I forgot the new XLR was shield to shell.
But the idea is still valid.
Cap from Hot to Cold becomes the second half of the LC filter.
And the lower the HF impedance of the cap connection the better the filtering effect of the Cap.
I see your diagram showing two smd caps spanning the gap between the Hot pole and the Cold ring of the plug. I think it might be better to fit the caps to the back of the input socket. Or maybe fitting a cap at both plug back and socket back could be better still. I use 47pF, not 10000pF (=10nF = 0.01uF).
At the speaker end, I have used 1nF for both speaker terminals to Chassis. I also use ~4r+150nF (series, not parallel) across the speaker terminals.
I found it quite fiddly to solder, but persistence paid off and it worked even though the cap must have been severely overheated.
I checked capacitance with a meter after I completed the single cap soldering/installation.
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the filter is attenuating interference from the cable.
The filter MUST be at the Receiver Input.
ferrite around the two wires of the cable very close to the chassis socket.
The cap very close the the back of the socket to minimise the length of unfiltered cable that would radiate into the inside of the Chassis.
Why stop at mm/mc - why not line in, aux, tuner, casette 
I see. Thank you.
I know simple ceramic is the best for that purpose, but the only 47p that I have in home is Polystyrene. I might find silver mica...
Both not SMD. If SMD is mandatory better, then I need to go to Mouser... Will take 2-3 days to get it.
To look for ceramic SMD in Mouser or I might use one of these that I have in-hand?
I found a 100 m roll of this Bedea coax btw https://www1.elfa.se/data1/wwwroot/assets/datasheets/cf080xCA-140xCA_d-e.pdf. About a euro per m on standard sale, thin and very easy to work with. I measured it up and it sticks to 102 pF/m without deviations between 100 Hz and 100 kHz. I think I'll go with that one on internal mV signal cabling.
Hi Nick,
Thank you very much for your advice to use scope.
I imminently found the reason of my sudden signal sense turn on for my sub.
BTW, it might be a good lesson for all other guys who use small bypass caps on main AC switches.
So, I connected scope and turned Linkwitz On. Adjusted scope to see "0" signal and off position introduced noise in signal. Disconnected power cord from Likwitz and oops..., noise gone. Repeated several times and same thing. Noise when Filter is not powered.
I accidentally turned room light off and my main power switch (it has an internal LED) was showing some light. It was dimmed, but definitely light was there.
So, long story short: I used ERO Vishay 1817 10n 250v cap as a bypass for main power switch and it was leaking. I had 0.5V on my filter during power off.
I removed it and Voila!!!
Thank you very much for your advice to use scope.
I imminently found the reason of my sudden signal sense turn on for my sub.
BTW, it might be a good lesson for all other guys who use small bypass caps on main AC switches.
So, I connected scope and turned Linkwitz On. Adjusted scope to see "0" signal and off position introduced noise in signal. Disconnected power cord from Likwitz and oops..., noise gone. Repeated several times and same thing. Noise when Filter is not powered.
I accidentally turned room light off and my main power switch (it has an internal LED) was showing some light. It was dimmed, but definitely light was there.
So, long story short: I used ERO Vishay 1817 10n 250v cap as a bypass for main power switch and it was leaking. I had 0.5V on my filter during power off.
I removed it and Voila!!!
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Use X class capacitors for such purposes.
X2 is normally used on single phase 220/240Vac systems.
X2 can also be used on 110/120Vac systems with extra Factor of Safety (FoS).
X1 is normally used on 3phase 400/440Vac systems.
X1 can be used on 110/120Vac and on 220/240Vac systems with extra FoS.
The MKP 338 example in post14606 is an X1 rated to 440Vac.
You can use this cap, but an X2 is good enough for single phase systems.
X2 can also be used on 110/120Vac systems with extra Factor of Safety (FoS).
X1 is normally used on 3phase 400/440Vac systems.
X1 can be used on 110/120Vac and on 220/240Vac systems with extra FoS.
The MKP 338 example in post14606 is an X1 rated to 440Vac.
You can use this cap, but an X2 is good enough for single phase systems.
I still have 0.01uF Vishay MKP F1778 which left from my Main AC Filter project. They rated X2. Based on your explanation, I can use these with no issues. Right?
F1778310M2DCB0 Vishay / Roederstein | Mouser
F1778310M2DCB0 Vishay / Roederstein | Mouser