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    •   Not sure what you mean, but what is apparent is that a loudspeaker Voice Coil has a DC resistance. But it only measures that at DC (0Hz) and at all frequencies above DC, the impedance is higher than the DC resistance. That is the evidence that it is producing voltage.   That voltage, or force cannot be absorbed by the amplifier, because these forces oppose each other. Because the speaker is opposing, this causes less current to be drawn and hence this is reflected in the higher impedance. So if the impedance has doubled due to this effect, the current drawn from the amplifier. Even more, how do you think we measure the impedance? Simply measuring the current changing over frequency and then calculating the current and graphing it, and now you have an impedance plot.   So the more we understand this, the more ludicrous the subject of the amplifier exerting damping properties and that in fact the very opposite thing is happening.   Then we have another factor, the idea that the amplifier can short out effects from the speaker ignores something else. Yes, the amplifier will keep the voltage steady under load and should not change. But something does change. The current changes according to the load. This is fine and does not seem to be a problem, except for this biggie: The current phase angle changes. Not the voltage, the current changes and so does the current's electrical phase angle. What causes it? The speaker. So if the amplifier was a short, then how come that across that short, there is a varying current phase angle changing?   A short is a short. But this is not a short!   Beyond this point it gets into other related matters, such a Trevor mentioned earlier, that feedback can artificially lower the output impedance, but feedback can always (rarely) match the current delivery unless there is some real beef behind that output impedance, and now we come down to device's current capabilities and the power supply. A non-artificial output impedance can match current to go with it.   Trust me, I struggled to get a handle on this as well. But once you grasp the realities of what is going on, then things fall beautifully into place. When none other that Dr. Richard H. Small of Sydney University told me that the whole notion of amplifiers have some kind of ability to add damping, then I was insistent and he became very irritated. I didn't understand it yet, only later when I read the writings of Peter Schneider (I may have his spelling wrong) that made me understand how Thiele's and Small's parameters entirely defined the damping and alignment. It also became clear that I was completely wrong to challenge Small - but I am a lot wiser now.   But the amplifier DF notion will never die down? Who knows?
    • Hi.  I mentioned much earlier that I had ordered a new stylus for my turntable.  Well the LP Gear CFN3600LE elliptical stylus arrived a month ago.  I have been playing many more of my vinyl LPs and have even purchased some more from my local SH supplier.  I am not well versed in these things, but the new stylus certainly sound better than my prior conical stylus.  I have been enjoying the music and playing a variety of genre and styles.   I have a question, although I likely need to raise on a different forum category.  The recommended tracking force is listed below.  My turntable has adjustable tracking force, so can easily accommodate the recommended 2.5 g.  But the anti skating compensation has a range of peg positions, the maximum is 2.0 g.  So I have adjusted the tracking force to match at 2.0 g.  Any comments?   - Tracking force range: 1.8 - 3.5 g
      - Tracking force recommended: 2.5 g (25 mN)
    • A low value capacitor across the input of the phono preamplifier would reduce any RF leaking in at that point.  (When RF gets into a preamplifier, slight non-linearity in amplifying the radio frequency can cause the modulation to become audible. I have heard that effect with AM stations, or the video of analogue TV stations, though not actually with an FM station.) 
    • I would be inclined to buy a stock Lenco GL75, upgraded bearing and Idler wheel, and PTP top plate. Then I would commision someone to build me a slate plinth to put it in.   That leaves about 3k to spend on a tonearm. Might even have funds left over for a speed controller.
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