Back in August, I wrote a post about some guy, Troy aka pcCinema, who on the AVS Forum proposed to help people build HTPCs. He was going to test different components to make sure they could play all the disc formats (HD included), play and record TV, play music, etc., etc. This would be real helpful for people that have struggled with matching the right hardware with drivers and codecs to play their media glitch free. He would post a list of components that passed his tests so people could just purchase the hardware from online vendors and feel confident that it would just work. He was also going to create installation routines to help people get the correct software, drivers and codecs to tie everything together seamlessly. A lot of people responded to his offer and a few of them offered to help out. A couple of guys, greeniguana and binary64, offered to do more sophisticated scripting to take it to the next level. This included tracking the current versions and automatically going to websites to download the most stable and compatible software. Like I said, it was pretty promising and it generated a lot of interest judging by how many people were responding and reading the thread. There were quite a few people who even donated to a fund so Troy could buy some of the hardware needed to start testing.
Troy/pcCinema decided to quit his own project. I don't know exactly what happened. You could try reading the thread to see if you can decipher it, but it looks like pcCinema just couldn't continue the project. Maybe his injuries (I think injured back) were more than he could handle. Or some people accused him of being a scammer and using his plan to get some donations so he could buy some hardware. I think the former is probably the real reason. There were a few people who were suspicious from the start and they questioned his motives. He didn't handle the criticism very well and probably helped fuel the fires of doubt. After quiting, it would have made sense for Troy/pcCinema to either return the donations or pass the hardware on to people who were willing to help out with the project. He did neither and instead probably pissed off everyone who trusted him, especially greeniquana and binary64.
Meanwhile, it looked like greeniguana and binary64 were going to continue on without him. If they could get their software to work with any hardware, they could really help a lot of people. If you are interested in what they are doing, just respond to the original thread. They also meet every so often on the IRC chat line called "HTPC Project." I think the irc address is 71.244.119.244:6667. The hostname is irc.htpcprojectchat.com. If you search the thread you can probably find the information you need to contact them.
There was also a guy named "renethx" who provided a lot of really good information about hardware. Troy/pcCinema basically delegated all hardware choices to him because of his impressive knowledge. As it turns out, renethx created his own thread with detailed hardware recommendations. I even used it to help select a few components to upgrade our demo HTPC.
So maybe there is still hope. Between renethx's hardware recommendations and the other guy's software scripts, people can find some very good information and potential setup tools to help them build and setup advanced and stable HTPCs.
Monday, December 10, 2007
Friday, November 02, 2007
iTrax Almost Ready
In a previous blog post, What is HD Audio?, I mentioned that AIX Records was going to launch a new website where you could purchase and download 24bit/96KHz high resolution audio tracks and albums. It looks like they are almost ready to go.
For those of you who have never heard a HD audio track, here's your chance. They let you download a sample track after you register on their website. Their HD audio was actually recorded using HD recording equipment. This isn't previously mastered stuff resampled into HD, like a lot of music currently on SACD or DVD-Audio. It was recorded, processed and mastered in high resolution.
To check this out, go to their website at iTrax.com.
When you register, they will reward you with a sample track that you can download. If you pick 'Login' at the bottom of the webpage, it will take you to another page that will let you register. I think the website is still in beta, so some things may not be working. Unfortunately, they don't let you download both a 16bit/44.1KHz version and a 24bit/96KHz version for comparison purposes, but at least you can try out the 24bit/96KHz track.
BTW, it sounds really good on our demo system. I'm looking forward to purchasing more of their music. I'm not familiar with most of their artists, so I'm open to any recommendations.
For those of you who have never heard a HD audio track, here's your chance. They let you download a sample track after you register on their website. Their HD audio was actually recorded using HD recording equipment. This isn't previously mastered stuff resampled into HD, like a lot of music currently on SACD or DVD-Audio. It was recorded, processed and mastered in high resolution.
To check this out, go to their website at iTrax.com.
When you register, they will reward you with a sample track that you can download. If you pick 'Login' at the bottom of the webpage, it will take you to another page that will let you register. I think the website is still in beta, so some things may not be working. Unfortunately, they don't let you download both a 16bit/44.1KHz version and a 24bit/96KHz version for comparison purposes, but at least you can try out the 24bit/96KHz track.
