August 2008

Audiolics Anonymous Chapter 106
Home Theater Computer Pt. 3
Article by Dr. Bill Gaw

  As you read this it's probably August, and hotter than hell. With those tube amps fighting your air conditioner for temperature regulation, and the beautiful evening weather,  you're probably spending less time listening than you would in the dead of winter when those amps keep you nice and toasty. Also, tweaking of your system is probably taking a back seat to keeping the swimming pool clean and free of algae. That's okay as we can't spend all of our free time on our audiophile hobby.

On the other hand, during those rainy or those super hot days, wouldn't it be nice to go down to the basement workshop where its nice and cool and build a CD playback unit that will beat anything out there for less than $5-10,000 that will cost at the most only a few hours and $1000 or so dollars? Please review AA Chapter 101 and AA Chapter 105 before continuing on today with my discussion of home theater computers.

I've finally completed my work on my own Memory Player, developed by Y.N. of Israel, and can truthfully say that it has met all of my expectations. I won't go into the myriad pages of information he has left on his web site for how he prefers to build the unit, which is very similar to the minimalist approach which most high end companies take with their equipment to decrease complexity and its possible degradation of the signal, as his instructions are precise, concise and brilliant in their execution. On the other hand, being the tweaker that I am, and needing the unit not only for two channel CD playback, but also for DVD-Audio, DVD, Blu-ray and HD-DVD playback, I've modified the construction to fit my pocketbook and playback options.

Hardware
Instead of using his Zalman chassis with its 7-inch LCD screen and constructing the unit from parts, a brand new Hewlett Packard Model 8167 desktop tower was obtained from a discount house called ECost for only about $850. This unit was ideal for my use except for its upright chassis, having the following included for a ridiculously low price:

a. Core two Quad 6600 2.4 GHz processor for super fast playback, recording and processing of high definition video. This goes against Y.N.'s idea that the simpler and slower the processor, the less noise is produced inside the computer, but this is balanced by it being able to use one of the memories for CD playback while all housekeeping functions are carried out by one or more of the other cores.

b. Asus P5BW-LA motherboard. This has two advantages. First, it has six SATA connectors which allows one to have this rather than USB or Firewire transport of information. Second, with its Realtek ALC 888S chipset and programming, it can support up to 8 channels of high definition audio.

c. 3GB of PC2-5300 MB/sec 240 pin, DDR2 SDRAM. Again, possibly overkill for CD and possibly adding noise to the system, but perfect for playback of 24/88 or 96 files that require more bits for RAM loading than 16/44.

d. 2.4X HD-DVD ROM drive. This was the one failing of the original computer as HD-DVD is no more. On the other hand it is a superb drive for copying CD information to the computer as it is extremely accurate in picking up the bits.

e. LG GGW-H20L 6X Internal Super Multi BLU-RAY Disc Rewiter & HD DVD-ROM Drive was added to give playback of all disc formats (except for SACD of course).

f. Wireless LAN 802.11 b/g for connection to the web for software updates and buying those high definition audio files that are becoming available on the web.

g. Bluetooth (Integrated) This allows use of a portable keyboard and mouse for control of the computer from the listening chair.

h. GeForce 8400GS Graphics Card with built-in HDMI output for direct transmission of  high bitrate high definition audio and video to an external preamp-processor.

i. Memory Card Reader supporting all formats to allow transcription of all video and audio files easily between the computer and outside playback devices.

j. Two 300 GB 7200 RPM SATA hard drives. One is used exclusively for programs and Vista with the other for storage of about 1/3rd. of  my CD collection.

k. NTSC TV- FM Tuner Card

Of course modifications in addition to the Blu-ray HD-DVD drive were done as follows:

a. Removal of Modem Card. This was not needed and added unnecessary noise.

b. Removal of NTSC TV-FM Tuner Card, as NTSC TV will be discontinued as of January, card space was needed and tuner cards create much noise.

c. Addition of 4 port SATA Card. SATA is the newest form of connection to the motherboard, which runs cleaner and faster than either FireWire or USB. This allows one to run external hard drives. While this connection may not be as quiet and jitter-free as using the motherboard SATA connectors, it does have the advantage of being able to easily use low noise external power supplies and only need to be turned on when their data is being used, thus significantly cutting down on both mechanical and electrical noise to the computer. Plus, the drives should last longer as they are only running when being used.

d. Addition of 4 500 gig 7200 RPM SATA External Hard Drives.

