I agree, your results are fantastic.
I even think most people here can understand why what you did works. Quite possibly they don't even need you to explain it to them. So I am not sure what all the fuss is about.
I even think most people here can understand why what you did works. Quite possibly they don't even need you to explain it to them. So I am not sure what all the fuss is about.
Most people understand it in terms of the gibberish?
Or, they understand in conventional terms?
Here's my proposal. Someone other than Joe please explain why his speaker has very flat frequency response, why it also has flat impedance and then why it has equally flat response in voltage drive and current drive (sorry, 240 ohm drive).
That's good to start off with, if something else comes up we can expand as necessary.
That's good to start off with, if something else comes up we can expand as necessary.
Missing TAA 03, TAA 04 TAA 0n. I don't know if it is current or voltage yet. @ 50/50...but I want to read through the whole article. (Pause)
RE: TAA 02 For the JBL D-130? I'm thinking you made a notch filter to coincide with the rise in driver impedance.
And then had to find a way to load the speaker. I'll have to look at a C40 box and see. Or did you use that .47 ohm resistor in series with the voice coil to load the speaker and amp it that way?
Or change the Box parameters make something smaller to so that there was cabinet loading to make the amp work harder.
Now that I think about it, It has to be current because speakers are current driven.
Voltage is potential, but not work. Current is work, there ore we need a low distortion current driver.
NOTE:You've got my email, can you just sent the whole file to that, please? I was going to post a few other articles but they were too large also. You might want to check your span filter there might be mail in there.
At least for now. Let me burn through some physics youtubes.
Cheers,
Post Script, So I'm looking at TAA05. I think Q15, & Q16 designator's should be reversed, not the devices but just the numbers...why? The MJ15003 (2) +50V side, the (2) for even? Nope, never mind, the (2) is for two devices as I see MJ15004 designator is shown twice. Never Mind.
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You missed the point, Keantoken, in this case the negative resistance is generated to cancel the primary resistance of the output transformer that the oscillator drives, lowering its low frequency distortion considerably. Of course, only so much negative resistance is allowed or you create a secondary oscillation. This is what we call 'serious design' and we master designers give approval to whoever does it.
John the inmates have temporarily taken over, I'm not sure recovery is possible.
So, if the universe is 85% dark matter... why couldn't that be the space that surrounds the nucleus? And it's why electrons don't collapse down into the Protons & Neutrons? Perhaps it's so ubiquitous that Einstein couldn't complete his unified field theory because everything is immersed in dark matter to begin with.
It flows through us, through the universe, etc.
Is that the other consciousness that we as beings try to connect with but just seem that we can't? We the fish in the sea but can't see the sea. What's the other 90 percent of our brains doing? Does it connect us all? Like Whales connect through the oceans click, bale, communicate.... so perhaps we too, thru dark matter, the other reality.
Anyone going to ALIEN con?
I want an autograph from the researchers/presenters of our Alien past. Sadly, man wasn't smart enough to do these things on our own, we needed "seeding".
...Without any clues.
Working on the night moves.
I want an autograph from the researchers/presenters of our Alien past. Sadly, man wasn't smart enough to do these things on our own, we needed "seeding".
...Without any clues.
Working on the night moves.
Some Movie said:
Someone trying to be funny said:
Some Lieutenant during FTX said:
Some guy who's name's in the thread said:
Oh no said:
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No.
For dark matter to prop up electrons... There are so many problems with that. Why would they be racing around? While it might take a long post to explain everything, for what you say to be true it would erase centrifugal force as we know it. And by doing so you'd probably be making electricity impossible. Electrons don't stick to the nucleus because they develop kinetic energy as they get near it, which makes them move faster and that forces them out. There is a relative balance created between kinetic energy and charge attraction. It can be modulated by a few things. I'm sure you have heard of "electron cloud" this is the balance zone.
(I have some thoughts on what dark matter may be doing, but won't share unless requested)
Also the whole 10% thing has thoroughly been disproved.
An externally hosted image should be here but it was not working when we last tested it.
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I have a perhaps silly question about DC servo.
Take an example of an opamp such as ADA4522 to be used as servo, with an R of 1M between amp output & opamp -Vin, and a C of 1µF between opamp out & -Vin. Opamp +Vin is referenced to Gnd.
