the fact that some of these very expensive components also sounded amazing. My next post will cover my final day.

CES 2007 Review - Day Two 1/9/07

Tuesday was a pretty busy day for me at CES. I started it off with a breakfast meeting with Jim Kinne of Digimeister Design. I was held up waiting in line for the monorail, so I was about 15 to 20 minutes late, but since Jim was also held up in traffic, he had only been waiting for me for a few minutes. I was planning to sit in on Michael Dell's 9:00 AM keynote address that morning, but meeting with Jim was much more useful. Besides, I can always stream Michael's keynote off the Dell's webserver.

After breakfast, I headed over to the Las Vegas Convention Center where all the big companies were strutting their stuff. I stopped by the Microsoft booth to ask a few questions about Vista Media Center. I'm having some problems with video playback and was hoping someone could help me out or at least point me to the best support resource. I also took a look at demos of the latest Office 2007 while I was there. The new UI for Office is pretty cool. I'm looking forward to installing it on my office machine once I finally upgrade it to Vista. Of course Microsoft had a huge booth and the big emphasis was on the upcoming consumer roll out for Vista. They also had a big section within their mega-booth for showing off their Zune. One of the many Microsoft stages was promoting Crossfader, a Microsoft created online community for digital artists. During the Crossfader promotion, I briefly met Arif Gursel who is a Program Manager for Microsoft's Devices and Media Team. We didn't get much of a chance to talk, but he seemed pretty interested in what Amplio Audio is doing. I'll try to touch bases with him in the near future.

There was a guy from Hewlett Packard working at the Microsoft booth demonstrating Microsoft's Home Server software running on HP's MediaSmart Server (see picture to the left). This kind of reminds me of a more user friendly Unraid system. The user doesn't have to worry about setting up a raid array and doesn't have to purchase a set of matching hard disk drives. However, with the Unraid system, every drive execpt the parity drive is providing full storage capacity. For example, with Unraid, if I have 3 x 500 GB drives, I end up with ~ 1 TB of storage space. With the Microsoft Home Server solution, I would get 750 GB of storage space from 3 x 500 GB drives because it is basically mirroring your disks. The Microsoft Home Server sounds a lot easier to set up and manage, so the loss in storage capacity might be a reasonable trade-off. I guess to be fair, I should also mention one other advantage of the Unraid system is price. I would suspect the price of a DIY unraid system to be quite a bit lower than a Microsoft Home Server setup with the same capacity.

I also swung by the Sony booth to say hello to my former co-workers from Sonic Foundry (who's media software division was purchased by Sony a few years ago). Unfortunately, most of them weren't hanging around the booth at that time. I think they were out enjoying CES. I can't blame them - I don't envy anyone who has to work a booth at one of these big shows. Anyhow, I did get to say hi to Gary Rebholz who is now the Training Manager for Sony Media Software, who I haven't seen since I worked at Sonic Foundry. Sony's booth was also pretty large and while I was visiting, there was a live performance featuring Sara Bareilles (see photo to the right).

I also spent some time watching some of the other spectacular exhibits. Panasonic had a bunch of high def plasma screens set up as the backdrop for their stage. This photo to the left shows the performers appearing simultaneously on stage and on the plasma screens to show off the impressive high resolution or realism of their plasma screens. They were trying to imply that you couldn't tell the difference between the live performers and the ones appearing on their plasma screens, but obviously even with the great colors and high contrast, high resolution of these displays, there's a big difference between the actual 3 dimensions of the live performers and the flat 2D displays.

Quite a few companies were showing their latest and greatest LCD HD screens. The ones that were getting the most oohs and aahs were the large screens from LG and Sharp. The LG screen shown in this picture on the left, measures 102" diagonally. If you walked right up to this LG screen, you could see a vertical seam running right down the middle. You had to get very close and stand slightly off to the side to see this. From a typically viewing distance of >10', I don't think you could possibly see it. Sharp's 108" Aquos LCD screen (see photo to the right) was the largest LCD TV I saw at the show and as you can see from their display, they claim it is the largest in the world. This screen was amazing looking and I did not find any seams with close inspection. They also had a bunch of really nice smaller screens like 42", 46", 52" and 65" that looked great. And, it looks like the prices are coming down.

