Europe ... LOL, N.America is the capital of big pharma .....
In some ways that may be true, but I believe there has been more success to date in having naturopathic and homeopathic products banned there than in North America. Action on the side of "big pharma" is quietly ongoing, though, with the aim of replacing natural medicinal compounds with their chemical, patentable, equivalents. We can only hope they are equivalents because, with the money and incentives behind this (aided by apathy in the public at large) they may well win this battle.
Well done, a.wayne, we're finally talking the same language ... yes, reproduction with decent intensity, the end goal - as you note, YouTube is capable of capturing some of the qualities that matter in audio ...
The half brother of this unit, driven by the top of the line MBL electronics is what got me going again in audio, from a high end show 10 years ago; they had a rep direct from Germany nurse-maiding it at the time. But even then, it started showing problems towards the end of the track - I thought, good progress has been made, but still the problems, the gremlins lie in wait, ready to do their damage ... my enthusiasm for the game was rekindled ...
I honestly couldn't say, Russ. Some titles have appeared in book shops regarding traditional medicine, mostly herbal, but I cannot judge how good or domprehensive they are.
Regarding "Big Pharma", ask my wife about medicine and drugs and she'll tell that there are in fact only three true medicines:
1, Aspirin, the one and only true miracle drug, one of the few we know all about,
2. Antibiotics, on the decline due to large investments necessary and small profit margins,
3. Traditional herbal medicine.
All the rest is a mixed bag, it cures one thing, but upsets another. Lots of unwanted side effects.
Regarding "Big Pharma", ask my wife about medicine and drugs and she'll tell that there are in fact only three true medicines:
1, Aspirin, the one and only true miracle drug, one of the few we know all about,
2. Antibiotics, on the decline due to large investments necessary and small profit margins,
3. Traditional herbal medicine.
All the rest is a mixed bag, it cures one thing, but upsets another. Lots of unwanted side effects.
amp 101 questions continue.........
consider a conventional solid state class AB amplifier driving a conventional passive speaker. If I understand correctly at low power levels the amp operates in class A, at higher levels class B, what is the threshold at which class B begins? Is it when the peak signal swing between the positive and negative power device bases equals 2 x 0.6V, or at some other voltage threshold?
consider a conventional solid state class AB amplifier driving a conventional passive speaker. If I understand correctly at low power levels the amp operates in class A, at higher levels class B, what is the threshold at which class B begins? Is it when the peak signal swing between the positive and negative power device bases equals 2 x 0.6V, or at some other voltage threshold?
It is only about current, not voltage. When the current in one of the devices reaches 0, then it is class B. On standard emitter follower output stage with emitter resistors this happens at a current equal to 2x the idle bias current.
The trouble with GMO is not the idea in itself, but the fact that it needs exceptionally long trial runs for testing. WE are playing with almost atmoic level here, it takes decades to test it, and Monsanto dosn't have decades to wait.
Clinical tests of an aspirin last for 3-5 years, now think of the genetic level and the almost infinite number of possibilities to go wrong somewhere. And if something does go wrong and something gets into our genes, how do we correct that?
Also, it's not just the food, it's also our typical feeding habits. My grandma taught me that the best way to eat was to use just about everything in a mix, say for lunch, soup, main course, salada along with the main course, perhaps something sweet and some fruit. Well, it seems she got the general idea right, but was all wrong about the sequence, because it appears our stomach can't hande very different types of food, like meat and fruit, all at once, at least not efficiently so. Better to eat meat for lunch, and eat supper in form of fruit.
BTW, we are in transition on that too, until recently, we were used to having a proper breakfast, a proper lunch anda proper dinner. The modern way is to have a strong breakfast, relatively light lunch and a good dinner, as mandated by the 9-17 hours work day. Until a few years ago, people locally used to work from 6-8 in the morning (factories from 6, offices from 8) and have changed this just 7 or 8 years ago. This is a short period for something that was customary for the last 200 years or so.
Besides, Big Pharma has an answer to that. You lack calcium - take a pill. You lack manganese - take a pill, etc. There's a pill for every deficiency you can name.
Speaking of miracle drugs , mix bags and unwanted side effects , best to have at least 25watts of class-a bias at 8 ohms on that monsta of yours , 40 would be preferable...
So play with it. But let me warn you, in my experience, once you get to about 130 mA per output device, nothing really happens any more, you need to hog it all the way to all pure class A then.
Also, from experience, on a H/K 680 integrated amp, the bias is set to around 80 mA per device (2 output pairs per channel). AS you raise the bias level in 10 mA increments, what happens is that the sound does get a little sweeter and more sort of fluid, but also seems to lose some focus, and THD increases (by not much, but it does increase).
Every amp seems to have a "sweet spot", so to say, whwre all this comes together just right; go below or above, and the sound changes, not always for the better.
When the current in one device drops to an unchanging value, it is no longer controlling the output. It is then NOT in ClassA.
The current in the not controlling device does not have to drop to zero for the amp to transition to ClassAB (for Push Pull) or to clip (for SE).
amp 101 the questions continue.......
take a simple DC transistor amplifier, two resistors and an NPN, single supply, Rc in series with the collector and Re in series with the emitter. I think the gain is the ratio of Rc to Re, but, when I do a thought experiment and make Rc = 0 then I have an emitter follower whose gain we know is slightly less than 1, so the Rc to Re ratio doesn't work in this case. What other gain equation should I be using instead (simple answers only please )
take a simple DC transistor amplifier, two resistors and an NPN, single supply, Rc in series with the collector and Re in series with the emitter. I think the gain is the ratio of Rc to Re, but, when I do a thought experiment and make Rc = 0 then I have an emitter follower whose gain we know is slightly less than 1, so the Rc to Re ratio doesn't work in this case. What other gain equation should I be using instead (simple answers only please
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If you're not aware of this site, lots of good info here - and something that may help with those ol' basics ... ESP Amplifier Basics - How Audio Amps Work ...
Yes ! (I was over-simplifying). Maybe class A should be described as "both output transistors always control the output"...
Like non-switching class A where one of the transistors becomes a current source when inactive, it gets rid of crossover glitches, but not of gm-doubling... it isn't class B or even AB (inactive transistor isn't off), neither really class A (one or both transistors control the output depending on current)...
I would not say you were oversimplifying.
There are many out there that want to claim ClassA abilities for output stages that have one device not actually switching OFF.
The redundant devices do not take part in the "no crossover region", it's as if they were not there.
The "clever" stage still has crossover distortion during the "handover" from a two device control to a one device control and back again.
I have bumped into several papers describing single ended stages where the bias is adjusted dynamically. These too fall into this category of claiming ClassA operation when one ignores the "errors" of the sliding bias.
There are many out there that want to claim ClassA abilities for output stages that have one device not actually switching OFF.
The redundant devices do not take part in the "no crossover region", it's as if they were not there.
The "clever" stage still has crossover distortion during the "handover" from a two device control to a one device control and back again.
I have bumped into several papers describing single ended stages where the bias is adjusted dynamically. These too fall into this category of claiming ClassA operation when one ignores the "errors" of the sliding bias.
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