Overall measurements
Contents
Filterslopes – overview
We have overlaid some graphs here for you. That way you can see how they compare – measurement-wise. It’s funny to see that the ‘conventional’ filters have a clear roll-off and thus have a ‘filtering’ effect, that the two ‘coil’ filters and the Akiko really do nothing in the filter tests and the ‘active’ models do show some craziness in the measurements. So there must be something going on there. And that’s what we hear.
Bottom line?
This is and always will be complex stuff. Even these small plug-in filters. Some have circuitry, some are passively designed and some have a “voodoo” effect with crystals, coils or other fuzzies. In the case of the latter category, we looked at the claims on the website to determine if they were true. In many cases, unfortunately, they are not. That can be called misleading. If you claim to lower a noise floor it should be measurable. It isn’t. At least not up to 35 MHz in our case. Then we may conclude that it does not lower the noise floor.
In the case of the active plugs, we may have to find another approach. The question is how. If you have any ideas; feel free to post them below this article!
The listening test proved to be particularly interesting, because they do partly correspond to measurements. All filters with a proven filtering effect show a clear effect. So do the filters with active approaches… although we still have difficulty measuring that.
The two plugs with coils show very little…. which your author did expect after the measurements. The Akiko is the odd one out…. which seemed to do something… although it was very subtle…
These filters are often marketed as being used in a wall AC mains socket adjacent/next to another mains socket into which a power conditioner plugged (ie both AC mains sockets next to each other /side by side are on the same mains circuit).
This is different to your test set up. So my question is…..(given the way these filters are marketed/manufacturer’s recommended use)…. can a power conditioner actually benefit from having a plug in filter along side it on the same AC mains circuit?
I think your test answered the question of the differences between using a power condition (the Aquarius) and a plug in filter….but not the impact of using both together in parallel.
Great stuff as usual in your testing/reviews. Unlike other youtube channels, which shall remain nameless…no egos, no hidden agenda, no human insecurities that require reductionist scientific measurements/calculations to explain the unexplainable (ie you are comfortable within yourselves and have the wisdom to accept what cannot be explained)…your passion is genuine and all purely in service of the music/hobby. Because of your holistic and much more balance and fluidly intelligent approach, i have stopped watching these other channels. Keep up the great work. (Btw a quote which i love and is very apt….”the mind (and by extension one’s ears) is/are like a parachute. They only work when they are open.”😉🙈
Thanks Alexander! Appreciate your feedback!
If you have a decent conditioner, I cannot imagine a parallel filter has much impact. The Aquarius for example already has parallel filters build in. You can use them together, but I never heard a significant difference. I would rather buy a decent power cord. :-).
Thanks Jaap. That makes sense. And yes it is my experience too that power cords can make a signifcant difference and are worth investing in ahead of many other things. Cheers.
Hello Alexander. Thank you for your kind words. Good to read that our intentions in how to test come across.
Parallel filters are often recommended to plug into the wall socket next to a power strip, which is logical. It very much depends on the power conditioner used if this is a wise idea. A lot of conditioners filter, which means that you are stacking filters. As with anything in electrical connections and HiFi, stacking stuff can have an effect which a particular listener very much enjoys, but it is a bit of a hit or miss. Or a very dangerous HiFi rabbit hole where hobbyist really get lost and are getting further and further from what they are looking for.
Thanks Martijn. Yes you are right in terms of marketing being more about being placed in paralell with power strips. Also very wise words about hit/miss &/or rabbit holes….both of which proven to be expensive for me in the past… so always nice to be reminded! Thank you😀
Good job and well done!
Would there be similar blind tests for USB/RCA type noise absorbers such as YUKIMU USB noise absorber PNA-USB01 and The Chord Company GroundARAY in the coming future? thank you.
We can check that out in the future… sure!
Good job and well done!
Would there be similar blind tests for USB/RCA type noise absorbers such as YUKIMU USB noise absorber PNA-USB01 and The Chord Company GroundARAY in the coming future? thank you.
We can check that out in the future… sure!
https://www.audiosciencereview.com/forum/index.php?threads/isotek-evo3-aquarius-power-conditioner-review.30223/post-1324437
[ I have only listen to one audio that I know very well, Jacques Loussier – Little Fuge in G Minor.
Conclusion: it sounds worse with any filter. Dynamic is lost.]
I didn’t notice any loss in dynamisch. These are parallel filters… With serial filters: yes… definately.
https://www.audiosciencereview.com/forum/index.php?threads/isotek-evo3-aquarius-power-conditioner-review.30223/post-1324437
[ I have only listen to one audio that I know very well, Jacques Loussier – Little Fuge in G Minor.
Conclusion: it sounds worse with any filter. Dynamic is lost.]
I didn’t notice any loss in dynamisch. These are parallel filters… With serial filters: yes… definately.