The original article talked about laying out your design with a microprocessor. Several things should be noted:
First, don't roll your own PCB with a microcontroller on it unless you know what you're doing. This is an involved process and not for newbies. You will need expensive lab equipment to debug even the simplest problems, and it is best to sidestep the problem if at all possible. Consider instead simply incorporating an arduino / Pi / Beaglebone into the actual product and do it that way instead. If the margins are low enough to make this impractical, and you don't have any experience designing microcontroller systems, then I would humbly suggest you are out of your depth, and the profit margins are probably too low for you to make money selling your product.
Yeah, just about none of that is true.
Due to recent accusations of online sexual harassment against Prof. Lewin (who retired from MIT in 2008), MIT has decided to remove all lectures and courses (https://newsoffice.mit.edu/2014/lewin-courses-removed-1208).
Link to Original Source
The state of the art in the field is medication. The drugs have changed over time, but drugs have been the first line of treatment for at least 40 years now. I have both experienced myself, and witnessed in others the indescribable suffering and agony that can occur due to drug side-effects, and those that appear due to withdrawal of the drugs after long-term use. Psychiatry would have you believe, I suppose, that the central nervous system is endlessly plastic, and can rapidly adapt and respond to medications being added and removed as one pleases. For the majority, perhaps this is true - but there is a sizable minority who find their mental health deteriorate the longer they are on the medications, and then discover (to their horror) that they cannot discontinue the drug without terrifying mental and physical symptoms, far worse than the original illness. If it should happen to you, psychiatry absolutely _will not_ have your back, or really anything to offer you, as even the drug manufacturers themselves do not know how the medications affect the brain long term.
One might argue that any treatment has risks, but after experiencing what I've experienced, I think people should understand what kind of risk they're really taking. For my part, I do not consider this kind of medication Russian roulette to be a "basic health care service."
There is no "chemical imbalance" other than what the psychiatric drugs create, and the issue of drug dependence and withdrawal is systematically ignored by psychiatry. It has been shown that long-term use of the medications prescribed by psychiatrists can cause significant changes in brain structure and function that may be difficult or impossible to reverse, and that in susceptible populations attempts to discontinue certain medications can lead to withdrawal reactions that far exceed the severity of the original illness, even with slow tapering. For these people, there is virtually no assistance from the psychiatric community available (aside from a few "renegade" practitioners), and certainly none available from the pharmaceutical industry. Nobody really knows exactly how the drugs work, or what's happening when one tries to withdraw and things begin to go wrong. Keep in mind that in all likelihood you will be blamed for the withdrawal symptoms, not the drug, because acknowledging a withdrawal reaction would force the profession to admit that they have no idea what to do in such a situation.
Huh? A simple bandpass filter does the trick. Higher sampling rate, higher frequency filter. You realize that there are radio frequency filters, which are far higher frequencies than sound?
The maximum achievable dynamic range of an ADC is determined by the bit depth of the converter. In practice, this dynamic range is limited by the steepness of the roll-off of the anti-aliasing filter - you can have a 16 bit converter, which implies 16*6 = 96 dB of dynamic range, but if your low pass filter only rolls off 12 dB before you hit the Nyquist frequency, your dynamic range will be limited to 12 dB. The OP is working under the assumption that the "final" sample rate, as indicated by the information on the
The higher your sampling rate, the less aliasing you get. At 44.1 sample rate has only three data points to describe a 15 kHz wave's shape. That's not nearly enough. I'd guess that if you quadrupled the sampling rate (and raised the number of stored bits) you could sample an analog high quality studio-produced audio tape and nobody would be able to tell the difference between the two.
Oh, BTW, the GP was joking.
I don't know why you say that three data points isn't nearly enough, as the whole point of Nyquist's theorem is that it is, if the signal is perfectly bandlimited. If you mean that it's probably not enough to reproduce a 15 kHz wave accurately given the imperfections of most consumer 44.1 kHz ADC or DAC systems, I think I'd agree with that.