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04-17-2006, 11:35 AM
I will be getting the new Pana 50PX60U in a week. I am also buying a new reciever. I notice that the new Yamaha RX-V2600 has up conversion capabilities (according to they marketing materials it will upconvert all signal to the 1080i regardless of the input cable and source.)

My question is: Is it better to just let the Pana handle the upconversion based on the source or does an Yamaha buy me any advantages, i.e., better video quality for VHS and Hi-8, less changing of formats, etc.

Has anyone done this with there Plasma.

P.S. I am aware some cable boxes don't work with the amps yet because of the security coding.

Tks Tony

04-17-2006, 12:47 PM
This situation allows you the perfect opportunity to experiment with processing from a number of sources--DVD, receiver, STB, and plasma--but here are a few ideas. First of all, you're getting a terrific plasma, but I don't believe that video processing/scaling is necessarily its strongest suit. What the Panasonic may lack in that dept., however, might not be immediately, or ever, a problem for you. The kinds of errors to look for are jagged edges, line twitter, noisy/grainy patches, color bleeding, and creeping edges. You may notice it more with video material than film material, since the former is harder to deinterlace, or you may not notice it at all unless you run dedicated tests. Sometimes mediocre signal processing can result in little more than a soft picture to most eyes, which might not be evident without immediate comparative processing from another component.

If this plasma model scales everything to 1080i before converting to its native resolution (1366x768 in this case), as other consumer Panasonics have done in the past, having the Yamaha do the job instead might pay dividends. Yamaha's projectors normally scale and deinterlace very well. If the receiver uses the same chipset as Yamaha's own video equipment, it could get to 1080i better than the Panasonic does before its ultimate destination of 768p. However, if the Panasonic processes all signals democratically to its native 768p (as I suspect that it does), the Yamaha's upconversion would have little value with SD, 480p, or 720p, since all of these signals would have to undergo two stages of processing--by the Yamaha to 1080i and by the Panasonic to 768p--which is rarely a good thing.

If your STB or satellite receiver forces a choice between 1080i and 720p for hi def broadcasts, you could give both options a try, with and without Yamaha upconversion in place (I assume that it is defeatable). Who knows how good the tuner will do its job relative to the other components, or whether the Panasonic will react better to true HD (not upconverted) signals at 720p than to true HD signals at 1080i. You can see how complicated this testing can get. I wouldn't blame you if you didn't have the stomach for it

If your DVD player upconverts to 720p or 1080i, try every option that your sanity and patience allows, including just sending 480i through to the Panasonic. The problem with upconversion is that it often isn't extensive enough. If your DVD player, STB, and receiver upconverted to 768p, then these comparisons would be much easier. Why on earth does this Yamaha receiver include scaling and deinterlacing in its video section? Right, because it can.


04-18-2006, 01:08 PM
The receiver: (taken from company site)
High Picture Quality

Fully Analog Video Up-Conversion to HDMI and Component Video
Output with TBC
De-Interlacing (480i to 480p)
Up-Scaling (480i to 1080i/720p)
Wide-Range Video Bandwidth (100MHz -3 dB)

The T.V. doesn't list any kind of conversion specs. I would guess that it relies on an HDMI source already being 1080i or up-converted already, right? I know that a 480i signal (direct in from sat) on these t.v.'s does not appear to be upconverted, by that is just judging by sight and not fact.

The only part that puzzles me is that the Yamaha lists fully analog HDMI upconversion, I had thought that HDMI was either D-D or in some cases A-D. I hope this helps. I am interested to know the results.

04-18-2006, 02:24 PM
The plasma will upconvert or rescale every signal that it receives via HDMI or any other input that doesn't match its own native resolution, which is just about everything, since no unprocessed sources are 768p except for a few upscaling DVD players and better processors. This isn't an option for the TV; it is a necessity. It must upconvert any signal that enters it at 480i or worse to 768p to display it at all--no exceptions. Not every instance of this processing may not look very good, depending on the quality of the source and/or its processing.

The analog upconversion to HDMI that the Yamaha claims to do refers to the composite, S-video, and component feeds that it changes to digital HDMI as a convenience. It cannot change the resolution of the original analog signals but it can reconsititute them as digital and apparently scale them to a higher format (1080i or 720p) and apparently deinterlace them. This is a job that microdisplays and many DVD players also do routinely. External processors can add much more elaborate options to these basic features.