In researching- what in a capacitor could affect the sound quality -- that is the paper I found at LLNL tech library and refered to it later to you and WJ and if IIRC footnoted also in WJ and RM's Audio article... "picking capacitors'
THx-RNMarsh
Very true, credit should go to the SpaceX Engineering team for getting that up (and 2/3 of it down again). You do hear horror stories about working for Musk, but I suspect the core team there are loving it.
Now of course total money burned so far by spaceX is not listed, but NASA has nommed up nearly $8bn and launched nothing on SLS. Part of me hopes that, providing quality and reliability* can be maintained, NASA passes on rocket development and gets more money to spend on what it's really good at.
For example Latest Data From IMAGE Indicates Spacecraft’s Power Functional | NASA lost for 12 years and now found to be apparantly in good working order and ready to do science again. Built NASA tough!
*Yeah I know there is a question mark over Zuma, but no one knows that that is/was anyway. Most secrecy I have known since this Zircon (satellite - Wikipedia) .
But all in all a good time for science and technology!
The feedback mechanisms are there from birth. A lot of them are tested in babies as reflexes*. From just a few months babies will look at something they want then reach for it whilst looking in the opposite direction. It's remarkable the rate at which synaptic pathways are being built to process all the feedback signals.
*Dunno what the biology types currently think, but you could argue the babies reflexes at birth a entirely feedback as they are not processed by the brain at all. Complex stuff but defiantly not open loop 🙂
I barely know any biology, but EVERYTHING about keeping things alive involves feedback loops of sometimes insane levels of complexity.
Biochemical systems within a cell, through ecosystem levels can all be described as feedback. It'd be so ridiculous to not acknowledge its ubiquitousness.
Biochemical systems within a cell, through ecosystem levels can all be described as feedback. It'd be so ridiculous to not acknowledge its ubiquitousness.
Yes, and this is where pesticides and other synthetic chemicals are so dangerous through action of mimicking hormones and altering/disrupting other physiological processes and reaction pathways some of which are key components of sensitive and complex biological feedback systems.
The above applies to plants also and in so doing can alter mineral and other nutrient content.....this is the other side of the value/neccessity of biodynamic/organic produce.
Dan.
A quick survey of commercial PA schematics with servos showed that many of them would cease to function or self destruct with more than .5 to 1V DC on the input. Quite a few use a +-15V op-amp at the same equivalent gain as the PA so at 26dB its .75V DC that rails the op-amp.
Many output offset servoing PA's still have an input coupling cap.
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Most of the most dangerous substances on the planet are all natural. But we can get very political about this very very quick. Organic produce, especially at the commercial farming level, is not without its massive sins and "natural pesticides/fertilizers" that are known to be more toxic than a lot of the synthetic stuff.
I'm not endorsing one or the other, but rather that nothing is sacred. There is not a panacea.
Scott, you are talking about an area that is not your expertise. Of course, somebody might add an input coupling cap for extra protection, but usually we just have the protection circuits fire when too much DC offset is noted.
Scott,
When you have a sin function for v then dv/dt is a cosine function only phase has changed. As an infinitely long piece of music would not be only composed of sin functions the derivative could be sometimes changed not just in phase but also amplitude that would be a source of distortion. Harmonics that were not present in the original signal would be produced. It is the technique applied to time limited music that allows it to be reduced by Fourier's method to just a sum of the sines. In doing so you require much more bandwidth than the original signal. Also demonstrated in practice. You are correct in your limited use of the word linear as music certainly does not graph as a straight line. In engineering a circuit that passes signal with only amplification or attenuation is considered linear. As no real circuit is perfect they are all nonlinear. We can rate this variation by the harmonic and non harmonic distortion produced. But you knew that you just want to argue.
But then we never agree on anything. I do remember when one of your fellow travelers didn't agree with CV = q.
When you have a sin function for v then dv/dt is a cosine function only phase has changed. As an infinitely long piece of music would not be only composed of sin functions the derivative could be sometimes changed not just in phase but also amplitude that would be a source of distortion. Harmonics that were not present in the original signal would be produced. It is the technique applied to time limited music that allows it to be reduced by Fourier's method to just a sum of the sines. In doing so you require much more bandwidth than the original signal. Also demonstrated in practice. You are correct in your limited use of the word linear as music certainly does not graph as a straight line. In engineering a circuit that passes signal with only amplification or attenuation is considered linear. As no real circuit is perfect they are all nonlinear. We can rate this variation by the harmonic and non harmonic distortion produced. But you knew that you just want to argue.
