Saturday, July 15, 2006

HTPC Diary Part 2: Tunerama

What Makes an HTPC an HTPC?

Before I go into the results of my research into TV tuners, it might be helpful to break down exactly those qualities that differentiate an HTPC from any regular old PC. Of course, both share many features, such as hard drives, a motherboard, an operating system, etc. But there are a few things an HTPC must have above these:

TV Tuner - Until the media companies start beaming digital, pre-compressed feeds of television programs straight through the Internet, an HTPC needs something that will grab a TV signal off the air or cable box and convert it to a workable format. Some media companies are doing this already through iTunes or, in the case of some ABC shows, on their own website. But iTunes downloads aren't free, ABC's streaming feeds can't be archived, and these only represent a tiny fraction of all the shows available.

TV and Audio Out - The HTPC must also have the hardware allowing it to convert the digital signal back into analog for display on a conventional TV set. That is, unless one has an HDTV with DVI inputs, or plans to use a monitor instead of a TV. I'm still kickin' it low-tech with my 27 inch cathode ray. So I'll need something with S-Video or Component outputs (I may not have the fanciest TV, but even I would never use composite video). And even the lowliest of motherboards now has, at the very least, stereo audio output.

Media Center Software - To schedule recordings, play back video and sound, and do a host of other media central things. Lots of options here, which I'll get into later.

Remote Control - Unless you want to whip out the keyboard every time you need to change the channel.

Smaller case and quieter components - Actually optional, but do you really want a noisy monstrosity ruining the mise-en-scene of your harmonious living room?

That's about it. Of course, to get everything to work together reliably and optimally, one has to put a lot of consideration into the selection of all components. But these are the minimums.

One more consideration. Let's say you have a fairly modern PC in another room already. Do you have to build a whole new machine? You could just add a TV tuner and media center software and then buy a media bridge, such as the Sage TV Media Extender to stream content to your TV wirelessly. For this you would also need a cable hook-up in the same room as your PC, which is one reason why I won't be going this route.

Tuner Salad

Microsoft jumped into the HTPC fray in late 2004 with their Media Center Edition operating system, a version of Windows XP with integrated Tivo-like functionality. I probably won't be using this OS for my box, for reasons to be explained later, but the software has, and will continue to have, a strong impact on TV tuner manufacturers and HTPC builders. Microsoft has, in a sense, set a de-facto hardware standard for media PCs, one that should not be ignored lightly. Expect better third-party application compatibility for Windows MCE-supported hardware as the operating system gains widespread use, and as Microsoft incorporates many of its features into Windows Vista.

And not just because Microsoft is the 500-lb gorilla will I be following their hardware requirements. Many of them, including their specifications for TV tuners, just make sense. Under Windows MCE, a TV tuner must have hardware MPEG 2 encoding. Some tuners, like the ATI All-in-Wonder 9800 Pro that powers my current PC, merely have a TV receiver and offload the processor-intensive task of encoding that video to the CPU. By selecting a TV tuner with hardware encoding, you reduce the load on the rest of the system, which means you can use more modest (read less expensive) parts.

Three Typical Selections

On nearly every hardware news or HTPC building resource I visited, three options seemed to dominate discussions of TV tuners: the Hauppauge Win-TV PVR line (150, 250, and 500), the Nvidia DualTV MCE, and cards based on the ATI Theater 550 Pro chipset (such as ATI's own TV Wonder Elite).

The Nvidia DualTV is a well-reviewed two-tuner card, which means it can record two shows at once. This is a great feature. However, this card is also priced about twice as high as other single-tuner cards ($170 at the Nvidia store, the only place I can find it). To keep the price of my system low, I'm going for the single. I can always add more tuners later, as most DVR software supports the use of multiple tuners.

The Hauppauge 150 seems a popular choice among HTPC builders, but reviews warn its picture quality is not up to snuff in comparison with the ATI and Nvidia cards, which are ITF certified and have all sorts of digital comb filters and the like, none of which is particularly meaningful to me, but they do seem to result in better video according to side-by-side comparisons.

So that leaves the Hauppauge 250 and the ATI Theater 550 Pro. In reviews, the two cards are said to perform comparably, with the ATI chipset narrowly edging out the other on video quality. But the ATI tuner can be found in cards costing almost half as much as the Hauppauge, perhaps because ATI licenses its technology to multiple card manufacturers. Packages vary widely, with some brands providing a remote control and more premium bundled software.

If I were to buy a TV tuner card today, therefore, it would be one based on the ATI chipset. Specifically, the VisionTek VTK-THXP550P comes bundled with Snapstream's BeyondTV software for just $60 after rebate, or about $110 with an included MCE remote.

To ATI or Not To ATI

One trend among system builders I noticed just did not make any sense to me at first. Why are the Hauppauge cards so popular if their products are so inferior? It took me a while to figure it out: Linux compatibility. Apparently, ATI is not so proactive in their Linux support, and have yet to release a driver for the 550 chipset. Choosing ATI, then, means choosing not to install Linux as your operating system, and that means the high cost of purchasing a copy of Windows. This would break my budget. I don't have an extra $100 to spend on an OS.

Fortunately for me, due to my student status, I happen to have a license for Windows XP Pro sitting around (don't be too jealous, this minor perk comes after paying $30 grand in tuition). So I will indeed be using an ATI card. I'll be missing out on the most popular open-source media center application, MythTV, but should still have plenty of options (more on that later).

