Yes he did. He did call us unwashed amateurs 'pitchfork wielding villagers'. But it's been some time.
jan
OK, everybody, why don't you tell me what your favorite cartridge is, and let's find its optimum capacitive loading according to the cartridge maker? Then let's see how close we are with my 'one capacitance fits all' solution.
We can do the same with the noise of a 'one IC fits all solution' and your phono cartridge as well.
We can do the same with the noise of a 'one IC fits all solution' and your phono cartridge as well.
I am not offended by any of these descriptive words.
I would however by such a compilation: “perfumized professionals Wallstreet money raisers”
My Denon DL-103 starts pulling noticeably over a suspended chain made of steel paper clips from a distance of 30mm (from tip) in all directions.
George
If you have a non-linearity in your magnetics DEMAGNITIZE them. (And if you believe that it demagnitizes them I have a deal on a bridge for you). Keith Johnson and I had a good laugh about that. What it will do is magnetize (if the signal is strong enough) the armature of the coil windings. Whether that will have an effect is questionable but since its practiced with the cartridge off the disk its not happening with the system in alignment. You would also expect the drive to make an audible output from the device. The few times I observed the practice I heard nothing.
I have experimented with passing a current through the windings of an MC cartridge while playing. At the time I thought it improved the sound. I may have been fooling myself. . . It was about 1 mA and the cartridge was a Lyra Parnassus. Give it a try if you can and are willing to. Its risky for major pops needless to say.
I have experimented with passing a current through the windings of an MC cartridge while playing. At the time I thought it improved the sound. I may have been fooling myself. . . It was about 1 mA and the cartridge was a Lyra Parnassus. Give it a try if you can and are willing to. Its risky for major pops needless to say.
Indeed, but therein begins the problem. You'll get ~50pF from the cable and the connector, maybe 10-20 more from other wiring in series (e.g., inside the tonearm, inside the preamp). So with 100pF input capacitance, you're probably OK. But, take a FET input pre or, worse yet, a tube unit with a high mu input tube (very commonly a 12AX7), and suddenly you're at 2-3 times that. It's exacerbated in preamps with switchable multiple phono inputs because of the extra wiring (which is often NOT low C).
Thus my question about the actual input capacitance. It's a pity that this is so rarely specified.
Plus wiring, traces... that's why it would be nice if preamp manufacturers actually specified input capacitance as measured at the input plug. As well, it would be nice to provide easy loading adjustment options. The user can either do it by the numbers or do it by ear.
Wasn't there a pre from some decades back called Klyne which had that sort of flexibility?
Hmmm, I use the LT1358. "somewhat excessive current noise for MM" amongst other criticizsms were flung at the poor little opamp. But I like the sound and many others do too.
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I still think you mis-understand the technical definition of excess noise.
The noise produced by current flowing through the MM Z is not excess noise, it is just another noise source. 2uA has about .8pA/rt-Hz, this times a 1k Z is an extra .8nV/rt-Hz of ordinary noise (with nominally a flat spectrum). It has nothing to do with the already too much thermal noise of the resistance or the voltage noise of the op-amp. The same 2uA produces only 2mV of DC voltage, excess noise does not typically show up before there are volts across the resistance and it has a 1/f spectrum. The paper I linked is an excellent overview of the theory.
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One possible issue with even small DC currents through the phono cartridge happens in some older turntables with muting switches across the signal lines. Pop! Pretty much all changers, like Duals, PE's, etc have muting, and so did B&O and others. DIY'ers can defeat this, but a commercial design would need to allow for it (I'd guess).
Thanks,
Chris
Thanks,
Chris
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