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Old 12th August 2012, 08:40 PM   #26071
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Quote:
Originally Posted by RNMarsh View Post
We arent interested in fooling imagination .. we are using test instruments here in new and valid ways to learn and get other views of the issues and see where That leads.
So, it is your business to learn how to measure my gear that is designed to fool imagination as if sounds are real...
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Old 12th August 2012, 08:46 PM   #26072
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Waveb -- did you get the solar (UV) film on the sunny-side windows yet? makes a big difference too.
No, I recently replaced huge industry-grade skylight. Don't ask how I managed to find the replacement... What happened, I put a film on it, the film stuck, then oak pollen made it dirty, then one it's layer cracked... Now I am making remote controlled mirror blinds for it, from bronze-looking aluminium kickplates.
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Old 12th August 2012, 09:18 PM   #26073
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This "Beginning steps" were taken many times, but the problem is, people who are afraid of being "non-objective" always ignore them, because it is hard to prove which weighting is better. However it does not mean that absence of weighting is better, but it is "simpler" and more "scientific".
There's established research about masking of one tone by another. The masking is related to the distance between the 'carrier' and the tone being masked (or not), and of course the relative levels. A 2nd harmonic is relatively easily masked by a fundamental because it is close (only an octave). So with a pure 2nd, it cannot be heard when the level is, say below 1% of the fundamental. But, say, the 10th is not masked so easily because of the large frequency separation, so it can still be heard even if it is only 0.1% (I'm just making up the numbers for the narrative, the definite numbers will be in the article).

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Old 12th August 2012, 09:33 PM   #26074
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Originally Posted by Wavebourn View Post
No, I recently replaced huge industry-grade skylight. Don't ask how I managed to find the replacement... What happened, I put a film on it, the film stuck, then oak pollen made it dirty, then one it's layer cracked... Now I am making remote controlled mirror blinds for it, from bronze-looking aluminium kickplates.
DIY has draw backs.... namely experience. The right type of film for outdoor windows is applied to the INside of the glass. Cheaper than miror remote controlled blinds, too. lasts forever.

Without UV blocked BEfore the metal blinds -- just heats up the metal blinds and then both the blinds and the hot glass radiate the heat into the room.
You can also get UV film of different tint darkness or even mirrored .... great for those bathrooms with glass all around them.... on second thought ....

Last edited by RNMarsh; 12th August 2012 at 09:51 PM. Reason: experience helps -
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Old 12th August 2012, 10:27 PM   #26075
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...on second thought, I will be able to close blinds when watching a move, and open when I want it to be light, regulating dispersion according to time of day. UV rays are good; we need UV rays particularly to produce vitamin D that is vital for our body. Also we need sun spectrum because LED lights fooling imagination as if the light is white actually disrupt feedbacks of our natural self-regulating organisms.
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Old 12th August 2012, 10:34 PM   #26076
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Originally Posted by janneman View Post
There's established research about masking of one tone by another. The masking is related to the distance between the 'carrier' and the tone being masked (or not), and of course the relative levels. A 2nd harmonic is relatively easily masked by a fundamental because it is close (only an octave). So with a pure 2nd, it cannot be heard when the level is, say below 1% of the fundamental. But, say, the 10th is not masked so easily because of the large frequency separation, so it can still be heard even if it is only 0.1% (I'm just making up the numbers for the narrative, the definite numbers will be in the article).
If you publications Johannes convince at least Stereophile magazine to accept more realistic measurements you may call it "mission accomplished". Bravo!
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Old 12th August 2012, 10:51 PM   #26077
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To each his own.... [never mind what it did to his relationship and property values.]
Amazing how shallow our culture can be, persuing your neighbors manicured lawn. My neighbor once mowed my lawn and sent me a bill, it went right in the trash (my wife could care less either).
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Old 12th August 2012, 11:04 PM   #26078
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Quote:
Originally Posted by janneman View Post
There's established research about masking of one tone by another. The masking is related to the distance between the 'carrier' and the tone being masked (or not), and of course the relative levels. A 2nd harmonic is relatively easily masked by a fundamental because it is close (only an octave). So with a pure 2nd, it cannot be heard when the level is, say below 1% of the fundamental. But, say, the 10th is not masked so easily because of the large frequency separation, so it can still be heard even if it is only 0.1% (I'm just making up the numbers for the narrative, the definite numbers will be in the article).

jan
In Stereophile I've seen some amps with no feedback and high distortion and lots of harmonics that decrease in amplitude with frequency. They often get great reviews and recently a reviewer called one the best amp he's ever heard. So, perhaps each of the harmonics are masking the higher one? Or perhaps it's just a matter of getting the overtones of the amp to sound non-offensive. Or both.

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Old 12th August 2012, 11:08 PM   #26079
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It seems that no matter what we do to attempt to get a better 'measurement' of audio electronics is 'blocked'. Some think that all amps and preamps are essentially the same, anyway, so why bother? Others think that THEIR hi fi designs are among the best in the world, yet nobody outside their family circle has ever heard them.
Still others don't want to invest in the highest quality, due to not having enough cash free, and they mostly use MP3. CD maybe, for special occasions.
This business of weighting harmonic distortion goes back at least 75 years.
The 'Radiotron Designer's Handbook' is a good source for early work.
There, they wanted to put a multiplier on every harmonic and then divide by 2 to get the weighting number for each harmonic, so: 2nd=1, 3rd=3/2, etc.
Later research showed through listening tests (whatever they did) showed that a steeper weighting factor was better. A good approximation is n(squared)/4. So: 2nd=1, 3rd=9/4, 5th=25/4 and 7th=49/4 or more than 12 times 2'nd.
Amazingly, the Gedlee weighting is almost the same as n(squared)/4 with a few exceptions. Seems that they are on the right track.
So what is the beef? Why not adopt a weighting filter?
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Old 12th August 2012, 11:12 PM   #26080
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So, perhaps each of the harmonics are masking the higher one? Or perhaps it's just a matter of getting the overtones of the amp to sound non-offensive. Or both.
Or perhaps the distortion is low enough that it doesn't matter? And maybe Gedlee knows what they're doing?
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