BTW, it sounds really good on our demo system. I'm looking forward to purchasing more of their music. I'm not familiar with most of their artists, so I'm open to any recommendations.
Thursday, November 01, 2007
Go Green with Class D Amps
Here's an article from Electronic Design that talks about the advantages of running a Class D amp when compared to other amplifier designs with regard to power efficiency.
They explain that an amplifier works by applying a voltage of alternating polarity to a loudspeaker, driving it back and forth to move the air that produces the sound. The amp basically has 2 power rails for the + and - polarity voltages.
With a Class A amp, both switches are on simultaneously to create the required voltage, so they're only about 15% efficient. This means that only 15% of the power is used to drive the speakers. The other 85% is lost as heat. That's why the higher power (over 100W) Class A amps are usually pretty large and include massive heat sinks. With Class B amps, only one switch is on at a time, resulting in efficiencies of around 75%. Unfortunately the trade off is poorer sound quality. Class AB is a combination or compromise between A and B with both switches on simultaneously, but the non-load carrying rail was only minimally on. This improved the sound, but only resulted in efficiencies of about 30% due to switching losses. The Class D amp does this by switching these voltages on and off. With the Class D amps, the switching losses are very low resulting in an overall efficiency of more than 90% with very good sound quality.
Read the article if you are interested in more of the details.
They explain that an amplifier works by applying a voltage of alternating polarity to a loudspeaker, driving it back and forth to move the air that produces the sound. The amp basically has 2 power rails for the + and - polarity voltages.
With a Class A amp, both switches are on simultaneously to create the required voltage, so they're only about 15% efficient. This means that only 15% of the power is used to drive the speakers. The other 85% is lost as heat. That's why the higher power (over 100W) Class A amps are usually pretty large and include massive heat sinks. With Class B amps, only one switch is on at a time, resulting in efficiencies of around 75%. Unfortunately the trade off is poorer sound quality. Class AB is a combination or compromise between A and B with both switches on simultaneously, but the non-load carrying rail was only minimally on. This improved the sound, but only resulted in efficiencies of about 30% due to switching losses. The Class D amp does this by switching these voltages on and off. With the Class D amps, the switching losses are very low resulting in an overall efficiency of more than 90% with very good sound quality.
Read the article if you are interested in more of the details.
Friday, October 19, 2007
Report Shows More Home Theater Owners Want PC Integration
A recent study by The NPD Group found that 17 percent of consumers are interested in accessing PC content from their home entertainment system (25 percent for consumers with a home network).
“[Faster] Internet access, new content sources, and the evolution of the PC as a multimedia repository promise to change the features and functionality of devices in the home entertainment center,” says Ross Rubin, director of industry analysis for The NPD Group.
Now I need to update my business plan with some of this informtion.
“[Faster] Internet access, new content sources, and the evolution of the PC as a multimedia repository promise to change the features and functionality of devices in the home entertainment center,” says Ross Rubin, director of industry analysis for The NPD Group.
Now I need to update my business plan with some of this informtion.
Wednesday, October 17, 2007
Michael Fremer Takes the Million Dollar Challenge
Last Thursday, I wrote a post about James Randi's offer to pay anyone $1 million if they can prove that a $7,250 pair of Pear Anjou speaker cables sound different than their Monster Cable equivalent. It looks like Michael Fremer, a Stereophile Magazine writer, has decided to take up the challenge. To learn more, read this post in Gizmodo. This should be fun.
Tuesday, October 16, 2007
Sony BD-ROM Drive
I read another article today that mentions Sony plans to sell a Blu-ray disc reader for the PC aftermarket in early 2008. They plan to sell the drive, which will not include any writing capability for any disc format, for under $200.
Since many people (NCIX) have reported seeing $299 prices for the LG GGC-H20L hybrid Blu-ray and HD DVD reader, which is also capable of writing DVD and CD disc formats, I don't think people will get too excited by the Sony price. For $99 more, you get a hybrid drive that reads both of the HD disc formats and can replace your DVD/CD burner.