1. #1 for my transcribed 24/88 vinyl files

2. #2 for my 300 CD collection at 16/44

3. #3 for my transcribed 250 16/48 DAT collection of 1/2" analog tapes from studio masters.

4. #4 for storage and playback of video.

e. PINNACLE PCTV HD PRO STICK. Reviewed last month, AA Chapt 105. A wonderful little USB add-on ditzel that will allow recording of both NTSC and ATSC high definition television, cable TV and FM through RG cable or S-video or composite video signal. It has the advantage over a computer card of not taking up a slot, not having to be continuously on producing noise while one is listening to music, and being able to use it on other computers such as a laptop.

f. Bluetooth wireless keyboard and mouse.

Software
Unhappily, there is no one audio program that will do everything that one needs for high end audio playback of all disc types. Therefore, one needs to mix and match depending on one's playback preferences.

1. Operating System; While many people prefer Mac computers for their ease of use, especially professional sound and video specialists, most of the world uses Windows operating systems, or possibly Linux. Also, while XP has been around for a long time and most of the kinks have been worked out, I prefer

a.  Windows Vista Home Premium with Media Center.  Vista has two very big advantages over XP; the elimination of the so-called Kernal Mixer which destroyed fidelity unless one used ASIO playback, and its built-in ability to play back high definition files with the proper software. Media Center, while klunky in operation, is free with Vista, and will allow you to listen to TV, Radio, and DVD's without any added expense.

2. Audio-Video Software: Unhappily, Windows itself doesn't have the ability in itself to correctly play back regular PCM 16/44 files, never mind high bit recordings and high definition video and DVD-A so one does need to spend a few extra dollars on additional software.  Therefore, which of the following software you'll need will depend on your listening and watching preferences.

a. Windows Media Player is actually not the best out there, but free.

b. Winamp is very nice free audio player with a gazillion plug-ins to adjust the sound in any way imaginable. While most of the plug-ins are worthless, either just changing the look of the thing or adding changes in the sound that are worse than worthless, by itself a very easy to use audio playback system.

c. MediaCenter 12; developed by J. River, is far superior to Media Player, adding DVD ( and Blu-Ray file playback with proper add-on software), 24/88 ripping, burning and playback, TV recording and playback with proper input card, organization of all sorts of playback media far better than Windows Media Center, transposition of different file formats, for instance PCM to MP3, and networking ability. Its most significant advantage for audiophiles is its multiple digital signal processing abilities including upsampling to 24/192, digital equalization, and ASIO playback. The only negative is its inability to do RAM playback. At $39.95 a reasonable value for a quality product. Unhappily, it won't do DVD-Audio, Blu-ray or HD-DVD playback.

d. Cyberlink Power Director 7 is one of the best programs for creating DVD's, Blu-Ray and AV-CHD disks. It's easier to use than most products out there, and allows one to burn 25-50 gig high definition discs for backup and storage. While this doesn't sound like anything for audiophiles, using another product we'll be discussing next month, I've been able to archive some DirecTV high definition programs of music concerts to Blu-ray discs, thus freeing up hard drive space on the DirecTV receiver. More next month.

e. WinDVD 9 

f. cMP Memory Player; This and the following software, developed by Y.N. of Israel, are the two most important for high end audio playback. It can be download here, allows two big advances:

1. The ability for it to run the computer, shutting down Explorer and several other RAM hogging Windows sub-programs.

2. Disk traffic interference during playback is eliminated. Advanced RAM playback is based on system's available physical RAM (as reported by Task Manager or Process Explorer. cMP achieves memory playback via the system cache and not through a simulated virtual drive. This approach removes Windows disk I/O overheads (irrespective of whether disk is physical or virtual) hence, it's more optimal.

