Archive for July, 2009

vista sound for htpc

July 30, 2009

I have spent quite a bit of time on my vista media center’s audio setup. (Too much time really.) One of the things I am doing that most folks do not is that I am processing the audio inside the computer and outputting the analog channels to amplifiers directly. For me this setup works great.. I don’t have a fancy receiver that’ll do the processing that I want all in one place, so what I did was buy several older receivers that do not support DD or any of the latest stuff (because they are very inexpensive now). So there’s one running the mains, another running the two center speakers, one for the rears, and of course I have my sub amp already. Long term my goal is to replace these older receivers with some nice amplifiers.

Anyway, there are a few gotchas that I have learned while doing this, and I will attempt to list (some of!) them here.

  • “Select Full Range Speakers” during Vista speaker setup

This one seems easy.. i have full range speakers in front and rear, so that seems like the thing to check.. unfortunately, this is not the case. If you read this blog entry carefully, you can see that what happens when you check this box is “In other systems, people who prefer full-range loudspeakers in some or all positions may not have—or want—a subwoofer. In such cases, material intended for the subwoofer in home theater systems may need to be mapped back into the main channels so that it is not lost. Such a scheme of bass management is referred to as "Reverse Bass Management", as shown in the following illustration.”.

If you read that carefully, you can see that selecting “full range” speakers sends the bass intended for the sub out to the speakers you check. In a home theater setup with a sub, this is not good.

  • If you have 64 bit vista installed, you will need 64 bit codecs. This one also seems rather obvious after you know it, but it can trip you up if you aren’t looking for it.
  • The best way to get the codecs that you need and will work is to use the  Vista codec pack by shark007. Of course, don’t forget that if you are running x64 to download the x64 components.
  • Understand that audio filters, presets, environmental effects, etc, can be stacked , meaning that if you enable, say “expand stereo” in the card’s driver settings, you don’t want to enable it in ffdshow, or it will try and do this twice. This is bad! Another one that will cause issues is the “bass management” setting. The best thing I have found to do is go to control panelsoundspeakers and check “disable enhancements”.
  • I have also had issues with “enhancements” being enabled, but none of them being used, and this can cause crackling and popping in the sound. As I said above, just disable them, save yourself the trouble.
  • If you have a motherboard with the “nvidia nforce 4” chipset (like my Asus A8NSLI Deluxe), you do not want a creative  soundblaster xfi card. There are known issues and it may or may not work, and you won’t know until you have problems.
  • I constantly have problems with the “creative audio control panel”, and if you download the drivers from creative, you can’t get ones without it. So what I have found is that if you get the driver, download, install, etc, then you can uninstall the control panel stuff, and that will leave the latest and greatest audio driver without all of the other crap they like to “give” you.

OK, that’s it for now.


hyper-v networking

July 23, 2009

(I hope to start making more of these type posts of weirdness I find, but this is a first.)

We were having what I thought were network issues at work, so I started a pingplotter on my XP vm on my hyper-v server at home. Based on the graphs below, things look pretty latent.

If you run the same thing on a physical machine on the same network, the graphs look much better, and you can see that the network is not the problem.

The takeaway here I guess is to be careful with this sortof thing. Right now I’m not sure if it is a hyper-v specific thing or if it’s just a vm in general.