I meant micro vibrations adversely affecting the performance of the electronic components.
On hi cap I have if dc blocker, on 250 dr dc blocker +
Do you think ifi dc blocker is enough for hi cap dr and ifi dc blocker plus is enough for nap 250 dr? Thanks
Sorry I donât know⌠I am sure if you suffer from buzzing transformers they will help there, but you need to decide if you prefer the end result or not.
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I had two IFI DC Blockers. One on each of my NAP 250s with no problems.
Did the job nicely.
DGâŚ
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I prefer my power supply without dc-blocker.
Letâs not forget that if a toroidal hums due to saturation then other issues are present too. Toroidal transformers are a bit Jekyl and Hyde in this respect. They are often chosen over EI core for the low EM radiation the keeps flux confined to the core and reduces the need for shielding. But this is under optimum conditions. When a toroidal core saturates, they then tend to produce far more EM radiation than an EI core in the same circumstances (which are fairly consistent given good or bad conditions). So that humming is more than just a nuisance. Now you potentially have a large unshielded buzzing beast bathing delicate circuits in itâs unconfined EM flux field.
This dual nature of toroidals is a reason some high end manufacturers still opt for EI core. They can be more consistent.
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Indeed, hence my post earlier, when a high efficiency transformer saturates it produces distortion and relatively high frequency harmonics into the windings, not least the secondary windings, which the power supply has to work harder at attempting to remove, itâs kind of like adding a noisy device onto the mains.
Of course the higher efficiency does mean better load regulation can be achieved for a particular size transformer, but at a cost.
However soft humming is normal⌠itâs the strong rasping humming that typically varies is often a sign of a saturating transformer.
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I have to admit, Iâve personally never had a problem with a single transformer humming (pressing ear to the case doesnât count) in the UK, US, Belgium, Hong Kong or Japan. And the few years I spent in hifi retail I saw a lot of problems but customers mentioning humming wasnât one of them.
About two uears ago I bought the Ifi DC Blocker to satisfy curiosity. At the time I had a 0.03 offset and wanted to hook the DC blocker up to the scope and see if it measurably worked. It certainly wasnât enough to cause my gear problems. I never got round to it. I still have it somewhere. But I have no measurable offset in the new house. So both it and the isolating probes are gathering dust.
And indeed why other high end manufacturers opt for high frequency switch mode power supplies, as they can side step some of these issues⌠I guess everything has to be a compromise sooner later.
I found previously my NAP250 used to suffer occasionally from a noticeable rasping hum⌠it used to come in wave type effects⌠my 552 PS didnât seem to suffer to the same extent, and not a peep out of my ndx2 or Nait50
Hi, my overall feeling after several tests is that without both ifi dc blocker sound is more bold, more full. This is clear when there is silence and attention is fully dedicated to listening, therefore I will take away the blockers when I am home alone and have time to listen, unfortunately quite rarely, rest of the times I will keep them and enjoy the silence of transformers
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