They can help to reduce mains borne interference and they make a professional, safe way to power your machine. Nothing else.
IME yes cleaning RF out of AC supply does improve sound, best to go for Medical/Low Leakage versions.
Medical grade IEC inlet filters are specified for safety in medical devices (there's no Y capacitors fitted) and the high frequency filter attenuation response (typically above 1Mhz) is actually less than the standard types.
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Leakage currents will only be a problem if connecting a audio amplifier to a patient in a hospital.
There will be a loss of 20db - 50db in attenuation for common mode high frequency noise using a IEC entry module designed for medical equipment, more importantly if your device has a switch mode power supply we don't want the switching noise and associated harmonics radiating of the mains lead.
There will be a loss of 20db - 50db in attenuation for common mode high frequency noise using a IEC entry module designed for medical equipment, more importantly if your device has a switch mode power supply we don't want the switching noise and associated harmonics radiating of the mains lead.
In unbalanced systems earth leakage currents are resolved to signal, SMPS can have relatively higher longitudinal leakage compared to compartmented windings EI or C-core transformer PSU.
For audio systems lower leakage is better, for fridge or washing machine etc leakage does not really matter.
Max.
For audio systems lower leakage is better, for fridge or washing machine etc leakage does not really matter.
Max.
Are there any down sides to using these filters in audio equipment, other than the $15-20 one time expense?
Such as reduced peak power delivery to equipment?
Such as reduced peak power delivery to equipment?
No down sides, these filters are used in all types of equipment including audio.
Just select the module for your AC mains current rating eg: 1, 2, 4, 6 or 10Amps.
Just select the module for your AC mains current rating eg: 1, 2, 4, 6 or 10Amps.
Schurter responded that "too much attenuation cannot be detrimental, the attenuation doesn’t kick in until > 10kHz".
I always use Schurter FKID or DD14 standard version, double pole switched and fused ones, in all my source projects, with the SMD-SPT fuses with the gold plated end caps.
I run a balanced mains power supply which is why I use double pole fuses.
If you do not use balanced mains, one fuse will be fine.
System I have sounds superb, no downsides on using the modules.
I run a balanced mains power supply which is why I use double pole fuses.
If you do not use balanced mains, one fuse will be fine.
System I have sounds superb, no downsides on using the modules.
Most are too small physically, to do much filtering at the frequencies of interest.
But they will keep the higher RFI out.
But they will keep the higher RFI out.
If one has ground loop issues would the filter with "ground line choke" be a good idea?
There are a few models out there.
There are a few models out there.
No, that would make the loop larger (more resistance).
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There are two parts to a ground loop:
1] area enclosed. Multiple paths are a fact of life. But if they all start at the same place, follow the same route and end at the same place, then the area is very small.
2] low loop resistance/impedance. Currents are going to flow in a loop (that's another fact of life) but if the loop resistance/impedance is low than the noise voltage drops will be small.
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No, ground loop noise is/are low frequencies (power line harmonics). Filters don't start to work till near 100 kHz.
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The exception would be common mode filters, but that's not where most of the problems are.
They reduce amplitude of mains spikes which if get through onto secondary can push transistors into breakdown regions and latch up.
I bought some el-cheapo transistors off ebay.
They sounded fine but as soon as I unplugged my soldering iron they blew up! The spike down the mains obviously got through and pushed them into breakdown. I bought some "reputable dealer" same transistors and couldnt blow them up no matter how hard I tried.
Moral of the story is used reputable dealer parts and use a mains filter to protect your amp.