I fear you may be confusing two quite different effects: linear amplification and AGC.JonSnell Electronic said:
Not obvious to those who know that the relevant properties (e.g. permittivity) are irrelevant to audio. As has been said, raising cables may introduce more RF interference which some might misinterpret as 'detail' or 'air'.RayCtech said:
Quite amusing to come across this, from the book "Handbook of Electrostatic Processes" ...
Interesting how there are always pecking orders in every area of human endeavour ...
Electrostatics is more likely to be of interest to a manufacturing or chemical engineer who has to handle powders. Unclear what he means by "pure" physicist: if he means not an applied physicist then the lack of interest is to be expected as there appears to be no new fundamental physics to be found in electrostatics - just some applied physics and maybe some surface chemistry. Every area of science goes through periods of popularity and decline; everyone will complain when their own favourite field is out of favour.
Electrostatics has, of course, nothing at all to do with raising cables on wooden blocks.
Electrostatics has, of course, nothing at all to do with raising cables on wooden blocks.
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If you are a believer in that audio needs only 20Hz to 20kHz bandwidth then you have not done any serious listening evaluations.
I use 0.1Hz to 1MHz as a minimum requirement, but normally designs for 0.008Hz to 5MHz bandwidth. Even my speaker drivers are designed to perform from DC and have FS at 8Hz. But they work of course down to DC.
The current setup are DC coupled (non loop feedback) from the MC cartridge or from the DAC.
It is when you remove RF and other kinds of "noise" and interference that you step by step reveals the quality of the source material.
You mentioned 20Hz to 20kHz, I didn't.
When I lived not too far from Droitwich I could not hear the 198kHz transmitter. I take that to mean that my audio equipment need not go up to 1MHz - in fact it definitely should stop somewhere below 198kHz.
When I lived in London I found near-DC changes in air pressure (on tube trains) to be a bit unpleasant so I would prefer to filter those out too.
Your speaker drivers may move down to DC but they don't 'work' down to DC. You may need to review your speaker theory.
I agree that removing RF is worthwhile; it is unfortunate that some 'audiophile' tweaks might increase RF.
When I lived not too far from Droitwich I could not hear the 198kHz transmitter. I take that to mean that my audio equipment need not go up to 1MHz - in fact it definitely should stop somewhere below 198kHz.
When I lived in London I found near-DC changes in air pressure (on tube trains) to be a bit unpleasant so I would prefer to filter those out too.
Your speaker drivers may move down to DC but they don't 'work' down to DC. You may need to review your speaker theory.
I agree that removing RF is worthwhile; it is unfortunate that some 'audiophile' tweaks might increase RF.
I am one of your so-called believers of 20-20k types......and yes I have done some listening tests.....& you know what? I cannot hear the sound of a horizontal oscillator anymore. They used to be such an annoyance for the longest time....I would have any CRTs in the area shut-down whenever I would like to listen solely to the music...........now its gone, beyond my perception.
Designing for 0.1 to 1Mhz?????? well, your integrating RF into your design....that evil RF......noise as you call it. Megahertz range wont even propagate thru any of your system, let alone make it into your loudspeakers.
Saying you design up to 1Mhz for audio systems is just plain silly........Radio systems yes, audio no.
Tell you what, you think 20K tones...all the way up to 1M............I will generate a 40K test tone & you tell me if you can hear it....well do a double blind.....I will even apply 150 Db for ya.........It might give you an itch but you wont hear it.
_____________________________________________________Rick........
Designing for 0.1 to 1Mhz?????? well, your integrating RF into your design....that evil RF......noise as you call it. Megahertz range wont even propagate thru any of your system, let alone make it into your loudspeakers.
Saying you design up to 1Mhz for audio systems is just plain silly........Radio systems yes, audio no.
Tell you what, you think 20K tones...all the way up to 1M............I will generate a 40K test tone & you tell me if you can hear it....well do a double blind.....I will even apply 150 Db for ya.........It might give you an itch but you wont hear it.
