"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 answer - provided you have the skills to do it - is to make up two
short phono plug-socket link cables perhaps 3-4in long and fit a 220pF
capacitor inside one of the connectors in each cable. A small ceramic
capacitor of that sort of value should be no more than about 4mm square
and will fit quite easily. Remember capacitors are additive in value
when they are connected in parallel.

Total cost with components from Maplins would be about £5. There used to
be manufactured units that did the same thing and cost about £30
apiece - much the same thing with mains spike protectors which cost
about £5 to make (retail) and sell for £100++, especially those from
rip-off Russ. You may have to dig a bit to find the capacitors though.


--
Woody

harrogate three at ntlworld dot com