Phil Allison wrote:
"Don Pearce"
Woody wrote:

Shure cartridges were designed to work into a load of 47K resistance
(like all others) in parallel with something around 360pF capacitance.
The pickup arm cables and the interconnect to the amp would account for
about 120-150pF, which leaves the cartridge underloaded and thus rather
peaky and bright.

The way the impedances work out, you get more peakiness as the load goes
up, not down.


** Shure V15IIIs definitely sound brighter with less loading capacitance -
and or an increase in the load resistance above 47 kohms.


Adding an extra 200pF to the basic cartridge and wires will increase the
level at 10kHz by about 2.5dB.


** Don just plucked that figure out of his bum.

The real number is about 0.5dB at 8 to 10 kHz.

So barely audible.

What an extra 200pF * DOES * do is drop the response at 14 - 17 kHz by 3
or 4 dB - and THAT is what a person with good hearing notices as "
duller ".


This is all about the way the capacitance resonates with the inductance of
the cartridge.


** For anyone who cares to simulate the situation, a V15III has the
following :

L = 550 mH.

R = 1370 ohms

Fo = 42kHz ( equates to about 25 pF internal C )



..... Phil







I did the simulation two years ago and the results are still he

http://81.174.169.10/odds/v15iii/cartridge.html

For some reason this page doesn't work well in IE (saved as HTML from
Mathcad), but use Firefox and it'll be fine. It shows how peaky the cart
gets with added capacitance. And of course a 3dB peak at 10kHz is going
to beat flat extension to 20kHz any day when it comes to sounding bright.

d