But engineers are smart. No reason why you couldnt connect 2 barreries in series while charging then parallel when discharging. Loss is negligible. Change battery to cap, and you get the switched cap converter. The problem is the discrete voltage ratio set. But with 1 inductor and 2 switches there is no such limitation. This is called ClassD amp. No rule against it.
Not that smart, second law. Google KT/C noise.
Funny there's actually a dark noise band called KTL ****** BY NOISE: KTL - 2
Perhaps this would be a good time to admit that my remark about lossless resistors was uttered with tongue firmly in cheek. It was my response to someone who wanted a motor with no back emf. Next: capacitors which don't store energy.
I dont see any relevance. What is your statement? Mine is: no rule against 100 % power conversation efficiency.
A switched cap filter has the same noise as an equivalent RC filter no matter how you make it.
Or more. But who talked about filters and noise? We talk about power conversation, at relatively high power.
True. Irrelevant. A switched capacitor used in place of a resistor is not converting power, but wasting power - just like a resistor.Pafi said:
We did.
No. You talk about power conversion. We talk about 'lossless resistors'. Someone suggested using switched capacitors instead of resistors - the usual application for this is filters. No matter: anywhere a resistor is replaced by a switched capacitor you will get the same loss.
Would this be of any relevance to the topic ?
Patent US3838216 - Device to effectively eliminate the motion induced back emf in a loudspeaker ... - Google Patents
Regards.
Patent US3838216 - Device to effectively eliminate the motion induced back emf in a loudspeaker ... - Google Patents
Regards.
Then you were offtopic. This topic is about amplifiers and speakers, not about making nonsense jokes about fictional questions. Both noise and switched capacitor filters are offtopic.
An amplifier is basically two controlled resistors between 2 voltage rails. These can be replaced by combination of controlled switches and reactant elements to give basically the same output, but with negligible loss. In this meaning resistors can be replaced by lossless circuit. Noise has absolutely no relevance.
And even if you talked offtopic it doesn't mean you can pretend like others talked the same stupid thing (what you intentionally made stupid).
If all your intention was to show how a troll behaves - you succeed.
Yes you can. It is called a superconductor.
Sorry for staying ontopic...
I remember Philips was one company doing a lot of work with motional feedback back then. The patent lawyers were busy in that area
Someone asked a question about a fictional speaker without back emf. As this is not possible in this universe, was this off topic too?Pafi said:
On this forum the Mods are fairly relaxed about off topic comments, especially when they are triggered by someone else.
"Switched capacitor" is a particular circuit technique used in filters. Nothing to do with high efficiency audio output stages, where capacitance is a loss mechanism.
No. A superconductor is not a lossless resistor. It is quite a different thing: it is not a resistor as it has zero resistance, and it is not a normal conductor because it excludes magnetic fields.
Sorry if my British humour is not appreciated by everyone.
Re current drive of speakers.
What means damping factor if the power amp acts as a current source? The "back EMF" cannot drive any current because a negative feedback of the current source forces total current zero if input is zero ( for example) . Is that dampening?
What means damping factor if the power amp acts as a current source? The "back EMF" cannot drive any current because a negative feedback of the current source forces total current zero if input is zero ( for example) . Is that dampening?
No, that means that speaker is not being damped at all, period.
Same as if the speaker were unconnected.
In fact, one silly trick I play on my customers sometimes which always amazes them, is that I can infallibly detect whether an amp connected to the shop test speaker is ON or OFF without seeing it 😱
I just recite some mumbo jumbo and tap the speaker cone, the undamped/unconnected one thumps like a drum skin, the damped one (amp ON) sounds like tapping a bag full of sand.
Try it yourself 😛
Of course, your proposed pure current amp would fool me
Just a side note: not a grammar nazi but we're talking techglish, and meaning is important: please no conversation for conversion or dampening for damping 🙂
Or that DIYAudio favorite: torroid for toroid.
That said, I can forgive them:
http://www.pulsor.org/#!color-torroid/cqpu
they are talking BS and nonsense anyway.
Irrelevant?
Hey!!! , they even talk EMF !!!!!!!!!
http://www.pulsor.org/#!the-emf-problem/c18tz
unsurprisingly, also in a twisted way 😉
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dampen
v. moisten, wet; moderate, depress, discourage, dull
but but the more important linear motors , e.g. for industry robots, for ex. precise positioning of robot tools relative to the assembly , are all current controlled and must be perfectly damped and are perfectly damped....
how is that magic or misunderstanding of current drive?
the only , say, connection between electrical world and mechanical world
is via B*l*i = ( mechanical) where i current.
all else is in terms of physics sheer nonsense
Which means controlled torque or force. The current has to be adjusted on the fly to give the wanted motion