You are on the record with a lot of sighed listening tests yourself, which means peeking included.
And, if the results are as you expected, you're perfectly fine with this procedure.
Depends on the precise definition of 'sighted' ; if the term 'sighted' denotes 'knowledge about specific properties of identifiable devices' then in reality a listening test using a qualitative or quantitative approaches can be done and give correct data although 'peeking' is happening... 🙂
First thing I notice is that the graph makes no sense. Apparently positive current causes both positive and negative excursion. It seems they couldn't figure out the difference between a force-excursion chart and a spring constant chart.
Second, that graph is hand drawn and generated... which tells me they have no actual data they could have shown, which would have also come with the knowledge of how to draw that chart in a sensible way.
Referring to amps as energy...
The page says 99.5% linear... which is an evasive way of saying it has 0.5% THD.
Throw in Klippel reference at the bottom, which after following this questionable article begins to look like a hollow name drop. If they are really up on Klippel then why don't they already have Klippel system suspension measurements to use in their article?
CFA stuff again
“Doesn't matter, changing Rg has exactly the same effect as Rf, of changing the open loop gain. If you look at the basic CFA model after breaking the feedback loop (and considering the feedback loop elements loading), Rf and Rg are in parallel and their combination is defining the open loop gain.
Pole splitting is off topic, but because you mentioned it, a CFA may get more bandwidth but definitely not more loop gain compared to a VFA. The amount of loop gain is set by the Bode's maximum feedback theorem, which doesn't make any assumptions about any feedback configuration. See for example 404 Not Found
The extra bandwidth in a CFA boils down to the JC fetish with the open loop bandwidth, and argument that I despise. It is totally irrelevant from any audio or non-audio perspective.” [syn08]
I made the point that you adjust the value of Rf to compensate a CFA since that sets the front end gm. You then can have a lot of freedom in setting the gain by adjusting Rg keeping in mind that the gain sweet spot holds over a fairly narrow region.
I mentioned pole splitting because is a useful way of comparing it to typical a CFA compensation. In a typical VFA the loop gain is high and if you don’t apply suitable comp (eg pole splitting) the phase shift at the ULGF will be in excess of 180 degrees and therefore unstable. In a classic CFA with moderate OLG, you don’t have as much phase shift and you only need very light compensation to ensure stability. The result is you can have very wide loop gain bandwidths.
You can ‘pole split’ a low OLG CFA but the result is totally suboptimal because you are throwing away loop gain at HF.
You can have as much loop gain as you like as long as you manage the phase shift at the ULG intercept ergo MIC, OIC, TPC etc (as per the paper you linked to that in fact show exactly this approach). Dadods designs for example have loop gains in excess of 80 or 90 dB and wide loop gain bandwidths (a result of his comp design).
If some have a fetishes about ‘wide loop gain bandwidths’ so what? Some folks drive to work in a Mustang, others prefer a Corvette. I personally don’t see any reason to worry about it or despise it. These are design choices and in any non-critical application with lots of degrees of freedom are driven by subjective opinions of the designer (Mustangs vs Corvettes again).
“Doesn't matter, changing Rg has exactly the same effect as Rf, of changing the open loop gain. If you look at the basic CFA model after breaking the feedback loop (and considering the feedback loop elements loading), Rf and Rg are in parallel and their combination is defining the open loop gain.
Pole splitting is off topic, but because you mentioned it, a CFA may get more bandwidth but definitely not more loop gain compared to a VFA. The amount of loop gain is set by the Bode's maximum feedback theorem, which doesn't make any assumptions about any feedback configuration. See for example 404 Not Found
The extra bandwidth in a CFA boils down to the JC fetish with the open loop bandwidth, and argument that I despise. It is totally irrelevant from any audio or non-audio perspective.” [syn08]
I made the point that you adjust the value of Rf to compensate a CFA since that sets the front end gm. You then can have a lot of freedom in setting the gain by adjusting Rg keeping in mind that the gain sweet spot holds over a fairly narrow region.
I mentioned pole splitting because is a useful way of comparing it to typical a CFA compensation. In a typical VFA the loop gain is high and if you don’t apply suitable comp (eg pole splitting) the phase shift at the ULGF will be in excess of 180 degrees and therefore unstable. In a classic CFA with moderate OLG, you don’t have as much phase shift and you only need very light compensation to ensure stability. The result is you can have very wide loop gain bandwidths.
You can ‘pole split’ a low OLG CFA but the result is totally suboptimal because you are throwing away loop gain at HF.
