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Interesting especially (to me) the unexpected jrp positive response about power supplies.

Is there such a thing as a power supply noise generator? ...
I have always said that I believe a linear power supply could improve audio. This has not changed. Back in the 1080p days I was skeptical it would improve video. Now for 4k, while still somewhat skeptical about video, I believe there is the potential a better power supply could help video when the underlying display technology is analog (DiLA, LCOS, but not DLP). The improvement might not even be visible at viewing distance though. That is why I add it may help. I do not want to discount it completely, and there may be a visible at viewing distance improvement. People need to test for themselves in their system.

There are noise injectors, but I think the time spent would not yield much. Choose a linear power supply. Then compare audio and video using the Radiance Pro digital power brick, versus the linear power supply, and judge for yourself. I can be pretty certain some will say "no difference" and some will say "there is a difference." I believe the people who say they hear/see a difference, and I believe the people who say they don't. It is after all system and listener/viewer dependent.
 

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Is there such a thing as a power supply noise generator?
If defined noise types could be used as input and compared that might be helpful to show the thresholds and video our audio changes such noise would impart.
These sort of things do exist, they are very expensive, but there is a further issue in that it doesn't stop there; the thing you need to measure is a few steps down from the thing that injects interruption or noise into the PSU, and the gear that could measure the HDMI (or even further downstream, DA output of a processor) with enough accuracy to pick up differences is also very expensive.
if you're wanting to get to the point of analysing the 18G HDMI at the wire level plus the impact on DA conversion you're probably into $100,000+ of T&M (test and measurement) gear.

I would consider a Lumagen matching rack sized power supply. But wouldn't want to overspend on it.
They're such niche product that you'll almost certainly be overspending by some definition. Maybe if you have an old 1U case, some time at a weekend and some electronics know-how it can be a nice DIY project for not mucho bucks spend, but if your time is valuable it's probably still mucho money in opportunity cost.
 

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Hi Jim:

Is it possible to display the BER counter in the Radiance Pro info screen?
No. Sorry.

Note that a BER counter for the Pro output would need to be in built into the projector/TV. Not simple to do and not going to happen.
 

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There are noise injectors, but I think the time spent would not yield much. Choose a linear power supply. Then compare audio and video using the Radiance Pro digital power brick, versus the linear power supply, and judge for yourself. I can be pretty certain some will say "no difference" and some will say "there is a difference."
The fundamental issue is, for those that say they can see a difference, is they are likely not doing blind A/B testing. Therefore, expectation bias is massively clouding the results of the comparison.
 

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The fundamental issue is, for those that say they can see a difference, is they are likely not doing blind A/B testing. Therefore, expectation bias is massively clouding the results of the comparison.
For what its worth.....

I am one who will say i DO see a visual difference.

I am "Extremely" sensitive to any extraneous image "noise" .....there are clips/scenes i have looked at hundreds of times doing comparisons with the Lumagen, madVR Envy and madVR HTPC.
When i installed the Up-Tone Audio LPS with my Lumagen, from my experience i have no doubt it improved not only the Audio but the Video.....
 

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No. Sorry.

Note that a BER counter for the Pro output would need to be in built into the projector/TV. Not simple to do and not going to happen.
Got it; the HDMI protocol does not contain any kind of link quality report backwards to the source unit ... :(
 

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At the risk of starting a mud throwing contest, any comparisons, short of side by side, should be done where the viewer does not know what option they are viewing (eliminates expectation bias).
I agree.

You really need to disconnect the setup not in use (to prevent noise in the non-active setup affecting the active setup), and so an immediate comparison is not easy to do.

I find this delay in the comparison is not a problem for audio. The couple minutes it takes to switch the configuration and listen seems to not dim my memory of the sound for comparison. As a "2-channel guy" I did a lot of this back in my 2-channel days.

However, in looking for differences in video I find it difficult to say for sure if one image seen a couple minutes prior is better/worse than the one I am viewing. As always this viewing must be at viewing distance on active content or the results are moot.
 

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For what its worth.....

I am one who will say i DO see a visual difference.

