Re moisture and caps. I have discussed this before. Might be needed again;
Any air which get into the cap plates will eventually cause oxidation of the metal plate. For met.film that plate is so thin that effectively plate area is diminished as oxidation consumes area because the oxide is an insulator. The end result is a slowly lowering of the C value over time.
This affect has been seen and measured. It is real for caps with stranded leads .... should not be bought as air (and moisture) leaks inside between the strands.
Vibration affects with caps is simply due to high speed manufacturing methods. Time is money. The faster you can wind the cap, the more can be made per day. BUT, air is trapped between layers this way. That air space allows for physical movement as well as lowered break down voltage.
A well made cap is wound slowly and after wards some will heat anneal them and press out any air trapped. But that increased performance and reliability costs more time and money to make.
THx-RNMarsh
Got Bass ? Think you got bass?
🙂
See if your system reproduces the 5th string on bass intro to the song....
Baby Did a Bad Bad Thing.
by Chris Isaak.
-Richard
Ed, I dissuade people to purchase from any company that shows clear deceptive marketing ploy, no matter how useful the product turns out to be. It is considered a criminal activity by the law here in my backward neck of woods.
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You are welcome.
My motto is, when you stop learning, you die.
Or might as well.
If I am successful at v-tapping this driver with a co-wound coil, I will do some rudimentary tests. But then, I will send it to somebody with better equipment for audio testing**. I can do the inductance stuff, but not distortion and response stuff. I'm willing to pack and ship to somebody willing to further the cause. And, I don't have the room to store stuff.
I will keep the fixturing I will make for this, but the driver will go.
This is a diy forum, so many here have so much to contribute.
Jn
**except Ed..I don't like him..😀
You are welcome. It was a surprise to find it, Google search continues to improve.
If my dissection/redo is successful, I will send the driver to someone else on this side of the pond for more testing.
I will then purchase a second, redo it, and would like to send it to some arbitrary location in Prague, should you be willing to further the cause..I value your expertise.
Course, it does depend on whether or not I can do the tap winding. I do not look forward to neglecting coffee just so I can work under a microscope.😉
Jn
The iron powder one ?......the trick is to to 'cleanse' the sound, ie increase the dynamics and bottoms/mids and without killing the high-end
Dan.
Ed, serious question - and you and plenty others here know I only dip my toes into this here **** storm of a thread to challenge Folks respectfully - but do you have some measurements?
If you have iron filings suspected in some sort of plastic or putty type base and you wrap that around a cable, you have a common mode choke similar in effect to a clip on ferrite (I bought about 10 a few months ago to experiment with) so the effects should be clear on measurements.
If you have iron filings suspected in some sort of plastic or putty type base and you wrap that around a cable, you have a common mode choke similar in effect to a clip on ferrite (I bought about 10 a few months ago to experiment with) so the effects should be clear on measurements.
There is plenty of time, no hurry. I would guess two or three months.
Jn
Late response, sorry.
The shorting ring tries to prevent change of the flux through it. If the vc is stationary and driven at some frequency, the ring will fight that changing flux.
If the vc has DC, but is moving with respect to the ring, the ring will again fight the changing field, eddy braking. If I power the vc with both LF high excursion and hf low excursion, the ring will fight both frequencies at the same time. But interesting is that the vc is now dragging a hf magnetic field through the ring at some velocity.
My thinking of the 18 inch driving the 8 at very low frequency is how I am thinking to see this dragging and consequential asymmetric behavior.
With a single vc wind Ls/Rs model, all inductance and resistance of the vc is reported as a lump. It is not easy to separate out eddy loss, proximity loss, resistive loss, and conversion loss from the reading. The co wound tap wire sees ONLY the magnet coupling, not the vc resistive losses. So it will see eddy loss and conversion loss, and any inductive effects and energy storage transfer via magnetic field. Subtracting the two voltages, the difference will be the resistive loss of the vc.
That is the Jn drive concept.
The tap signal multiplied by the true current gives us the power stored and returned, while amp V times I gives total power, the diff is system loss.
I am thinking through what other entities we could isolate for measure, as we can also measure drive current.
A work in progress.sorry, edited errors above.. Have to model all this up, it can get confusing.
Jn
jneutron said:
Sorry but the Lenz' law explanation is plainly false if it is claimed to dictate that the ring flux opposes and counteracts the original vc flux. As already shown, these two remain always at 90 degree phase difference, as forced by Ampere's and Faraday's laws and also basic transformer theory.jneutron said:
The ring current and its consequent image current in the primary coil are another matter, and these are really in antiphase so that their magnetic effects cancel out, leaving the original vc flux unchanged (like the magnetizing flux in a power transformer remains unchanged).
