ATI550 and NICAM sound overload ?

[LH.se]

Hi,

As a beginner on gbpvr (great software !!!), I have a question:

I'm using the Sapphire PCI ATi550 based analog tuner card, in kombination with a nVidia based 6600GT videocard and EMU-1212m soundcard.

I have distorsion on all my analog TV channels which has NICAM sound (there are no problems on mono channels). Is there any way I can adjust this, so that for example NICOM is not overloading so much ? When I look on my EMU control panel (EMU-1212m is a studio sound card wiht awsome specifications!) and it's "Peak Meter" I can see how it bottoms out at the same time as the sound get's distorted.So I guess that lowering the output with 6dB might do the trick, or maybe even 10 dB ?

Any ideas or thoughts are welcome !

[jamesb]

The drivers for the theater 550 have a audio volume setting in the filters. This would be useful if the distortion was occurring in the tuner instead of your sound card.

The negative part is that (at the moment at least) GBPVR provides no way to access the filters.

[LH.se]

I know it's within the Theater 550 that the distorsion occurs. No matter what I do I can't lower the "volume" from within the soundcard mixer board (and believe me, there is a lot of things I can do with the EMU-1212m - it's a so called "pro studio card" made for recording in very high quality )

[csy]

Is the volume actually overloaded, or could it be the ATI 550 card not centered on the NICAM carrier frequency?

GBPVR has a known issue on the 550 card where if you manually specify the channel frequency in the GBPVR config instead of using the tuning assistant, then the 550 card NICAM decoder offset frequency is wrong, resulting in distorted NICAM sound.

The fix is to use the tuning assistant and identify the channel numbers, and input those channel numbers into the GBPVR config (not frequencies).

[LH.se]

csy: Thanks for the tip. Jusst to clearify: I never used the frequency, I have always used the channel numbers. However I have never used the Tuning Assistant. Does the Tuning Assisten "store" the frequency somewhere so that GBPVR will reuse that information if I rescan all channels ?

The reason for asking is simple: I just did the scan within Tuning assistant and it made no difference. However, I think you are correct on the issue here - NICAM Carrier Freq. I just don't know how to proceed. Do I need to re-install or ?

[stefan]

Tuning assistant is not that automatic, but it will give you the frequency in order for you to manually enter it instead of the channel number in the capture source settings in the config app. Try with one of the channels first. You might also have to fine tune (manually) by lowering or raising the frequency in steps by 500 or so.

[LH.se]

Sorry, stil don't get it - If I enter the frequence I get static breakups in the sound - no matter if I add +/- 500.

Currently I'm running with forcemono=1 in direct.ini = no problems with sound, but it's not what I would like

[kaszika]

Hi,

I have bought Theatrix 550 this week. In my opinion this card simply does not support Nicam stereo. If you shift the frequency nothing change. You can shift up to your software change to mono mode, the noise disappired, and you would be happy, but it would not be Nicam stereo it would be mono!

[csy]

I can confirm that NICAM on the 550 card works perfectly in New Zealand (PAL-B/G), as default with no tweaking of frequencies.

[kaszika]

I have found the problem and the solution last night.
For example I have PAL B/G CATV here in Hungary. If I set Germany as a country where the standard and channel spacing the same as here, there would not be Nicam stereo. But If you check the country to Channel table list at http://msdn.microsoft.com/library/defaul...rrides.asp you would see there are countries where the system is PAL B, but because of the missing information Microsoft use Unicable Frequency Table for these countries cable tv channel list. For example New Zealand and Norway. If you set one of these country in your program, you would have Nicam stereo!
Then if you would like to have Nicam stereo with ATI 550, you have to choose a country, where the colour standard (PAL/Secam) and the sound standard (B/G, D/K) is the same as your country, but at the CATV channel spacing you find F_UNI_CABLE. I hope I was clear enough.