By this time my legs and feet were getting a little sore from standing and walking, but I did get a chance to stop by the booths of Lian Li, Silverstone, Cooler Master and Thermaltake to see the latest and greatest chassis designs for HTPCs and servers. Lian Li might even be a possible source for amplifier chassis because they said they are interested in any potential OEM/ODM project.

After a day full of stomping around the big exhibit hall, a little rest and relaxation was very appealing. The week before CES I received an invitation to a bloggers reception being held later Tuesday afternoon at the Atomic Testing Museum, so I navigated my way over there by shuttle and bus. I met several people, most of which I'd consider professional bloggers. By professional blogger, I mean someone who receives revenue by running advertisements on their blog or through some subscription program. A few of the pro bloggers I met were Doug Felteau, Chief Gizmateer of Gizmos for Geeks, Steve Brobeck, founder of the Blog Business Summit, who mentioned that he has a book that teaches you how to drive more traffic to your blog, Drew Crouch of Ask Dave Taylor!, and Al Carlton of coolest-gadgets.com. and . There were a few bloggers like myself, who don't try to generate revenue from their blog, but instead use it as a communication tool to talk about their company or products, like Loren Feldman of 1938 Media, and Nick and Dave Gray of Flight Display Systems. Their company sells and installs high end audio/video systems in private jets. Actually, it looks like Nick might be using his blog to meet chicks :).

The last event of the day for me was the 6th annual AVS Forum CES 2007 Party. I made it over to the Sahara Hotel's Golden Ballroom, where the party was held, just in time to get a little bite to eat before they hauled all the food away. I hung out for a little while to listen to the funk and soul, then headed back to my luxurious motel.

CES 2007 Keynotes

The only keynote I was able to sit in on was the Monday afternoon keynote by Disney's CEO, Robert Ager. Like I said in my earlier post, it was a nice 1 hour Disney promo. Disney sure has a lot of content and they just can't wait to get it to you... sort of.

I missed Bill Gate's keynote Sunday evening, since I didn't arrive until Monday morning. Even though I really enjoy demonstrations of home automation with audio and video gadgetry, I don't think the keynote was as interesting as this lunch meeting he had with several bloggers earlier that day at CES. At about 15 minutes into this conversation, Bill comments that they will push downloadable content as much as they can (HD-DVD is great, but eventually online will be more important), but there are digital rights issues slowing things down. He mentions that this is not as much of a problem with their Xbox consoles because of their closed architecture. Then Ryan Block, Managing Editor of Engadget commented that in the future, the living room (meaning the Xbox) will be a more important platform for Microsoft than the PC. Bill disagreed and said "no, Media Center is way richer." He goes on to say that Media Center (meaning HTPCs running Window's Media Center) is the superset device and represents a gigantic market because of the openness and variety of PCs. He also mentioned that PC gaming will be where you'll see the cutting edge high end gaming happening, partly because of all the advanced graphics technology being developed by ATI and NVIDIA.

CES 2007 Review - Day One 1/8/07

My flight left Madison at 6:00 AM, so it was an early start. I had to take a puddle jumper to Milwaukee and then I flew to Las Vegas, where my arrival was sometime around 8:50 AM with the time change. I took an airport shuttle to my motel and learned that check-in wasn't until 3:00 PM and was told they didn't have any rooms available at that time. This was a problem because I really needed to drop off my suitcase/bag before heading out and visiting the exhibits. I really didn't feel like carrying my heavy bag all day. Most hotels would let you store your bags with them in some safe place, but not the Wild Wild West. The lady at the reception desk didn't recommend storing my bag with them because, she said, "there's all sorts of people walking back there, and you never know what they might grab." This hotel is not exactly what I expected. It made the Howard Johnson's that I stayed in last year look pretty good. And, I really didn't want to stay in the HoJo's again. There were some pretty nasty bugs crawling around in the bathroom. By then it was nearly noon Madison time, so I decided to grab lunch at their Gambler's Grill. After lunch I gave it another shot at the reception desk and was able to get into a room. Thank goodness I could finally get rid of my bag.

A few days before leaving for the show, I put together an itinerary for my 4 day visit. This included all the different exhibits that I wanted to check out. First up was T.H.E. Show, where I wanted to meet with Adire Audio, April Music, Benchmark and Empirical Audio.

