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suburban
currently looking for a STB to compliment my TW600 projector. As the PJ accepts HDMI ill obviously source a STB with the same inputs.

So far looking around ive only seen a few with said connection - can anyone reccomend some models so i can start searching more thoroughly ?

cheers
Peter D
If you dont need the audio going to the projector, DVI and HDMI are effectively the same.
suburban
hmm thanks for that info peter, ill keep that in mind
sorcyone
QUOTE (Peter Dewildt @ Feb 10 2006, 11:52 AM) *
If you dont need the audio going to the projector, DVI and HDMI are effectively the same.


Assuming the 2 devices use compatible protocols. There are many STB out there with problems at different resolutions between DVI and HDMI. HDMI to HDMI you have fewer problems.
InTune
QUOTE (sorcyone @ Feb 10 2006, 12:19 PM) *
Assuming the 2 devices use compatible protocols. There are many STB out there with problems at different resolutions between DVI and HDMI. HDMI to HDMI you have fewer problems.


May I make a couple of comments:

1. Take it from me and a couple of friends who have HDMI enabled devices: The HDMI connector is physically a sub-standard design, flimsy and prone to all sorts of mechanical issues. The approved design includes a securing metal clip as an option to secure the plug to its socket but I have not yet seen any manufacturer that has implemented this option on AV gear. The HDMI plug can very easily be dislodged from its socket and is prone to poor contact connectivity due to its high contact density. It definitely does not inspire confidence.

2. The DVI socket/plug design on the other hand is more sturdy, it may be 'chunky' and only includes video but with good reasons! It is also the preferred option of high-end AV gear manufacturers but unfortunately, pressure exerted by HDMI 'fans' is pushing for a global HDMI adoption (with much regret).

3. If you have the choice of HDMI and DVI on your device always go for DVI for video and use the coax or TOSLINK digital audio socket for your audio.

4. HDMI<->DVI adaptors if required are available (they are electrically compatible FOR DIGITAL VIDEO only, ie. you will loose the HDMI audio on the DVI side and you will loose the DVI analog video on the HDMI side).

As a side note, a friend of mine just purchased a new 1200x1920 LCD display with HDMI connectivity and ... the HDMI connection gives a horrible picture! He is now enjoying excellent picture quality through the Y/Pb/Pr component connections.

Note that there is a lot of hype about DVI/HDMI digital connectivity but just consider these:
Most people think the digital connectivity provided by DVI/HDMI eliminates a lot of additional circuitry and signal conversions for digital-to-analog processing that is no longer required. However, this is not quite true as for the digital signal to be compatible with the DVI/HDMI standards it requires extensive digital re-processing at very high frequencies (in excess of 250MHz) to separate the single digital video streams into 3 (for single TMDS channel) or 6 (for dual TMDS channels) digital streams for DVI/HDMI transmission (via very expensive cables might I add). It involves A LOT of additional and very complex circuitry (with a lot of opportunity for things to go wrong - and they do!). Remember that this additional processing in the digital domain is performed at BOTH ENDS of the cable! I could also give you a few truths about DVI/HDMI cables that may be a little upsetting for some (the short version is that you'd have to spend mega bucks for a good quality 'digital' cable and they are still hard to find and there are a lot of resellers out there that will sell you a poor performing sub $200 cable for $400 and more!) - but that will be for later!

Component connections on the other hand do require D-A and A-D conversions but new chips are performing these functions extremely well these days. The 3 component cables only have to carry a approx. 50MHz bandwidth analog signal each, which are well within the capabilities of the humble 75-Ohm coax over reasonable distances (well over the DVI/HDMI zone of 'reasonability'). In a good setup (with properly terminated good coax) you'd be hard pushed to see a visual difference in the video between DVI/HDMI and Component (not composite!) connectivity (using good quality gear with good quality A-D and D-A conversion stages for Component video eg. from Denon, B&O etc ...).

