And yet, incorrect. There are two impedance rises in the graph.
The impedance peak at 100 hz or so is a mechanical one, not a consequence of the voice coil inductance. Below it a standard inductance meter measures it as a negative inductance, and the rise to peak impedance is a consequence of system Q, or more specifically, the system's energy storage response.
If you want to see voice coil inductance, you have to look at the graph from the minima above the resonance on up in frequency, and more specifically, the coil has to be locked.
If you want to see the voice coil inductance more clearly, place that driver on it's face so that the air trapped between the cone and the surface acts as a locked coil system. There will be some interference with the real inductance as the simple fact that there is an air cushion allows some movement of the coil.
But the amp and wire does not see just the voice coil inductance. It sees that as well as the energy storage characteristics of the speaker in box through the audio band, with less box as frequency rises away from peak.
See, no flogging.
John
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No just misread. We agree on the causes but you seem to think I confused the resonance peak with the inductance rise. You also got the issue of why the inductance rise is not a straight line. There is also a change in loading. With a bit of work you could estimate the efficiency.
Now the impedance peak will of course combine with any impedance variation from the theoretical power amplifier output to produce a deviation in power delivered to the loudspeaker.
Common practice is to correct frequency response deviations with equalization. Yet that will not work on this type of resonance.
Now the impedance peak will of course combine with any impedance variation from the theoretical power amplifier output to produce a deviation in power delivered to the loudspeaker.
Common practice is to correct frequency response deviations with equalization. Yet that will not work on this type of resonance.
It was a mixed bag. I didn't hear much of a correlation in sound quality between 16/44 and hi res demos. The turntables and tape generally sounded inferior in the few cases I was able to actually hear both TT/RTR and digital. But low statistics, nothing controlled, so I wouldn't draw any conclusions.
The very best sound I heard was a room that used a mix of hi res and 16/44, but the quality was from the close attention they paid to room acoustics and the excellent speakers. The very worst sound I heard was in a large room that may have been acoustically pretty good, TT as source, nice electronics, but I think the speakers let everything down.
Precisely who the hell do you think you are? You are just a customer - know your station in life and follow procedures.
Now if you're an investor or even better still an analyst that's an entirely different story. We are here to serve you.
Yes, I did. Volume too high, tipped up bass. Very hifi-show sound. Probably could sound very good if it weren't being demoed.
Attachments
Good to see they have not changed in 25yr. JC would say it's what the guys "who know where the action is" want.
https://www.youtube.com/watch?v=V77Di0KZrSU
Ed it would help if you had at least enough respect for the technical community at large that you would collect the literature on this and go through it, it is substantial, before presenting issues like no one has ever thought of them before.
I do this every week the "peanuts" go off like nothing before has ever happened and I reel them in with hours of readings from the past. Just call me Buffalo Bob.
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A quote I first heard attributed to Lotfi Zadeh but I doubt he originated it :
Friends may come and go, but enemies accumulate.
Reading this Moving on Up at AXPONA | Stereophile.com was horrified that the Wilson Audio demo used $208k worth of cables and power conditioning. As if 100k speakers and a 100k DAC wasn't bad enough!
Good grief. For that you could build a new house with a custom designed listening space, and fill it with a decent hifi system,.... Now *that* might be worth it...
You guys have no imagination. Those potential customers already have a new house with dedicated listening space and a good system. 🙂
Jan
It sounded OK, nothing special, FWIW. Too bad they didn't put that same effort into the important things sonically, but they know what their prospective customer expects.
I have once tested maybe 80 or 100 devices and they were nearly all 12-13 mA, very few outliers by more than 2 mA when I wanted some high Idss ones.
It goes without saying that they were not that consistent when I needed similar ones for a differential amplifier.
Fet-aided op amp:
<http://www.analog.com/library/analogdialogue/archives/47-10/discrete_amplifier.pdf >
regards, Gerhard
(You guys have no mileage. Those potential customers had the dedicated listening space altered halfway down the build of the house)
Last time I had a dedicated listening space was because the wife had left me. And taken all my money...
Are the super rich not still into dedicated home theatres rather than 2 channel audio?
Thanks, Dimitri! I failed to produce the plot with OpenOffice Writer built-in tools. 🙁
regards, Gerhard
Actually I'm surprised someone isn't promising a quantum listening space that's larger than the house it's in.... Funnily enough I just bought some glue and tar solvent called TARDIS....
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