Finally, the flux becomes somewhat reduced only by the fact that, due to the increased primary current, the voltage drop in vc resistance becomes more dominant, hence leaving less input voltage for the transformer system.
There are many aspects in driver operation where the popular narrative goes wrong, and this Lenz' law stuff is just one of them.
It was surprising to me a bit of plasticine with anything in it would make a perceived audio change. Iron filings were in two of the samples. One with carbon bits. Only one of the test samples had the strong effect. As I did not remember which was what I will have to look up my notes on the ingredients. At some point I will run curves of frequency versus level from a 10,000 ohms source to a 1,000,000 ohm load.
In the meantime some of the goop will be going out on equipment rentals and performances to see if it reduces EMI.
BTY
The microphone is intended for audio surveillance added to the video inside prisons. LF response is not much of a worry. It has a limiter and distribution amplifier built in using transformer isolated outputs. Power source can be 6-60 volts AC or DC. Current goal is to reduce the internal current drain to allow phantom power.
This is where your error lies. It is not the magnitude that is being opposed, it is the rate of change that is being opposed.
You are welcome to your opinion that lenz's law is wrong, but I'd personally go with the dead guy.
You have actually shown nothing. You have disagreed with Lenz's law, but nothing else.
As I said, I'll stick with the dead guy until such time that someone with actual facts and measurements proves Lenz's law is incorrect.
Jn
Isn't that just a misunderstanding?
IMO ETM did not assert that Lenz's law is wrong but just that the explanation of the 'ring effect' using Lenz's law was incorrect.......
I hate this IPad. Something times out and when I hit submit reply, it asks for login and completely erases my post.. So,I have to quickly save the start of the post, then edit a little at a time saving all along, so pardon the continuous build.
He is arguing that the vc field magnitude is not affected, that is a diversionary argument.
Lenz effect is the creation of a magnetic field which bucks the time varying component of magfield trying to go through the ring. That time varying field is 180 degrees from the time varying component of the vc field. The vc sees a reduced field because the total time varying magnetic field which is the sum of the two, is reduced.
We see this at work with our HTS solenoids when we ramp them. The inductance is reduced during ramp because of the stainless and copper structure around the solenoid and all ring like end pieces.
When ramp is done, all the inductance returns. In addition, the end structure has significant axial forces during ramp which disappear when ramping stops at full field, 12 to 25 tesla give or take.
ITER also fights this(which is actually when I invented this tap scheme.)
CERN also fights both Lorentz as well as Lenz based forces and reactions on their beam screen in their magnet bores. In the LHC, they have little Lenz reaction during ramp up, as that is when they are accelerating the beam and the ramp is limited by the RF power they have available for accelerating the beam. But if a quench occurs, they have to drop the field very fast so the magnets do not burn up. It is during that ramp down that Lenz exclusion rears it's ugly head.
So this shorting ring/inductance drop and forces are completely understood, modeled, and accounted for. That paper I linked to...dead on. My problem is in the explanation to people who are outside my work domain. I constantly learn here how best to explain by the disagreement and discussion with the rather smart people here.
Jn
Done..phew..
I think I just figured out the disconnect.
ESA is a current drive kinda guy.
I am a voltage drive kinda guy.
When I measure inductance, I drive a voltage and measure the current which is 90 degrees lagging to begin with.
I believe ESA is skipping that part simply because of worldview.
Jn
Interesting, all the shorting ring patents.
The JBL patent filed April 9 2003 very cleanly states that the voice coil inductance is lowered due to the shorting ring proximity..
Sorry that I cannot provide a link with my IPad.
Whew, finished my workout...
Jn
Good Cap input, Richard. We all should be reminded of all the things that make caps the compromised devices that they are. You are a great source, because you worked so closely with REL back in the past. As a summary, we know that caps have Dielectric Absorption, some just a little, some a lot! Unfortunately, the low DA caps often cost the most, and are large for their capacity. However, all else in DA, being equal, other factors are very important too, like their inherent damping from external vibration, internal connections and lead material. Your point about STRANDED LEADS being an air leak source is informing. I had some caps COMPLETELY change their value, just while sitting in a drawer for a few years. Made them completely useless. Yup, stranded leads!
In my opinion, phono EQ is very dependent on the cap choice of the designer. Beware, of cheap choices, that look like they may do the job.
In my opinion, phono EQ is very dependent on the cap choice of the designer. Beware, of cheap choices, that look like they may do the job.
In addition, conductive coating exists as paints, and you can buy cables with outer jacket with embedded rfi properties. And, plastic shrink tubing with rfi properties. ETC.
-RM
And as goop or paste:
Conductive Paste | Siltech Corporation Inc. | Manufacturer in Gottigere South Avenue Layout, Bengaluru | ID: 4483213197
-RNM
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