And who are you in this picture the decapitator or the to be beheaded.
I feel sorry for both.
Hans
I will be charitable and hope you wrote that in jest, as what you quoted wasn't entirely wrong (given the work I do), but also mostly written in humor.
Otherwise it comes across incredibly insulting.
Have fun on your vacation, Richard. I rarely listen to my vinyl, unless I want to hear the best fidelity (subjective, not measured) that I have available to me.
I guess that the dac mod created a more complete shield from digital interaction on the board. Makes sense to me!
I guess that the dac mod created a more complete shield from digital interaction on the board. Makes sense to me!
I apologize if you had took-it first degree, I was, indeed, hoping you were joking.
Only one thing was serious, it was about the percentages. And I was not putting-you in any category: How could-I do, while I don't know you ?
Just I dislike emoticons: "humour inside".
No insult intended.
Scott,
Still thinking of your Cymbal image where you subtracted the before/after filtering time domain envelopes.
There was this unexpected lower frequency in this delta image and at the same time, the higher frequencies above 22050 that were part of the unfiltered version were missing in the delta version.
Since the filtered version was at fs 44100, could it be that the lower frequency below Gibbs in the delta plot was caused by aliasing the frequencies above Gibbs?
If not, what happened to these frequencies above 22050 ?
Hans
Still thinking of your Cymbal image where you subtracted the before/after filtering time domain envelopes.
There was this unexpected lower frequency in this delta image and at the same time, the higher frequencies above 22050 that were part of the unfiltered version were missing in the delta version.
Since the filtered version was at fs 44100, could it be that the lower frequency below Gibbs in the delta plot was caused by aliasing the frequencies above Gibbs?
If not, what happened to these frequencies above 22050 ?
Hans
Yes, I believe that was the idea behind the mods. Keeping an open mind ... .
maybe something like this --
EMI / RFI Shielding | Conformal Coating
US20010033478A1 - EMI and RFI shielding for printed circuit boards
- Google Patents
It is black color so graphite over the digital area. ??
Plus additional more conventional shielding techniques applied to the nearby analog area/parts.
-Richard
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Of course it does, but PMA said the result would never be accepted. Not consistent with prior published research, apparently.
I'm a little busy the next few days, be patient. I have gotten some feedback that this is a useful path of research.
What does the prior pub research say? It used to be 40KHz caused audible phase issues. Thus, the reason behind my comment on BW being at least 40KHz. But, that was before things got as refined as they are now.
[having visa issues and have to correct them... then outta here]
THx-RNMarsh
I thought you didn't believe in visas, just sneak in. Try that in North Korea or Myanmar we would probably lose you.
I unfortunately missed the posts you are referring to, but I am convinced Pavel has very good and trained hearing. He has demonstrated so on multiple occasions. There is a small group of people that really stand out in this respect, no doubt.
The point, Mark, is that these people can discern real, measurable differences. Make the difference larger and the percentage of people that can discriminate will grow, so without knowing the stimulus, it is nonsense to ascribe a percentage. Pavel no doubt belongs to a quite small group in this respect.
The 14% relates to people hearing differences that are not really there. Bybees, cable directivity, the brightness of silver wire, coupling caps, there is a long and somewhat commercially interesting list to be compiled. I should perhaps include black gunk on the inside of a DAC. There is no difference to be measured, but still these people hear differences.
Hearing things that are not there are auditory hallucinations, and that group is estimated to be 14%. From all the evidence you have presented, you belong to this latter group.
Bob, brilliant joke!
As to phase shift. All tweeters are low pass filters with dominantly LTI characteristics. Woofers are high pass filters. Therefore, there are always phase shifts at both ends of the frequency spectrum a loudspeaker can produce.
Makes me interested to learn more about Pavel's observation.
As to phase shift. All tweeters are low pass filters with dominantly LTI characteristics. Woofers are high pass filters. Therefore, there are always phase shifts at both ends of the frequency spectrum a loudspeaker can produce.
Makes me interested to learn more about Pavel's observation.
Don't forget, Markw4 and RNMarsh both listened to it the way described below.
"IOW, there was no procedures taken to match levels within 0.1 db between components under test. As for for visual bias control... Oh, never mind."
RNMarsh: "None what so ever..... we heard the same quality and affects regardless of level."
Hahaha. yeah. You rememberd! Got lucky in Xian, China. After 3 days being shown around, was told who guide really was. Chief of police daughter. She decided we were OK and showed us places she said no weaterner had ever seen or even been those places. had a wonderful time. Myanmar is my next place to visit. I was there in the north with karen people and long neck people tribe with no visa but now... ?? Night time curfew.. shoot to kill.. ask questions later. A major H smuggling route but now pills are big business. N.K.? Never going there.
Coming out of the hills near Burma/Myanmar/Thai border region I wanted to get out fast and asked if we could take river down to valley. In an hour they made us a raft and gave us a guide and away we went. Only crashed into rock once. Dodged water buffalo.
Jungles in the south Myanmar/Thai are too thick to live in so villages are on river Qui. Later, found out this region is the epi-center of the world for malaria. We used a raft again. No roads around there. some importers smuggled Piranha into Thailand and this river has them. Our lunch chicken bones were used as demo the fish are there in abundance.
An airport of sorts now exists in Mandalay so i want to go there while it is still wild and people living as they have for centuries. In northern Laos, we watched how the village people wash them selves in the river. All women and kids still go in naked in groups at end of the day.... women, girls, boys and men. Ate dinner at the dictators home. He was run out but his wife stays there in their home.
Anyway ... sorry. Got carried away. Back to the really important things like audio.
-Richard
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It is important to know the FR and GD of the 100Khz filter. Just knowing 100Khz tells almost nothing. It could very well cause a noticeable GD at 10Khz or even at a lower frequency
So yes, I’m also anxious to know the details of PMA’s test.
Hans
The ear is surprisingly insensitive to GD - see Tomlinson Holman papers for example where this subject was touched on.
You have to have some seriously non-human hearing to discern a 100kHz roll off -assuming 100 kHz was the -3dB point.
If we are happy with 22kHz brick wall filters vs a soft filter in a 24/192 system - ie we cannot tell the difference in normal music material, what does that say about 100 kHz filter where the 20 kHz impact is about 0.3 dB?
I doubt PMA has 20-20 hearing. He’s not a young guy.
Some other explanation is required.
You have to have some seriously non-human hearing to discern a 100kHz roll off -assuming 100 kHz was the -3dB point.
If we are happy with 22kHz brick wall filters vs a soft filter in a 24/192 system - ie we cannot tell the difference in normal music material, what does that say about 100 kHz filter where the 20 kHz impact is about 0.3 dB?
I doubt PMA has 20-20 hearing. He’s not a young guy.
Some other explanation is required.
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