I am "Extremely" sensitive to any extraneous image "noise" .....there are clips/scenes i have looked at hundreds of times doing comparisons with the Lumagen, madVR Envy and madVR HTPC.
When i installed the Up-Tone Audio LPS with my Lumagen, from my experience i have no doubt it improved not only the Audio but the Video.....
I would love to see a comparison, where some test material is inputted to lumagen, then the output signal is analyzed and recorded. Then change the PSU(or hdmi cable for example), and compare the results. Comparing the results should be easy, since the pixel values are all digital and differences should be seen. I believe @madshi did something similar when testing an input card.
 

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For what its worth.....

I am one who will say i DO see a visual difference.

I am "Extremely" sensitive to any extraneous image "noise" .....there are clips/scenes i have looked at hundreds of times doing comparisons with the Lumagen, madVR Envy and madVR HTPC.
When i installed the Up-Tone Audio LPS with my Lumagen, from my experience i have no doubt it improved not only the Audio but the Video.....
What DC cable is required for the Lumagen RP? There are 5 cable choices with the JS-2.
 

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I would love to see a comparison, where some test material is inputted to lumagen, then the output signal is analyzed and recorded. Then change the PSU(or hdmi cable for example), and compare the results. Comparing the results should be easy, since the pixel values are all digital and differences should be seen. I believe @madshi did something similar when testing an input card.
Unfortunately this is an overly simplistic, commonly held view of the world, that digital means no difference in outcome is possible if only you can clock back in the same bits, for you cannot enjoy those digital signals as-is. This generally hold true in computer science where things stay digital, and the education of the masses in such technology has led them to a welcome yet incomplete understand of "Digital". Until you get a digital interface card for your brain (coming in 2021 courtesy of COVID and 5G perhaps?! joke everyone) you are reliant on devices converting them to analogue to enjoy them with your senses, and the devices that perform such conversion often care about more than just the bit of data. They often care about exactly when that bit of data arrives relative to other bits; the result of this is that you can have two signals which each have zero data loss, but produce quite different results through a given DA converter. The very best receiver equipment is able to attenuate the effects of this jitter to the point where it isn't of relevance for the conversion, though that comes at cost and complexity and may not be possible in some particular piece of equipment you particularly like.

In audio conversion the effects of this are very well known and quite easily measured. You can read about some of the techniques here:
A Case of the Jitters. Full disclosure, in my day job I do some work for Prism Sound, whose engineer Julian Dunn (well before my time there) developed the J-test signal commonly used in audio testing for jitter rejection capabilities. These are peer-reviewed techniques employed throughout the industry.

It is reasonable to assume similar issues may exist in video, where pixel data has to be converted to photons ultimately. Though unfortunately I'm unaware of attempts to quantify such effects. While audio presents a relatively "simply" attacked problem for measurement (still a life's work for many) - you can measure pretty much the analogue waveform you will ultimately experience in your ear. There isn't a standard interface to the panels that has a good correlation to how we see. So you're a few more steps removed from the physical experience in what you can measure. Such a thing doesn't exist in the commercial world in this form, and would be a work of academic interest I think. As an alternative approach, on an HDMI signal, using a sufficiently high bandwidth measurement setup you could perhaps, for instance, measure the differences resulting in an HDMI output from various changes in the signal chain (including PSUs); but you'd have to infer that those differences caused visible issues.

You might be able to come up with some whizz-bang way of detecting and quantifying these matters (FFT analysis of high speed, high res images come to mind, for example). Or perhaps if you believe you can see the differences, you can submit yourself to A-B-X testing organised by someone else (most golden ears and eyes dislike :) ), prove your ability to discern the differences between gear at at a statistically significant level, and then become a "golden eyes".

Note that the above all assumes you have signals that are good enough that they are perfectly recovered in the digital sense. There are some other approaches that can be interesting - such as using a setup that "barely" works (or even better, "only just doesn't work"), and then measuring whether or not changes made improve or worsen performance. This can be a lowtech way of inferring relative robustness differences in receivers (or quality of transmitters). And if your system is already bad enough that you experience frequent breaks in sync that are frequent enough for you to be able to enumerate and establish a rate of failure, then potentially you might have a system where you can infer benefit of some change of equipment just by virtue of it breaking less...
 

