That's nonsense, total nonsense.
They are certified by safety agencies around the world. There are no lifetime limits.
Sure there are things to take into account but let's say that if they would become defective then ... there is a fuse in them.
I have never seen a defective IEC inlet/mains filter but I do have seen defective X and Y caps in SMPS often by brands with unpronouncable names.
About RIFA PME series, the electronic version of Surströmming 🙂 also used in older/very old versions of IEC mains filters:
https://w140.com/tekwiki/wiki/RIFA_capacitors
I have never seen a defective IEC inlet/mains filter but I do have seen defective X and Y caps in SMPS often by brands with unpronouncable names.
About RIFA PME series, the electronic version of Surströmming 🙂 also used in older/very old versions of IEC mains filters:
https://w140.com/tekwiki/wiki/RIFA_capacitors
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When looking at the aging yellowish plastic housing of the decades of old caps the first intent is to replace them:
It would be nice to know when the problem was solved. And how to read the datecode.
BTW cracks in the PME’s casing is a clear sign.
BTW cracks in the PME’s casing is a clear sign.
To handle higher current, the common-mode choke must be made with larger diameter wire, and maybe a lower permabilty core to avoid saturation. That leads to lower inductance, and therefore less attenuation of noise.
Well, I've gone ahead and bought the ones in my o/p.
After wiring one up in my amp I can report that it made no difference at all.
Cheers anyway guys.
Rik
After wiring one up in my amp I can report that it made no difference at all.
Cheers anyway guys.
Rik
I expected veils to be lifted etc... 🤣
No, on a serious note, there is a low level noise coming through the speakers on my new (to me) valve amp. It's almost like a faint static type sound..
I don't know if it's the valves or something else..
Measured difference or by ear? Or did it not make a difference to your specific issue (maybe because the issue is not RF)?
If you have a diode rectifier or an internal SMPS that may explain rattle. Then a mains filter will not solve that as it is in the amplifier. Noise is something different just like hum.
If you have a diode rectifier or an internal SMPS that may explain rattle. Then a mains filter will not solve that as it is in the amplifier. Noise is something different just like hum.
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One way to find out is to record it with e.g. Audacity and run FFT analysis on it.
Just by ear.
I'll level with you, I'm more of a tinkerer than a full on diy'er. I have little knowledge of what goes on in the amp.
The noise is something similar to that what you used to get when a mobile phone rang anywhere near an fm radio.. (does that still happen lol)?
But much quieter, higher pitched and more random..
You can't hear it as soon as music is played, it really is quiet.
Thanks for the help anyway!
This thread is worthless without pictures, brand name & typenumber.
Yes FM and mobile phones are still around. The mobile phone is a good tool to check if an amplifier is RF proof.
Does the issue occur also without a source connected?
Yes FM and mobile phones are still around. The mobile phone is a good tool to check if an amplifier is RF proof.
Does the issue occur also without a source connected?
If you have access to each unit’s specs, one can choose higher amp unit with same attenuation curve; or simply look at inductance spec. Having said that, choosing 16A capacity with equivalent inducta nice and attenuation curve for 1 A load is overkill and a huge waste of $.
The help of AC power line filters will be situation specific. There needs to be a noise/interference in the frequency range of the filter, before it can do any filtering.
The differences will be in the Signal To Noise ratio. But it may be hard to measure after soldering in the filter, because there may be overlooked uncontrolled variables in the before & after setup.
The differences will be in the Signal To Noise ratio. But it may be hard to measure after soldering in the filter, because there may be overlooked uncontrolled variables in the before & after setup.
The line filter is for noise reduction in&out, mostly from switched PSUs- And since we all have some cheap wall warts hanging around, these filters are probably a must nowadays. Though I would consider them the first line of defense only, they are not a "magically-fix-it-all" component. But certainly a must, if you have a lot of line dirt from switches, starting motors (fridge) and so on, those voltage spikes are eliminated pretty well and could otherwise kill your own power supply. If you have audible differences in your HiFi component using such a filter, you have some serious line issues or your component is garbage.
OK let's forget for a while about mains filtering and focus on the issue Borats Baby is having. If Borats Baby is around to reply to questions that is.
There is (was) a known problem with the RIFA packaged mains filters which I believe has now been solved. They used to use a plastic case
that could crack over time and allow moisture into the case. As these were metallised paper the moisture would cause them to fail with
explosive results. Ive just replaced this type of capacitor in some QUAD products I recently bought namely a 306, a 34 preamp and an FM4 tuner.
All showed signs of cracking and one fell apart when I removed it.
that could crack over time and allow moisture into the case. As these were metallised paper the moisture would cause them to fail with
explosive results. Ive just replaced this type of capacitor in some QUAD products I recently bought namely a 306, a 34 preamp and an FM4 tuner.
All showed signs of cracking and one fell apart when I removed it.