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Join Date: Jan 2003
Location: Portland, Oregon, USA
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Thanks to pdxfj for bringing in his RS4910 for us to test here at Lumagen.
We have not yet loaded the very latest JVC software update mentioned above by pdxfj, and still are finding that pdxfj's JVC RS4910 and the Radiance 2041 are working well with each other. We are testing with several different long HDMI 1.4 2k rated cables and a 50 foot Monoprice Redmere 4k rated to both the JVC inputs from the Radiance 2041 the JVC and Radiance at 1080p60 and 4k24, and switching between these modes. If we can't reproduce any issues here it may come down to HDMI cabling in any problematic system.
We will continue testing the RS4910. If you have a specific sequence of events for us to test, please let us know.
We will post results here, probably on Thursday since we only have the RS4910 until then.
I have posted the following elsewhere but for completeness think it is appropriate for here as well:
The Lumagen Radiance 20XX units use 4K HDMI output chips. These have faster edge rates. “Transmission Line Theory” clearly states that the faster the edge-rate of the signal the better the transmission line environment must be. This translates to the quality of the HDMI cable and, yes, it means that you may very well need better HDMI cables for devices with 4k rated output chips, verses devices with 2k rated output chips. Edge rates will vary between chip manufactures. So, HDMI cable quality demands will even vary between different 4k rated HDMI output chips.
This is specific to the output chips edge rates. We have had several customers who needed to switch to 4k rated cables for the Radiance 20XX series. This is a matter of physics and applies whether you are driving a 2k TV/projector at 2k, or a 4k device at 4k. Because of this, Lumagen strongly recommends 4k rated HDMI cables from the output of the Radiance 20XX series to the TV/projector or Audio processor. We have found the Monoprice Redmere active cables work very well with the output of the 20XX series.
In addition, as always, standard HDMI cable rules apply. These include never using an HDMI cable less than 6 feet (2 meters), due to HDMI cable EQ making short cable signals too hot in many cases. Sometimes lengthening a 2 meter cable to a 3 to 5 meter HDMI cable will help if there is quite a bit of cable EQ. As cables approach 30 feet (9 meters) cable length makes HDMI cable quality (including speed rating) and the HDMI receiver’s design critical. Since every HDMI connection will have some level of Transmission-line reflections, which can cause nodal points based on cable length, changing to a slightly shorter or slightly longer cable can move the cable nodal response away from critical failure points.
Try several different brands of HDMI cables if there are issues. At this length differences in manufacturers cable EQ (transmitter and receiver) and speed ratings (2k or 4k) make a significant difference.
Be cautious with name-brand cables. Users have seen issues with some of the more expensive brands. Of course many high-end HDMI cables work well, but why pay more for the same "bits" coming down the wire. Unlike analog cables, the bits are either passed exactly (e.g. solid picture) or they aren't (e.g. sparkles, drop-outs, etc.). Our customers have had good results with Monoprice, DVI Gear, or Bluejeans HDMI cables. For the Mini, XS, XD, XE 2K rated cables work well, but for Radiance 20XX units, please make sure to use 4k rated HDMI cables on the 20XX outputs to either a display or audio processor.