I just installed my PS Audio HDMI-10 on my Sony tv and the colors are significantly more vibrant. Very worthwhile.
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Well, that’s sort if the point of this thread. The changes are clear to anyone that’s visited, so any analysis that says they aren’t there is clearly making bad assumptions.
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Mine too. And that’s on a brand new Sony A90J. Even the installer was surprised. We tried with and without multiple times. The same thing with the Shield TV Pro. It was obvious. We were using a Star Trek blu-ray running on our Oppo.
Lets look at this. The video is not PCM in consumer HDMI ever. As I described above it is scrambled on two levels. One for data recovery reasons and the other for copy prevention.
To slightly change a color or sharpen risetimes I must change the digital value. In PCM changing the lower bits would make slight changes in the brightness. But as the signal is scrambled just one bit flip will destroy the data for that pixel. It will decrypt to a totally different value. Now on the transmission side up to your home, bits flip all the time due to errors. But those protocols have error correction built in. They can recover for bit errors. HDMI has no such error correction.
So how is an HDMI cable going to precisely alter not one, but three scrambled video paths, RGB, to make subtle changes in brightness or definition? In color correction we have enterprise servers with up to eight high end GPU cards to make even subtle creative color corrections. But you think this can be done with just a more expensive HDMI cable?
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My girlfriend and I are going to one of my favorite restaurants tonight.
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I suppose this is going to head down the path of i2S soon and how we hear a difference with different cabling.
Do you get the same thing or is the menu good from top to bottom?
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I was wondering, when you peer review a scientific paper, do you have to take your own deckchair? It’s all the crazy words in this science stuff, like thermistor, which had me thinking lobsters. It does my head in.
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I’ve been all over the menu and I like most of it.
We’re doing meatless March and they have great veggie dishes.
And their “house Cab” is quite nice.
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I love places like that. You know, a place where if you read the ingredients list, you still can’t imagine what it’s going to taste like.
Wait…an analogy.
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Not JUST the ingredients, but the amounts, by weight.
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We’re off!
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Now you have me thinking about eggplant.
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I have several scales, mostly for use in cooking and making coffee. I’ll have to get one for my car. I’ll put it in the glove compartment next to the measuring tape, cork screw, pocket knife, and bag of quarters.
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Weight doesn’t matter if you use a fork, since it punctures foods and they leak. Much better to use the digital system—fingers.
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First picture only P20 plugged into a10 gauge dedicated 20 amp outlet by AQ Dragon HC powering plasma TV. Note square pixels
Second picture
Plasma TV plugged into another 10 gauge 20 amp outlet on its own circuit breaker.
You can see it plugged into wall under amp cables
Look at NBC peacock waves in white field clearly noise.
Any questions?
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The camera clearly has moved position between the two pictures. That is aliasing between the camera pixel grid and the TV pixel grid.
Put the camera on a tripod, adjust to kill the aliasing, then re-take the two pictures without disturbing the camera position.
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So, I registered here to comment as an audiophile who learned of this back and forth on ASR. I’ve read all three complete threads, including all the replies here and the one point that I haven’t read or seen really vetted out in my opinion is the most important aspect of the entire discussion:
The P12 regenerators end purpose for being used in an audiophile setup is to increase the fidelity of your sound system by supplying regulated power to your system.
There are a few main “definitive” ways to test whether or not your audio system would benefit from this extra power regulation step:
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To measure the output from your system before and after inserting the P12 into your audio chain and then using existing audio research on audibility thresholds (peer reviewed data from places like AES) to conclude if any changes are audible or potentially audible.
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To setup a controlled listening experiment where the audio chain can be quickly switched between being powered from the mains or through the P12. The SPL of the speakers under test need to be matched with a voltmeter to account for any level differences in each of the two pathways. The test subject should not be aware of which source power is being supplied from. The assistant changes which source is playing and the test subject would listen and identify which source they believe is playing. The test would be repeated a statistically significant amount of times to determine within what probability the listener could correctly identify the sources above the threshold of a random guess. This would be an A/B single blind test. To further rule out bias, the person switching the systems could also be unaware of which is playing when performing the switching. This would prevent any accidental tells from the assistant as to which source was chosen. That would be an A/B double blind test.
