In Line FRI Filters?

[Dylanthecat]

Hi All, I have been reading numerous forums re 'noise' in power supplies.

Looking on the RS site there are numerous in-line RFI/EMI filters at reasonable costs. Matched with a quality shielded cable and mid range IEC UK sockets are there any gains to be had? Has anyone experimented in this area?

Many thanks, Martin

[jandl100]

These?

https://i.ebayimg.com/images/g/v9wAAOSwS9Bblie8/s-l1600.jpg

They come in a range of sizes.
Cheap as chips (especially if bought from China) and can be very effective.
I've been experimenting with them recently and they seem to improve imaging and soundstage depth quite noticeably.
Put them round cables from SMPS to start with.

[Dylanthecat]

Hi Jerry - something like this -24176

They are sometimes referred to as 'chokes'. Martin

[Yomanze]

IME these kill the sound... (in-line mains filters). Especially on power amps. I prefer no filtering at all.

[Yomanze]

These?

https://i.ebayimg.com/images/g/v9wAAOSwS9Bblie8/s-l1600.jpg

They come in a range of sizes.
Cheap as chips (especially if bought from China) and can be very effective.
I've been experimenting with them recently and they seem to improve imaging and soundstage depth quite noticeably.
Put them round cables from SMPS to start with.

This is a much better idea than using mains filters. I have a few ferrite clamps on my cables.

[Barry]

This is a much better idea than using mains filters. I have a few ferrite clamps on my cables.

The ferrite clamps shown form a localised series transformer between the L and N wires of the mains cable. They will, of course, increase the inductance locally where fitted and hence effectively act as a filter, and in doing so will increase the source impedance of the mains supply.

However none of this ought to make much, if any, difference to the sound of your gear, and they are a simple, cheap and reversible way of trying out an idea which many find to be beneficial.

(If the cable is thin enough, one can clamp the ferrite shroud around a full cable turn or two; increasing the transformer/filter effect.)