Since many people (NCIX) have reported seeing $299 prices for the LG GGC-H20L hybrid Blu-ray and HD DVD reader, which is also capable of writing DVD and CD disc formats, I don't think people will get too excited by the Sony price. For $99 more, you get a hybrid drive that reads both of the HD disc formats and can replace your DVD/CD burner.
Download & Install The New Vista Service Pack
This post is just a link to the instructions. Not sure if I'm willing to go through this hassle to get the service pack myself, but you are welcome to give it a try. I think I'll wait until the official release.
Sunday, October 14, 2007
How Much Storage Space Will I Need For HD Audio
I've been following several threads (including this AVS Forum thread) that talk about how the audio tracks of an HD DVD or Blu-ray movie when played on your HTPC using PowerDVD Ultra are downrez'd from 24bit/48kHz to 16bit/48kHz because of copy protection issues. I think they say you cannot pass the full resolution digital audio of protected (flagged) sources unless you have a protected path. The protected path is all part of the solution that makes it impossible to copy high resolution audio and video using DRM schemes like AACS for audio and HDCP for video. It seems PowerDVD is trying to comply by just converting every audio track down to 16bit/48kHz even if the tracks are not flagged to be protected. I also thought this rule only applied to digital audio and not analog audio. Nobody seems to have a complete handle on what's really going on here, but I did read that Microsoft and Cyberlink (the developer of PowerDVD) are trying to work together to get this resolved. Hopefully they'll come up with some solution so we can listen to the audio tracks from these discs in all their high resolution glory from our PCs.
'jdyoung75' commented that maybe people aren't even going to get 24bit/96kHz or 24bit/192kHz soundtracks anyhow because the movie studios will probably only provide at best 24bit/48kHz soundtracks. (Actually, I would probably be satisfied with that, but I'd still like to hear 24bit/96kHz surround and/or 24bit/192kHz stereo tracks for concert performances.) His post implies that since the studios aren't going to include anything with a sampling rate higher than 48kHz, then maybe the problem with PowerDVD downrez'g isn't such a big deal. They're still converting the bitdepth from 24bit to 16bit and I'd like to hear them in 24bit. He referenced an article that appeared in EngadgetHD that said the real reason is because of storage space. There isn't enough space to include the uncompressed high resolution audio. But that's why they use lossless compression like Dolby TrueHD and DTS-HD MA to give you the same high quality using less space. These losslessly compressed HD tracks should still maintain the same resolution of 24bit/48kHz or higher (if available).
Just to give you an idea of how much storage space you need for uncompressed HD audio files, take a look at the following chart:
As you can see, these HD tracks take up a lot of space. However, those numbers are for uncompressed audio. Don't get confused by the way they measure bit rate and storage size. When calculating the bit rate they refer to million bits per second (divide by 1,000,000) and for storage requirements, they refer to megabytes (divide by 1024 a couple times and also multiply by 8 bits to get a byte).
I don't know exactly how much space we'll save by using the losslessly compressed codecs. The only information I could find regarding the efficiency of these codecs was from this FAQ for Dolby's TrueHD. If I'm interpreting this correctly, with a 24bit recording, they achieve compression ratios of about 2 to 1, for a file size savings of about 50%. So we might be able to store 90 minutes of a 24bit/96Khz 5.1 surround sound track in 4.3 GB of space.
Since HD DVD has a storage capacity of 15 GB for single-layer and 30 GB for dual-layer discs (and 51 GB for single sided triple-layer discs); and, Blu-ray's capacity is 25 GB for single-layer and 50 GB for dual-layer, you'd think they'd have enough space at least for one of the losslessly encoded HD tracks.