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A null test could be setup where the level matched inputs to the speakers were compared on an oscilloscope with the polarity of one signal reversed. The resulting signal could also be routed to a speaker for audibility testing. If the signals are audibly identical, by adjusting the scope a null position could be found where there is silence when the signals align due to cancellation resulting from opposite polarities. If one signal is different, there will be no null position so when aligned on the scope the output signal and resulting sound from the speaker has to be whatever difference in sound is present between the two signals, for whatever reason. Null tests are commonly used in scientific experiments to determine if there is a difference between two inputs regardless of the cause, the test just identifies if a difference exists. Hooking the output up to a speaker allows the tester to use his own ears to “listen” to any difference, so by definition in this case would determine audibility.
ASR chose method 1. The testing performed is shown in the measurements taken on that forum. What was presented showed that a Topping A90 (a headphone amplifier with demonstrably measured low noise and distortion) output did not significantly change when powered from the available mains versus with the P12. This is an expected result from an electrical engineering perspective because the Topping A90, like many amplifiers designed for low noise and distortion, already has effective power filtering built into the amplifier. Varying quality of A/C power in the US was clearly a design criteria that was solved in the the circuit design and testing stage by the company. This is a normal expectation to have for audio amplifiers for sale from established companies. Amplifiers that are poor at this can be measured to show a lesser ability to filter mains noise. So from the measurements at ASR and the established audio threshold science available for noise and distortion it is fair to say that the P12 does not audibly change the sound in the system tested. Is it possible that an amplifier with poor power filtering attached to extremely poor mains power could benefit from the P12? It would be interesting to see such a setup presented and measured. A call for PS Audio to identify and demonstrate this case was presented.
If you don’t believe that the measurements tell the whole story then one of the other two methods is necessary to demonstrate that a difference, no matter the reason, exists. This is why it is common to see controlled listening tests discussed when there is a disagreement on audibility of any type of change to a system. In this case the onus is on the person making the claim of audibility when it goes against what the currently understood measurements and audio science tell us. Setting up a controlled listening test takes a little bit of effort, but it is not monumental. Any owners of the P12 should be encouraged to make an attempt. Current data on controlled listening tests which have been peer reviewed have not shown the modern understanding of audibility thresholds to be incorrect. But anyone should be open to the idea that there could be some difference that is caused by an effect that has not been accounted for. This is why controlled testing is an important aspect in audio. Bias plays a huge factor in human perception and has to be ruled out in order to demonstrate a reliable change has occurred. When measurements show that an audible change isn’t present anecdotal stories supporting or denying the change are generally considered worthless in the absence of controlled listening tests.
Setting up a null test for this scenario would require some custom equipment but would be interesting. Some people don’t understand the premise of a null test and wouldn’t accept the results regardless of the outcome. This can be seen with some of the responses to Ethan Winer’s null testing of audiophile cables:
My point is that a lot of discussion has been focused on whether or not the P12 meets it’s posted specifications for regeneration or the impedance affects on maximum power from it’s various outputs. But the real question is, does the P12’s regulated power when it’s functioning as intended actually make an audible difference to the output of your system?
From the data I have seen presented so far, with the caveats of average to below average mains power and utilizing an established audio brand amplifier which includes normal power filtering, the answer is likely not.
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So the pixelization difference washed out the colors too. Fools my eyes from across the room. Amazing the ends you will go to.
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Way to go Vmax!!!..Thank you for showing the results of real science…
Might like to post pics of the screen from your regenerator
showing thd % in and regenerated power with the much lower thd.
There is no rebutting that
Best wishes