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The pattern is the Reference black level PLUGE pattern. The picture (as I see it here) indicates the Optical black in the projector is correct. In other words it looks the way it should.

Load this pattern with the Adjustable mode. If it looks the same (it will if the Radiance Pro Black = 0) then the digital black is also correct.
How is this pattern actually used to set the Brightness level on the display? Of the bars running vertically in the centre, are we to adjust Brightness so that we can no longer see the left most bar?

How are you determining that it looks the way it should?

And similarly, is the 100 IRE window pattern in the reference menu on the Lumagen what we should be using to measure peak white (with meter)?

Or is it better to use a pattern disk fed from a player source running through the Lumagen?
 

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aka jfinnie
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How is this pattern actually used to set the Brightness level on the display? Of the bars running vertically in the centre, are we to adjust Brightness so that we can no longer see the left most bar?

How are you determining that it looks the way it should?

And similarly, is the 100 IRE window pattern in the reference menu on the Lumagen what we should be using to measure peak white (with meter)?

Or is it better to use a pattern disk fed from a player source running through the Lumagen?
There is some description of the use of these patterns here:
And

Both docs are in the tech tips section of the website.
 

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Unfortunately this is an overly simplistic, commonly held view of the world, that digital means no difference in outcome is possible if only you can clock back in the same bits, for you cannot enjoy those digital signals as-is. This generally hold true in computer science where things stay digital, and the education of the masses in such technology has led them to a welcome yet incomplete understand of "Digital". Until you get a digital interface card for your brain (coming in 2021 courtesy of COVID and 5G perhaps?! joke everyone) you are reliant on devices converting them to analogue to enjoy them with your senses, and the devices that perform such conversion often care about more than just the bit of data. They often care about exactly when that bit of data arrives relative to other bits; the result of this is that you can have two signals which each have zero data loss, but produce quite different results through a given DA converter. The very best receiver equipment is able to attenuate the effects of this jitter to the point where it isn't of relevance for the conversion, though that comes at cost and complexity and may not be possible in some particular piece of equipment you particularly like.

In audio conversion the effects of this are very well known and quite easily measured. You can read about some of the techniques here:
A Case of the Jitters. Full disclosure, in my day job I do some work for Prism Sound, whose engineer Julian Dunn (well before my time there) developed the J-test signal commonly used in audio testing for jitter rejection capabilities. These are peer-reviewed techniques employed throughout the industry.

It is reasonable to assume similar issues may exist in video, where pixel data has to be converted to photons ultimately. Though unfortunately I'm unaware of attempts to quantify such effects. While audio presents a relatively "simply" attacked problem for measurement (still a life's work for many) - you can measure pretty much the analogue waveform you will ultimately experience in your ear. There isn't a standard interface to the panels that has a good correlation to how we see. So you're a few more steps removed from the physical experience in what you can measure. Such a thing doesn't exist in the commercial world in this form, and would be a work of academic interest I think. As an alternative approach, on an HDMI signal, using a sufficiently high bandwidth measurement setup you could perhaps, for instance, measure the differences resulting in an HDMI output from various changes in the signal chain (including PSUs); but you'd have to infer that those differences caused visible issues.

You might be able to come up with some whizz-bang way of detecting and quantifying these matters (FFT analysis of high speed, high res images come to mind, for example). Or perhaps if you believe you can see the differences, you can submit yourself to A-B-X testing organised by someone else (most golden ears and eyes dislike :) ), prove your ability to discern the differences between gear at at a statistically significant level, and then become a "golden eyes".

Note that the above all assumes you have signals that are good enough that they are perfectly recovered in the digital sense. There are some other approaches that can be interesting - such as using a setup that "barely" works (or even better, "only just doesn't work"), and then measuring whether or not changes made improve or worsen performance. This can be a lowtech way of inferring relative robustness differences in receivers (or quality of transmitters). And if your system is already bad enough that you experience frequent breaks in sync that are frequent enough for you to be able to enumerate and establish a rate of failure, then potentially you might have a system where you can infer benefit of some change of equipment just by virtue of it breaking less...
I guess I fall into that overly simplistic computer science category and really know nothing about this compared to you :) Okay, so it comes down to differences and handling the signal in the receiving end, ie. DA converters and displays. So if we use a test device that can not see any differences, some displays/da converters can still get different results. Interesting, I get it now! Sound's like a nice study for someone to figure out what kind of visible issues there might be.
 