The opamp is specified with a noise spec of 120nV (input referenced) between 0.1 to 10Hz. Now, at 0.1Hz, our servo has a gain of -1.6. So does it mean that the noise contribution of the DC servo itself is ~200nV at the opamp output ?
Thanks in advance, Patrick
Take an example of an opamp such as ADA4522 to be used as servo, with an R of 1M between amp output & opamp -Vin, and a C of 1µF between opamp out & -Vin. Opamp +Vin is referenced to Gnd.
The opamp is specified with a noise spec of 120nV (input referenced) between 0.1 to 10Hz. Now, at 0.1Hz, our servo has a gain of -1.6. So does it mean that the noise contribution of the DC servo itself is ~200nV at the opamp output ?
Thanks in advance, Patrick
Physics is pretty straight forward but it's easy to get confused by some folks' ambiguous narratives. Everything electrical is current driven, voltage and current go hand in hand. Current is not work. Voltage is not work. Current x voltage is work. 🙂
In your article, why do you say that modern voltage amplifiers work on the assumption that speaker impedance is fairly constant with frequency?
No Chris, in no way am I suggesting that. But thanks for asking rather than make the assumption.
Actually, I recall Nelson Pass saying something along the line of getting a voltage amp that can swing decent amount of voltage swing and then add a series resistor of x5 value or so, to simulate current drive. I have tried that in front of an audiophile crowd and a Hypex 400 Class D amplifier and it did work OK. But this has never been my preferred way. I did it more for fun than anything else - to humour the crowd. 😀
Being 'resistive' is closer to what I am saying. A perfect resistive load is one that draws the same current at all (or broad range of) frequencies. Such a load will have a flat impedance and a flat current phase angle. I have been doing this for some time and more recently went to Europe and found like minds, there are now several speaker manufacturers in Holland after being informed and pursuaded by Hans van Maanen, a physicist, that this is a good idea. He also designs high end amplifiers (with regulated power supplies) and speakers (Temporal Coherence - Natuurlijk geluid dat je raakt... - Home) and believes using current EQ and making the load more resistive is good for the amplifier. We and others are now having a discussion: Is there proof that the speaker also benefits? The answer seems to be yes, as shown by a Menno Vanderveen at European Triode Festival demonstrated a Hypex NC Class D amplifier that he had modified, switchable zero, 8 Ohm and 18 Ohm, that with a PWM amplifier, the difference was heard easily. This would indicate the speaker was benefiting. The link to his subsequent article is here http://mennovanderveen.nl/nl/download/download_6.pdf.
So all I am saying is that an interesting discussion about this topic is definitely under way. I am certainly interested and I hope others are. There is scope here for people to express their opinions and even to add to the subject. So Chris, what do you think?
Below I will show what my Elsinore Mk6 speakers are capable of, the Yellow trace is the amplifer's voltage and the Purple represents the current of the amplifier (using 0.1 Ohm current sense resistor), at 2KHz.
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Well I've thought about it and I have a theory about the reduction in distortion in Marsh's paper.
In the bass reflex cabinet, the E-braking of the driver resists the moving mass of the air in the cabinet. I propose that the increased force on the diaphragm caused greater deformation and thus distortion, in addition to whatever nonlinearities were present in the braking system to potentially distort the back-EMF.
With the motional feedback mod, the speaker has no damping and so it moves more freely with the air mass, experiencing less stresses.
I think I have calculated the output impedance of the motional feedback mod as 2.8R. Don't know if this is high enough to cause the change that is shown. Should I assume the measurements were taken at the same output levels at the given frequency?
Perhaps the motional feedback test had more damping in the box?
In the bass reflex cabinet, the E-braking of the driver resists the moving mass of the air in the cabinet. I propose that the increased force on the diaphragm caused greater deformation and thus distortion, in addition to whatever nonlinearities were present in the braking system to potentially distort the back-EMF.
With the motional feedback mod, the speaker has no damping and so it moves more freely with the air mass, experiencing less stresses.
I think I have calculated the output impedance of the motional feedback mod as 2.8R. Don't know if this is high enough to cause the change that is shown. Should I assume the measurements were taken at the same output levels at the given frequency?
Perhaps the motional feedback test had more damping in the box?
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