'jdyoung75' commented that maybe people aren't even going to get 24bit/96kHz or 24bit/192kHz soundtracks anyhow because the movie studios will probably only provide at best 24bit/48kHz soundtracks. (Actually, I would probably be satisfied with that, but I'd still like to hear 24bit/96kHz surround and/or 24bit/192kHz stereo tracks for concert performances.) His post implies that since the studios aren't going to include anything with a sampling rate higher than 48kHz, then maybe the problem with PowerDVD downrez'g isn't such a big deal. They're still converting the bitdepth from 24bit to 16bit and I'd like to hear them in 24bit. He referenced an article that appeared in EngadgetHD that said the real reason is because of storage space. There isn't enough space to include the uncompressed high resolution audio. But that's why they use lossless compression like Dolby TrueHD and DTS-HD MA to give you the same high quality using less space. These losslessly compressed HD tracks should still maintain the same resolution of 24bit/48kHz or higher (if available).
Just to give you an idea of how much storage space you need for uncompressed HD audio files, take a look at the following chart:
| Bit Depth | Sample Rate | # of channels | Bit Rate (Mbps) | File Size for 1 minute | File Size for 90 minutes |
| 16bit | 44.1KHz | 2 (stereo) | 1.411 | 10 MB | 900 MB |
| 16bit | 48KHz | 2 (stereo) | 1.46 | 11 MB | 990 MB |
| 16bit | 48KHz | 6 (5.1 surround) | 4.6 | 33 MB | 2.9 GB |
| 24bit | 48KHz | 6 (5.1 surround) | 6.9 | 49.5 MB | 4.35 GB |
| 24bit | 48KHz | 8 (7.1 surround) | 9.2 | 66 MB | 5.8 GB |
| 24bit | 96KHz | 6 (5.1 surround) | 13.8 | 99 MB | 8.7 GB |
| 24bit | 96KHz | 8 (7.1 surround) | 18.4 | 132 MB | 11.6 GB |
| 24bit | 192KHz | 2 (stereo) | 9.2 | 66 MB | 5.8 GB |
As you can see, these HD tracks take up a lot of space. However, those numbers are for uncompressed audio. Don't get confused by the way they measure bit rate and storage size. When calculating the bit rate they refer to million bits per second (divide by 1,000,000) and for storage requirements, they refer to megabytes (divide by 1024 a couple times and also multiply by 8 bits to get a byte).
I don't know exactly how much space we'll save by using the losslessly compressed codecs. The only information I could find regarding the efficiency of these codecs was from this FAQ for Dolby's TrueHD. If I'm interpreting this correctly, with a 24bit recording, they achieve compression ratios of about 2 to 1, for a file size savings of about 50%. So we might be able to store 90 minutes of a 24bit/96Khz 5.1 surround sound track in 4.3 GB of space.
Since HD DVD has a storage capacity of 15 GB for single-layer and 30 GB for dual-layer discs (and 51 GB for single sided triple-layer discs); and, Blu-ray's capacity is 25 GB for single-layer and 50 GB for dual-layer, you'd think they'd have enough space at least for one of the losslessly encoded HD tracks.
Friday, October 12, 2007
Tchaikovsky SongSpot
It's been awhile since I updated my SongSpot. I don't know if anyone noticed, but they've improved the widget so you can now create a playlist of several songs. I did that with my last SongSpot which included songs from Billy Bragg, Elliot Smith and the Barenaked Ladies. However, I think I might prefer the single song approach unless they'd allow playback of full albums, but I doubt that will happen anytime soom. Anyhow, I decided it's time for an update so I went to Sonific's site to choose something. I noticed the list of "Most Played," so I decided to play a few to see what other people think are the best songs.
My first click was on Odessa Philharmonic Orchestra. This is really beautiful music. It's a live performance of Tchaikovsky's 5th Symphony at the Musikverein in Vienna from March 25, 2001 by the Odessa Philharmonic Orchestra, Hobart Earle, Conductor. Winner of the "Best Classical Album" Award at the 2002 Just Plain Folks Music Awards. Here's a link to the CD. Hope you enjoy it.
My first click was on Odessa Philharmonic Orchestra. This is really beautiful music. It's a live performance of Tchaikovsky's 5th Symphony at the Musikverein in Vienna from March 25, 2001 by the Odessa Philharmonic Orchestra, Hobart Earle, Conductor. Winner of the "Best Classical Album" Award at the 2002 Just Plain Folks Music Awards. Here's a link to the CD. Hope you enjoy it.
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