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aka jfinnie
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I guess I fall into that overly simplistic computer science category and really know nothing about this compared to you :) Okay, so it comes down to differences and handling the signal in the receiving end, ie. DA converters and displays. So if we use a test device that can not see any differences, some displays/da converters can still get different results. Interesting, I get it now! Sound's like a nice study for someone to figure out what kind of visible issues there might be.
There's another good overview description of the issues ref: audio on it here:
You can see that in pro audio jitter is considered a significant problem, as the jitter at the recording stage is baked-into the digital recording forever.

This of course is all just relative to matters of jitter and how it impacts audio. Whether or not a change in PSU in an HDMI video processor can result in differences in recovered clock jitter that are measurable in a piece of connected audio equipment - well, you'd have to measure that, i'm never convinced until it's measured (or ABX'd). I'm certainly not saying this is proven - I'm unaware that anyone has hooked up a Linear PSU to a Lumagen, played something like J-test through it and shown measureable reduction in effects on a connected piece of audio equipment.

Issues may not of course be limited to the effects of jitter - it's possible that switching noise from a PSU might couple into the HDMI output, and then might couple into the analogue hardware in an audio processor. Again though, without test and measurement, these are all just "mights". :)

For what it's worth; for video, while I think it almost certainly would be measureable if you looked hard enough (most things are), I'm certainly not altogether sure this would cross the threshold of being visible to the eye.. Would need the ABX testing above to see if you were crossing a threshold into visibility.

Unfortunately the testing seldom happens :)
 

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There is some description of the use of these patterns here:
And

Both docs are in the tech tips section of the website.
Thanks, much appreciated.

Another question/issue:
I have a StudioTek 130 G4 Wallscreen 2.5 in 2.41:1 aspect, an NX9 and a DCR.
My dealer set it up to merge 2.35 and 2.4 aspects together.

When I play 2.4 movies (The Hobbit Trilogy, The Matrix, etc.), my sides are aligned tight with the side bezels (can't zoom tighter). but I have relatively quite a bit of overscan on the top/bottom.
I understand this to be normal, but I wonder if there is any way to correct it?

I've tried re-tweaking my DCR's tilt, but it doesn't seem to shorten the height of the image.
I only notice it when I game, as I can't read some of the game's graphics along the bottom due to the overscan.
 

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aka jfinnie
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I have a StudioTek 130 G4 Wallscreen 2.5 in 2.41:1 aspect, an NX9 and a DCR.
My dealer set it up to merge 2.35 and 2.4 aspects together.
Sorry, I don't have any DCR experience, but there are other owners here, maybe they can help.
 

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what? been over a month since a FW update? slackers lmao im kidding of course. just noticed they were monthly since like august.

Loving mine!
 

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Thanks, much appreciated.

Another question/issue:
I have a StudioTek 130 G4 Wallscreen 2.5 in 2.41:1 aspect, an NX9 and a DCR.
My dealer set it up to merge 2.35 and 2.4 aspects together.

When I play 2.4 movies (The Hobbit Trilogy, The Matrix, etc.), my sides are aligned tight with the side bezels (can't zoom tighter). but I have relatively quite a bit of overscan on the top/bottom.
I understand this to be normal, but I wonder if there is any way to correct it?

I've tried re-tweaking my DCR's tilt, but it doesn't seem to shorten the height of the image.
I only notice it when I game, as I can't read some of the game's graphics along the bottom due to the overscan.
Set it up so that the top has more overscan and the bottom has less.
 

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Yeah, Jim and I tried that over the phone one time and it was a no-go. I had tons of handshake issues going from my source devices, to the Denon, and then a single output into the Lumagen. The video would lock on sometimes, other times it wouldn't unless I turned various devices off and on. The Denon was acting super flaky. If it hadn't, I probably would've stuck with that configuration.
I initially had it setup like this with my Denon 8500, and it wasn’t great. In addition to handshake issues, the picture quality noticeably improved when the Lumagen was connected directly to the projector (and all processing was disabled on the Denon 8500).
 
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