But then we never agree on anything. I do remember when one of your fellow travelers didn't agree with CV = q.
Yes, ONE capacitor not one at every stage as used to be the case in most designs. In most simple audio power amplifiers two are used. One to block input DC and a second to reduce the DC gain to unity. That design or the switching amplifier equivalent is used in virtually all audio amplifiers except the ones designed for the highest quality of reproduction.
I really don't need DC coupling for any of my arena or stadium designs. Recording studios seem to prefer other fussier audio amplifiers.
I paint my walls white at home. It allows the wood floors and oriental rugs to stand out. My office has colored paint and carpet, a different intent, design and need. (Shop has concrete floors and wall color is unimportant other than white allows the best illumination for safety.)
Or as the saying goes "Whatever floats your boat.)
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I reserve the right to limit the use of concepts that are just plain wrong. You should read the excellent reference on windowing that I posted. The relationship between time record length and frequency resolution is as fundamental as Heisenberg's, there are no new frequencies created by the Fourier integral.
You statement is correct and mis-applied. There are no new frequencies. They were always there.
The best example is in a piece of music that starts off almost lost in the noise floor rises to a crescendo and then fades back into the noise floor. That volume change would be represented by a very low frequency in the full length sample.
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Well, that's not quite the case. Here is a list of the most dangerous substances on the planet:
List of extremely hazardous substances - Wikipedia
Pay particular attention to Putin's (you know, Trump's good buddy) favourite murder weapon - Polonium 210:
Isotopes of polonium - Wikipedia
For all intents, Polonium 210 must be manufactured by humans, though it COULD be found in nature, though you would need to look REALLY hard.
210Po is extremely toxic, with one microgram being enough to kill the average adult (250,000 times more toxic than hydrogen cyanide by weight)
Sure, there are plenty of deadly elements and compounds found in nature, but for the really nasty stuff, look to what humans have developed.
Even though it's only in small amounts it's naturally occuring, that's how Curie found it!
Botox is also pretty nasty, natural and people pay to be injected with it. Bonkers!
Botox is also pretty nasty, natural and people pay to be injected with it. Bonkers!
To the extent capacitor DA can be accurately modeled as an RC ladder network it is linear. If there is deviation from a linear model such as in the case of a voltage coefficient, then C is nonlinear. I don't think we need to know more than that at this point, do we?
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No. Scott's statement is correct and your's misapplied. You must integrate to infinity and your function must continue until then if you want a discrete frequency. It would have to be silent-loud-silent-loud until the cows come home.
A single silent-loud-silent would produce a spectrum much like a Dirac pulse, i.e. very flat and the energy of the signal would be smeared from DC to infinity, leaving everywhere about nothing.
The purpose of the window function is to define a fake cycle that is treated as if it was repeated forever. It makes "the ends meet" so the transition from one cycle into the next is smooth. Therefore the window functions all have large numbers in the middle of the window and zeros at the beginning and the end. Depending on the curvature you get differently wrong answers from the Fourier transform: spilling to neighbor bins, side lobes or whatever. That's the price you pay for faking infinity.
To repeat it: a single silent-loud-silent has no defined frequency, let alone a low one. At best, it produces an infinitely low signal at all frequencies between DC and daylight.
(And apart of that, the silent-loud-silent, when multiplied with the music, would AM-modulate it, also leaving no low frequency but very close sidebands on whatever frequencies the music has.)
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yes, I said that they did. But not all. But not placed there to add clarity to the sound. Added to protect the amp. However, if we are still interested in talking about SOTA preamps and PA, neither will use coupling caps and do as JC said... provide protection circuit in event of failure rather than mess with the sound. A 'high-end' ss preamp and PA would use servo on preamp out and on PA out.
THx-RNMarsh
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Funny you should note that you go on and on about an element in pure form. What could be more natural than that?
Now on one side, apologies on the superlative; on the other side, congrats on missing the point entirely. Both human and nature have invented all kinds of stuff that will kill you right quick. Ironically, there are several compounds on that wiki link you provided that humans actually produce. What's the saying? The dose makes the poison.
Somebody tried to figure out how to make a condenser mic preamp without using electrolytic caps or transformers to isolate phantom power from the amp input. The idea was to use servoing. Don't know what became of it. All designs I have seen mostly still use caps, and a few with transformers.
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