Through the above, bit perfect delivery is claimed yielding an ultra high resolution of more than 23.5 bits to an internal DAC. The program also loads CD's from discs to a hard drive for storage, and during the process keeps rereading the information until it is as close to bit perfect as possible. Most discs are read at 2X, thus taking about 30 minutes, but many of my older ones took upwards of 2 to 3 hours, showing that "Perfect Sound Forever" is a misnomer in more ways than one.

g. cPlay is a minimalist audio player using the latest high quality SRC upsampler offering state-of-the-art ASIO-only playback with a signal to noise ratio of 121 dB. cPlay loads entire .wav or cue. files into RAM before starting. Playback is done directly from cPlay's internal buffer which can support files up to 2GB. Upsampling up to 24/192 is done by the program as is volume control in 0.5dB steps at 64 bit precision."

RAM loading of a 640 mB CD takes about 15 seconds from the hard drive, and the information is then upsampled by the program to the highest allowable amount for your DAC or 192 kHz.

This is a superb program in that it is free (you can't beat the price), it is fast to download and set up, and it works as described. All files and CD's are downloaded to RAM before playback to minimize noise, jitter, etc., and then it can either be transferred digitally by the soundcard to an external D/A converter using ASIO, or converted by the soundcard to analog for playback. With XP and earlier Windows iterations, the K mixer with its 48 KHz. transcoding is eliminated, and at the same time the program will upsample 16/44 to a maximum of 24/176 or 24/192.

It produces the cleanest most analog sound I've heard from 16/44 files, which is saying something as many of the other programs available can also do DSP to sweeten digital. Also, as it has been developed by the same individual who produced cMP, it can be used inside that program's shell, eliminating many of the Window's programs that run automatically which are unnecessary for audio playback and cause problems with the soundstream.

It's one major drawback for Windows Vista, which already circumvents the K mixer so that ASIO is not needed, is that one cannot get the advantage of RAM loading as the program requires using ASIO unless one uses an external D/A converter as Vista enabled motherboard audio programs will not load ASIO.

HTPC Problems
Now to the major problems associated with using a  home theater computer  as your audio-video source and processor;

a. Windows is a pain in the ass. While one can usually leave Vista running for days without screw-ups that required rebooting, every once in a while I still can get the "Blue Screen of Death" when the computer gets so frazzled that it shuts itself down, usually in the middle of something being working on and not saved.

b. Hard Drive Failures. In the past month two of my older hard drives have failed. Luckily, the one with all of my original family photos that I had spent hours digitizing had been cloned, and a local computer repair service was able to save most of the family 8 mm films from the 60's that had been stored on the second one. Unhappily, it cost more for them to do that than it would have to purchase 1 TB. of drives for backup. So at less than $200 for a terabyte of storage, remember to doubly backup everything worth saving.

c. M-Audio FireWire 410 Failure.  Last week, my FireWire 410 external processor that I had been using to play back my audio files using the C-Play program went on the Fritz. While it was receiving the digital information and processing it correctly, it would not transmit the digits to my Lexicon processor for D/A conversion. Interestingly, it functioned perfectly on another computer, so there must be some screw-up in either it's or Vista's programming. Guess I'll be fiddling around for a while trying to figure out which.

So while a Home Theater Computer,  when done properly, could replace all of your digital sources in one box, with high end reproduction of both audio and video, with the ability to upgrade systems or capabilities without having to buy a whole new piece of equipment, it still has a ways to go with reliability. On the other hand, so does a large percentage of audiophile-grade components, which tend to self-destruct or need to be updated on a regular basis at significant expense. More next month.