_____________________________________________________Rick........
## Fs at 8 Hz. ## Hate to see the size of your ported alignment enclosure!!
& I thought my 1010 Liter was big...trying to get that lowest note on the pipe organ............
_____________________________________________Rick..........
& I thought my 1010 Liter was big...trying to get that lowest note on the pipe organ............
_____________________________________________Rick..........
Over in the IB forums they do things like this. Multi-18 inchers etc. I think they are really investigating elephant mating calls. Me? Well I go stomp my foot three times every day before I get in the car to keep the pink elephants away. I don't want to clean up after them. It must work as I have never seen any.
Lowest organ note is 16.4 Hz. Inaudible, but you can feel it. I HP filter at 24.
I can still hear the flyback, but not painfully like I used to. Testing tweeters, I know I am still good to a bit over 18K.
40K at 150 dB. What a head ache that would cause,(it will) but from the sound but from every dog in 10 miles barking!
Why wide band amps? It has to do with IM, which after all is said and done, is actually HD in frequencies we can here. 50K seems to suffice. Reading the Hypex white papers, they suggest this is not relevant for class D. Snake oil?
AC/DC?????????????
unless all of your listening is DC, what's your point???
music has everything to do with delta, not static processes...
unless all of your listening is DC, what's your point???
music has everything to do with delta, not static processes...
When the signal travels down a PCB (more often than not a double sided PCB) half the signal is traveling through FR4 a mix of epoxy and glass, and half is travelling through air and a small layer of solder resist. Does it really matter at the frequencies we are worried about.
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Relevant in possibly 3 ways: it can change the operating point of circuitry; if the static field is rapidly varying for some reason then there is an AC component; and if the static buildup is constantly discharging then there are very high, RF frequencies involved.unless all of your listening is DC, what's your point???
music has everything to do with delta, not static processes...
I can hear the impact of altering configurations which appear only relevant to electrostatic mechanisms - if the effect is audible, then it needs to be dealt with.
Why electrostatics should be intriguing to at least some people, is that it is yet not understood. Yes, its behaviour is largely under control, but the fundamental why does it occur is still a great mystery ...
And how do you remove the RF, all commercial stuff sold should have been through EMC testing and have some sort of certification for the area it is to be sold, CE for Europe etc. Most DIY designs I have seen that follow audiophile design principles quite often strike me as very good RF receiver's and transmitter's especially when they paly with digital.
One of the things that was presented on an EMC design course for boards was the following (part 1 only you can find the rest, its also an appendix in his book Electro magnetic engineering). If you are serious about eliminating RF, get his book and study it. And we do now live in an RF rich world, so it is a problem.
http://www.hottconsultants.com/pdf_files/dipoles-1.pdf
One of the things that was presented on an EMC design course for boards was the following (part 1 only you can find the rest, its also an appendix in his book Electro magnetic engineering). If you are serious about eliminating RF, get his book and study it. And we do now live in an RF rich world, so it is a problem.
http://www.hottconsultants.com/pdf_files/dipoles-1.pdf
Don't wanna rock your boat much regarding this static thing but surprise surprise one of the first things I was shown was the damage static discharge could do, and then numerous lessons on how to protect against it and stop it building up. Off course if you are boogying to the music in your Polyester trousers, rubbing up against your amp you may have problems😉 (many), also listening to 'H to He, Who Am the Only One' has been known to also cause the same problem.
How do you sleep at night with all this worry😀
Try a Special Brew...
How do you sleep at night with all this worry😀
Try a Special Brew...
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If you like, I could discuss static damage, with specific emphasis on JFet op-amp input leakage, or as Dr. Anderson says, " making a part pregnant, as it will give birth to a failure later on" I actually wrote the book on this at my old company. Look up ANSI 12-20. I hope that is right. The stark reality is that when a unit is in a box, all hooked up and working, it is STILL susceptible to damage. Damage to the input FETS will be far more audible than any of the snake-oil problems.
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