You can have as much loop gain as you like as long as you manage the phase shift at the ULG intercept ergo MIC, OIC, TPC etc (as per the paper you linked to that in fact show exactly this approach). Dadods designs for example have loop gains in excess of 80 or 90 dB and wide loop gain bandwidths (a result of his comp design).
If some have a fetishes about ‘wide loop gain bandwidths’ so what? Some folks drive to work in a Mustang, others prefer a Corvette. I personally don’t see any reason to worry about it or despise it. These are design choices and in any non-critical application with lots of degrees of freedom are driven by subjective opinions of the designer (Mustangs vs Corvettes again).
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I can completely guarantee effective noise reduction from that formula when placed in the right place. Roll two small balls of it into tubes. You can even do an AB test to confirm this works. Try it both ways. Tubes unattached and then place them in your ears. Voila instant noise reduction. 😉 !!!!
Others may want to try it on power and interconnect cords!
“The page says 99.5% linear... which is an evasive way of saying it has 0.5% THD. ”
Reminds me of the biscuit and snack adverts here a few years ago saying ‘Go ahead - they’re 90% fat free’.
They were hauled up by the advertising standards authorities and the practice was banned.
Reminds me of the biscuit and snack adverts here a few years ago saying ‘Go ahead - they’re 90% fat free’.
They were hauled up by the advertising standards authorities and the practice was banned.
Here is the article Syn08 linked.
https://ukacc.group.shef.ac.uk/proceedings/control2004/Papers/063.pdf
https://ukacc.group.shef.ac.uk/proceedings/control2004/Papers/063.pdf
I thought that was one of Rupert Sheldrake's bizarre ideas...
Oh, I don't know... Feels more like joining in the fun... 🙂
Yes, not many get really angry, he's like a naughty puppy, boring after a while but you have to smile.
There are more serious fudmongers here who actually sell stuff
There are more serious fudmongers here who actually sell stuff
It raises resistance, but at a net loss of impedance.
Relative to the bulk series resistance, skin effect increases resistance. Relative to the bulk shunt resistance, skin effect reduces resistance. We are talking about different elements in a lumped model. A lot of confusion seems to come from this. People tend to think of the series resistance but then treat it as if it were the shunt resistance and vice versa.
In skin effect, the measured inductance is closest to the bulk inductance at the low end of the skin effect BW. This is why it makes more sense to think of skin effect as shunting inductance. If you think of it as in series with inductance then you end up needing a negative inductance effect to explain how a series impedance reduces overall impedance.
Also in the flux model, the eddy currents do indeed shunt inductance.
When you think of skin effect as shunting the bulk inductance, then you can start with the bulk inductance in the model and divide it up with shunt resistors.
If you think of skin effect as in series with the inductance, you can't even construct a model because inductances and resistances in series just add to a large inductor and resistor.
So while the skin effect at a SINGLE frequency can be thought of as an inductance with a series resistance, this is only the "dumb" RLC meter characterization which has no explanatory power for the physical system.
Relative to the bulk series resistance, skin effect increases resistance. Relative to the bulk shunt resistance, skin effect reduces resistance. We are talking about different elements in a lumped model. A lot of confusion seems to come from this. People tend to think of the series resistance but then treat it as if it were the shunt resistance and vice versa.
In skin effect, the measured inductance is closest to the bulk inductance at the low end of the skin effect BW. This is why it makes more sense to think of skin effect as shunting inductance. If you think of it as in series with inductance then you end up needing a negative inductance effect to explain how a series impedance reduces overall impedance.
Also in the flux model, the eddy currents do indeed shunt inductance.
When you think of skin effect as shunting the bulk inductance, then you can start with the bulk inductance in the model and divide it up with shunt resistors.
If you think of skin effect as in series with the inductance, you can't even construct a model because inductances and resistances in series just add to a large inductor and resistor.
So while the skin effect at a SINGLE frequency can be thought of as an inductance with a series resistance, this is only the "dumb" RLC meter characterization which has no explanatory power for the physical system.
Yes, an N48 supermagnet that can lift 50lb has no effect on an LCD display.
Don’t understand why this was brought here. This is not a good place to have a discussion about anything but Bybees and Goop.
You forget that I'm more interested in the claimed mechanisms that defy known physics. Besides as I keep pointing out many even possibly most claims are stated in extremely exaggerated fashion, you would have to be deaf, etc., so why should I go through the bother?
Have you forgotten blind testing (the only reason Jakob comes here) or are you trying to forget blind testing, imagining that only a select few actually give much of a toss?
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