But if you don't have a free Windows license and still want to build the cheapest possible HTPC, the Hauppauge Win-TV PVR 250 seems the most economical choice. Or even consider the Nvidia--though an expensive card, the money you save by using Linux will offset the extra cost.

But Wait!

All of that being said, I probably won't purchase any of these cards. ATI is coming out with an update to their 550 Pro chipset: the 650 Pro. Though they haven't released the hardware to the public yet, many reviewers have received test copies. The result? The new chipset provides even better image quality. What's more, the tuner can receive regular analog plus ATSC broadcasts. ATSC is the over-the-air HDTV standard. With an antenna, and depending on proximity to the broadcast tower, one may be able to pull down free HDTV from the major networks. I know, I don't have a digital TV. But it's still cool. And, even downmixed to standard resolution, HDTV broadcasts should still be clearer than Boston Comcast's dodgy analog cable.

Tuner cards based on the 650 Pro should start coming out this month. Remember, I said my goal was to get this thing built by the end of summer. Stay tuned to see if a new card makes it into my machine.

Wednesday, July 12, 2006

HTPC Diary Part 1: Introduction and Justification

I've been spending inordinate amounts of time over the last several weeks researching components to build my own home theater PC (or HTPC, or Media Center PC, etc), so I thought I'd serialize my thoughts, processes, difficulties, and conclusions for anyone who might be interested, or who might be able to give me advice along the way. This will be the first in a series of posts as I select components to buy, put them together, and test the machine. Today I will address the most obvious question about this task: why?

DIY HTPC: Not Just a Really Expensive Tivo

My VCR had been on the fritz for several months before my wife and I moved from Oakland to Boston to attend grad school. It played tapes reliably, but recording was a crap shoot. About half the time it would shut itself off after recording was engaged. So when hard decisions had to be made about which items would earn valuable space in our packing crate, it didn't make the cut. And I couldn't bring myself to buy a new one for our new home. Buy a VCR? Why not churn our own butter? Hello, digital technology.

But some deep-seeded geekiness (or genetic cheapness) also prevented me from buying a Tivo. It's just a function-crippled Linux box with a TV tuner, I could make one of those! More pointedly, my student budget would not bear the monthly service charge.

Subsequently, during a busy year of graduate study, we missed all of our shows. I resolved to find a solution by the end of the summer. As God as my witness, I will never miss The O.C. again!

Tivos are now essentially free. Buy one at retail and you'll get a rebate covering most of the cost under the condition that you'll subscribe to the monthly Tivo service for one year. Depending on how you look at it, they're either subsidizing the cost of the hardware or the first year of the service. They've also introduced two- tuner decks which can record two shows at once, and are experimenting with direct delivery of content to Tivo boxes over the Internet. Still, I refuse to buy a Tivo.

Here's why. Unlike when VCRs first came out and the hardware manufacturers fought the media industry tooth and nail in the courts to protect the consumer's right to record and archive broadcast TV, Tivo has cozied up to the TV industry, presumably to avoid such costly litigation. Instead of fighting, they've simply sold their customers out. First, they buried the 30 second skip function to make it more difficult to zap commercials. More recently, they've allowed the networks to flag shows for restricted access. Some shows will self-destruct if you don't watch them soon enough, others can't be recorded at all. This is unconscionable.

Frankly, I also refuse to pay for the Tivo service on principle. What is it that they're charging you for? Let's look at the elements that go into it. First, there's the program guide, the list of shows and showtimes and other metadata. This information is important, sure. But another way to look at it: these are advertisements. TV networks aren't carefully guarding the secret of when their shows are airing. They want you to know! Second, there's the data about your viewing habits that Tivo uses to make recommendations for other shows. The key word in that last sentence: YOUR. This is data you provide, and valuable demographic data at that. Tivo should be paying you to access it.

Those are the only truly dynamic aspects of the service. Tivo synthesizes these streams together with some statistical intelligence and a graphical front-end to provide their characteristic new media experience. What's a better term for this "service"? Software. But software you pay $13 a month for.

Other Options

Given my stand against Tivo, I did consider some other options.

Comcast offers cable subscribers the ability to lease a DVR for about the same amount as the Tivo service charge. But since Tivos now subsidize the cost of hardware, why lease when you can buy? Also, you have to have digital cable to lease the box, and I don't.

You can find DVD Recorders/Hard Drive hybrids which allow broadcast recording without paying a service fee, many of which also pull schedule information off the air for very limited Tivo-like functionality. These seem a good step forward, but they are also quite pricey, starting at $300. I feel confident that, for about a hundred bucks more, I can build something far more versatile.

The Dream Machine

My goal is to create a low profile, lowish noise PC that can sit with my other home theater equipment but do a whole lot more: the fabled convergence box. It should be able to do all the stuff Tivo does (program guide, "season pass" recording, pause live TV, etc), in addition to these things:

play all of my digital media
network with my desktop PC to share files
browse the web
run bittorrents when necessary
serve as an emergency backup word processor when my wife and I both have papers due

and maybe even:
run limited games (ideally arcade and early console emulators)
pull down over-air HDTV signals

That's the project. I've seen a lot of HTPC tutorials, but most are pitched at a much higher budget than mine; people building high-end vanity equipment or otherwise high-powered PCs with DVR functionality. My aim is to get a minimal configuration working for around $400, but which will support plenty of future upgrades.

The components are interdependent, but I have to start somewhere, so next I'll be looking at the heart of any HTPC: the TV tuner card.