InTune
sith
QUOTE (InTune @ Feb 10 2006, 05:50 PM) *
May I make a couple of comments:

1. Take it from me and a couple of friends who have HDMI enabled devices: The HDMI connector is physically a sub-standard design, flimsy and prone to all sorts of mechanical issues. The approved design includes a securing metal clip as an option to secure the plug to its socket but I have not yet seen any manufacturer that has implemented this option on AV gear. The HDMI plug can very easily be dislodged from its socket and is prone to poor contact connectivity due to its high contact density. It definitely does not inspire confidence.

2. The DVI socket/plug design on the other hand is more sturdy, it may be 'chunky' and only includes video but with good reasons! It is also the preferred option of high-end AV gear manufacturers but unfortunately, pressure exerted by HDMI 'fans' is pushing for a global HDMI adoption (with much regret).

3. If you have the choice of HDMI and DVI on your device always go for DVI for video and use the coax or TOSLINK digital audio socket for your audio.

4. HDMI<->DVI adaptors if required are available (they are electrically compatible FOR DIGITAL VIDEO only, ie. you will loose the HDMI audio on the DVI side and you will loose the DVI analog video on the HDMI side).

As a side note, a friend of mine just purchased a new 1200x1920 LCD display with HDMI connectivity and ... the HDMI connection gives a horrible picture! He is now enjoying excellent picture quality through the Y/Pb/Pr component connections.

Note that there is a lot of hype about DVI/HDMI digital connectivity but just consider these:
Most people think the digital connectivity provided by DVI/HDMI eliminates a lot of additional circuitry and signal conversions for digital-to-analog processing that is no longer required. However, this is not quite true as for the digital signal to be compatible with the DVI/HDMI standards it requires extensive digital re-processing at very high frequencies (in excess of 250MHz) to separate the single digital video streams into 3 (for single TMDS channel) or 6 (for dual TMDS channels) digital streams for DVI/HDMI transmission (via very expensive cables might I add). It involves A LOT of additional and very complex circuitry (with a lot of opportunity for things to go wrong - and they do!). Remember that this additional processing in the digital domain is performed at BOTH ENDS of the cable! I could also give you a few truths about DVI/HDMI cables that may be a little upsetting for some (the short version is that you'd have to spend mega bucks for a good quality 'digital' cable and they are still hard to find and there are a lot of resellers out there that will sell you a poor performing sub $200 cable for $400 and more!) - but that will be for later!

Component connections on the other hand do require D-A and A-D conversions but new chips are performing these functions extremely well these days. The 3 component cables only have to carry a approx. 50MHz bandwidth analog signal each, which are well within the capabilities of the humble 75-Ohm coax over reasonable distances (well over the DVI/HDMI zone of 'reasonability'). In a good setup (with properly terminated good coax) you'd be hard pushed to see a visual difference in the video between DVI/HDMI and Component (not composite!) connectivity (using good quality gear with good quality A-D and D-A conversion stages for Component video eg. from Denon, B&O etc ...).

InTune


I agree with InTune completely. I have experienced the same problem first hand recently. I bought a Pioneer 50" plasma recently and ordered a Toshiba c26H set top box with HDMI. As the set top box was not available for delivery the company gave me a Panasonic hdt105 set top box on loan with component connection. We used it for 1 month and the video quality was perfect. When the Toshiba set top box arrived and when I connected with monster HDMI cables - we could clearly see the difference. The images using HDMI were not as sharp, the colours were dull and artificial and the contrast appauling. Even the trial HD transmissions looked much inferior to the SD channels received by the Panasonic set top box!
As InTune mentions, we could clearly sense the amount of complex "digital processing" going on in the Toshiba machine through the HDMI circuit and how inferior it is to just a simple conversion at the component cable ends. I think the amount of digital processing makes the images TOO ARTIFICAL similar to digital manipulation of our digital photos with a software program. This is my first hand experience after 1 month of use and not a simple snap shot comparison in the shop.
I am returning the HDMI set top box and am going back to the component connection with Panasonic hdt105. May be once the HDMI standards improve I will get back to the HDMI circuit.
suburban
hmm thanks for that info guys. Im running component to my projector atm and the quality is great as is, dont see how the HDMI could improve on an already top picture....

something for me to consider smile.gif

thanks
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