Woody wrote:
"Serge Auckland" wrote in message
...
I'm trying to improve the frequency response of my V15III/SME 3009 S2,
and remember that Shure or SME had a little equaliser circuit that
flattened the response at the expense of a couple of dBs of output.
Something may have been published in HFN and/or Wireless World in the
'70s, but my HFNs don't go back that far, and I can't find it in my
WWs of the era.

I've been searching on-line for the circuit all afternoon, and can't
find anything. It was simply a capacitor and a resistor or two, but I
can't remember the configuration or values.

Does anyone have this info please?

Thanks

S.


--
http://audiopages.googlepages.com


Ah, now this is one I do know about - it applied more or less across the
Shure range.

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. Adding an extra 200pF to the basic cartridge and wires
will increase the level at 10kHz by about 2.5dB. This is all about the
way the capacitance resonates with the inductance of the cartridge.

d