I have 7.1 system and am not sure which surround mode type to set the system to for tv and movies. Thanks.

To some degree, it comes down to personal preference - there isn't any one "right" answer. FOr what it's worth, here's what I do with my 7.1 system:

• DVD's: Dolby Digital 2.0 through 5.1 and DTS 5.1 get Pro Logic IIx in addition to the basic decoding (generating 7.1). Dolby Digital EX (flagged) and DTS-ES are required to use their respective processing modes, so there's no choice to be made there.
• Cable TV: Everything (PCM stereo, Dolby 2.0, and Dolby 5.1) gets Pro Logic IIx applied.
• Music: Both CD's and music from my SoundBridge M500 remains in stereo and gets upsampled.

In addition to the modes listed above, you also have DTS NEO:6 (which can be used with PCM stereo sources, analog stereo sources, and DTS 5.1 sources) and 7 Stereo (which can be used with PCM stereo sources or analog stereo sources) available to engage all seven speakers. Dolby EX can also be used with regular Dolby Digital 5.1 sources, but PLIIx will probably work out better for you overall.

I agree with Gonk,I myself use 7 channel stereo for tv and music, and dolby digital plus pro logic IIx for movies, on my 990 there seems to be more bass in 7 channel stereo, I think it comes down to what sounds best for you.

I often use DTS Neo:6 Music for CD's or radio if I want to engage the surround speakers. It tends to give you a wider sound stage with more mid-bass than ProLogic IIX. Prologic IIX tends to give you a more defined center than Neo 6 Movie mode so it often makes dialogue more intelligible.
I do vary from these norms a lot though depending on the source material.
I don't use Stereo 7 for critical listening, but it's the ultimate party mode for supplying music for multiple small conversation groups scattered about the room.
I fully agree with the others for stereo, the upsample is great.
Like most everything else in this hobby, it all boils down to trying all of the options and picking what you like for the particular recording and situation .

When listening to music, I use analog (stereo > upsample). It gives clearer sound. However, I have a problem when I watch movie. The surround sound mode is not what I'm expected. I have to turn volume all the way up for the sound (dolby, dts, pro logic), but stereo 5 channel is much better than the others. So my main surround sound for movie is 5 channel stereo. I think I read somewhere that if DVD player has Dolby Digital built-in, do not use analog cable to hook up; use digital cable such as Coaxial or optical. Can someone let me know what should I do to watch movie with Dolby, DTS surround sound. Other wise, I can still use 5 channel stereo to watch movie.

If you are using analog, have you tried bypass? It'll give a cleaner signal path - upsample (and all modes aside from bypass) convert the analog to digital and back again.

For DVD's, you do not want to use the stereo analog outputs - especially if you have a 990! Unless it is a very rare and unusual situation that makes the multichannel analog output preferable, I recommend using the coaxial or optical digital output from the DVD player to the 990 so that the 990 can decode the Dolby Digital or DTS formats. Stereo analog gives you a downmixed stereo track from 5.1 sources, which kills the intended surround sound experience. You will have to use a higher volume setting for DVD's than CD's or cable/satellite TV, but that's because of the DVD format: the audio is mastered a good bit lower to allow more headroom for dynamics. This is a good thing, as it allows for sudden changes in the soundtrack (explosions, for example) without the audio clipping. 5 Stereo sounds louder because your surrounds are operating at the same level as your mains, which is not typically done in surround mixes. It's a very different sound with the DD or DTS delivered to the 990 by coax or optical, but you really owe it to yourself to give it a try.

Gonk,
Thanks for your response. Somehow, upsample is better than bypass; I compared the two. On the surround mode, I did unplug the anolog cable, now dvd player connects to 990 via Coaxial cable.

I've tried different surround mode, and the Neo:6 Music is better. I don't know how many members here using Neo:6 Music for watching movies. If not, can you tell me what sorround sound mode are you using to watch movie?

Next, I currently using stereo cable (unbalance)to hook up my 990 and 7500. I don't have problem with this, I mean no hiss no hum. I don't know if I use balance cable, my system will perform better?

Man, I love my Outlaw more than I love my wife. If you're thinking about upgrade your system, don't buy A/V, buy separate and you can't go wrong.

If upsample sounds better than bypass, I'd seriously consider using digital output instead of analog - you're using the 990's DAC's anyway when using upsample, since using upsample with an analog stereo connection yields digital-to-analog at the DVD player, analog-to-digital at the 990, upsampling of that digital signal, bass management, and digital-to-analog at the 990. If you simplify to digital out of the DVD player, upsampling at the 990, and digital-to-analog at the 990, the results should be similar - and with the simpler path (eliminating both the player's DAC and the 990's ADC) very possibly better sounding.

If you are using NEO:6 Music with DVD's, there are two possibilities that I'd suggest might be worth changing. First possibility: you are still using a stereo analog connection out of the player for DVD's rather than the coaxial cable instead. Second possibility: you are using the coaxial cable but your DVD player's digital output is set to PCM rather than bitstream (or raw, as some players label it). I say that because NEO:6 can only be applied to a PCM stereo signal or overlayed on top of DTS 5.1 to produce a mono rear surround - it can't be used at all with a Dolby Digital source, which is the standard audio format for DVD's. You need to make sure that you have your player's digital output set to bitstream/raw to make proper use of your 990. If you let us know what player you have, we can probably help figure out exactly what setting needs checking.

If your connections between 990 and 7500 are working (as they are, based on your comments), I wouldn't change anything.

Gonk,
Correct me if I'm wrong. For music, analog stereo is better digital right? However, I will disconnect last stereo cable that I hook up to my 990 from my DVD player when I get home.

I set input for my dvd player to use Coaxial instead of analog. So it shouldn't use analog signal. The reason I use Neo:6 Music because it produced better sound (less volume) than other modes. I have to turn volume all the way up (almost +1 db) for the modest sound when using DD or DTS.

Last but not least, Sony is my DVD player. I use her to watch movie and music.

For music, I would put a very large qualifier on analog stereo being better than digital: analog stereo is only better if the source player's DAC's are better than the receiver/processor's DAC's. The 990 has some very good DAC's, and with a Sony DVD player I'd certainly expect them to be better than the player's DAC's. The fact that upsample sounds better than bypass with stereo analog inputs certainly hints at this. Keep in mind that the audio is starting out in the digital domain, and one of the strengths of a surround processor like the 990 is its ability to operate on data in the digital domain (both for surround processing and for other things like bass management, channel trim, speaker distance, and even upsampling). Leaving that digital audio data in its native start and getting it to the 990 in that form will more often than not be the optimal path to take.

If you are able to use NEO:6 with the digital input, that definitely points to a setup issue in the DVD player - that mode by itself should be available only with PCM sources, and I can think of only a handful of DVD's on my entire library that offer a PCM track anywhere on them (a few music discs that have PCM stereo and Dolby 5.1, and a few bootleg Star Wars movies), but the vast majority offer nothing but Dolby Digital with DTS as an option in some cases. The player's setup menu should have some options for digital audio output, possibly a single setting or a couple of separate settings (one for Dolby Digital and one for DTS). These settings need to be set to bitstream, and I'm almost certain that they are on PCM right now. The fact that you have to go to +1dB also suggests that the player has some volume control in play (and set fairly low) - changing to bitstream will bypass that volume control, as the player will no longer manipulate the signal at all. I don't have any Sony DVD player manuals in my PDF collection to know how they typically handle their player setup menus, but if you've got a model number I may be able to track down the specific manual for your player and help point you toward that setting.