Adire Audio used to be a distributor for Hypex Class-D amplifier modules and their website used to include some useful power supply circuit diagrams. I don't think they deal with the amp modules anymore because they are focusing all of their efforts on their speaker drivers, which they sell to high-end speaker builders. At their booth, I met and spoke with the owner of a speaker manufacturer named Tympanik (unfortunately, I didn't write down his name). It was nice talking with him and sharing similar experiences with our audio related startup businesses. He's a little further along because they have a product ready to ship, but he's also been at it for about 3 years.

At April Music's booth I met with Simon Lee. I also met him at last year's CES and have been talking on and off with them about an engineering/manufacturing partnership. They are located in South Korea, so obviously they have much closer connections to Asian manufacturing centers. They've also produced some pretty nice products including their Stello DA220 DAC, which has received a few great reviews. Their latest product is called the Aura note (see photo at left), which they refer to as the "CD/AMP Completer" because and it combines a preamp, amp, CD transport, DACs and tuner. All you need is a good pair of matching speakers and you are good to go. It also includes a USB connection so it can be used to play audio from your PC. It's limited to 2 channel stereo and the built in decoder only supports MP3, WMA and OGG up to 192 Kbps. The built-in encoder will only let you record MP3s at 128 Kbps.

I didn't get a chance to speak with anyone from Benchmark. They were sharing a booth with a distributor named Studio Electric and no one actually from Benchmark was around. I did get a chance to speak with Steve Nugent of Empirical Audio. Steve's a really nice guy and was willing to share some of his knowledge of DAC design (they offer upgrades or modifications to Benchmark's DAC1) and the importance of reducing jitter. While visiting their booth, I also met the woman who organized both T.H.E. Show and the Rocky Mountain Audio Fest. They introduced her as the latter and it wasn't until a little later that I learned about her involvement with the former. So, I probably put my foot in my mouth when I commented that the exhibitors were not getting nearly enough traffic to justify their expense because the change of venue for the CES high end audio was moved away from their location. Last year, they were right next to each other, so many people who visited the CES high end audio exhibits (next door at the Alexis Park Resort) were walking over to the St. Tropez Hotel, where T.H.E. Show was located. Anyhow, I've heard great things about the Rocky Mountain Audio Fest and will try to attend it next October in Denver.

I didn't cover as much ground as I planned the first day. Transportation from venue to venue is not as quick as I'd like. Traffic in Vegas during CES, to put it mildly, sucks. I spent a lot of time on the CES shuttle bus waiting in traffic. I finally made my way to the Palazzo Ballroom at the Venetian Hotel to listen to the keynote by Disney's Robert Ager. It was a nice 1 hour Disney promo. Of course he had some nice visuals and we got to see the stars of their TV show 'Lost', which I've never watched, but quite a few people in the audience thought that was pretty exciting. Stay tuned for day 2.

"T.H.E. Show"

Last year (my first CES experience), most of the high-end audio stuff was on display at the Alexis Park Resort Hotel. Nearby, there was another event called "T.H.E. Show" (short for The Home Entertainment Show) and was kind of like a sub-convention within CES. This year the High-performance Audio & Home Theater exhibits have been moved to The Venetian.

In honor of "T.H.E. Show" this weeks SongSpot selection is a song called Last Show With Joe by the Free Radicals from their CD Aerial Bombardment. For some reason this tune seemed to capture the right mood for me.

Out of touch, Out of Town

I've been a little distracted lately.

Been busy with the holidays and spending a lot of time with my family. I was an iPod virgin until getting my 12 year daughter a 4 Gb blue iPod Nano for Christmas. In a future posting, I'll have to share (or rant about) my experience with Apple's legendary user friendliness. Some features of the iPod/iTunes technology really drives me nuts. Oh well... my daughter really loves it.

We also spent a little time up in northern Wisconsin this past week. My wife and I are avid cross-country skiers, and with the lack of snow here in Madison, we headed north in search of better conditions. There's snow up north, but the conditions aren't great. With very mild temperatures, the snow was deteriorating by the hour.

In a few days I'll be leaving for Vegas to attend CES 2007. The purpose of my trip is to meet with representatives from some of the companies who provide the components for our products. However, I hope to have time to check out the latest and greatest in audio and video gadgetry.