NordOst QRT (Qk1 and Qv2)
Contents
NordOst, of course, we know from cabling. But they have also been making other accessories for years. Including these plugs. The QK1 is a different type of plug than the Qv2. This is also reflected in the prices. The Qk1 costs 275 euros, the Qv2 costs 399 euros.
That an price says nothing is evident again. The Qk1 ‘wins’ hands down in our blind test. Really in all areas. Together with the Isotek, the Qk1 is the favorite. More flow, more quietness, more calmness and in the case of the Qk1 also a nicer stereo image. “You feel the bass. They go very deep”. “Light-footed” and “that’s how it should be!
Without question, the Qv2 also has an audible effect, but your “testers” just disagree. Martijn doesn’t like it at all. An since Martijn is “leading” in the listening test, his vote wins. “Bit flat and dull”, “Great dynamics, but violin is not that rich”. And, “takes away from the richness of sound”.
LCR Measurements NordOst QRT (Qk1 and Qv2)
Response and noise measurements NordOst QRT QK1 and QV2
Unfortunately, NordOst’s website is peppered with marketing talk:
Using our MMF technology in a loading application prevents time delay and distortion of the transmitted signal, making the AC current that much closer to the desired “distortionless condition”.
Both filters do nothing in terms of filtering. In short: that is simply not true. That it does something is clear, but it does not directly lower the noise floor. At least not in our measurements. We do measure a circuit or something (we cannot open the plugs; they are glued shut, or locked in some way). This circuit is visible in the last measurement: there you can see a big sway in the response. But check the scale. It’s only 1.4 dB. That’s very little. A filter achieves -30 or -40 dB easily.
Overall NordOst Qv2
| Auditory | Measurement |
| Without a doubt affects playback. We disagree on whether it is good or not. | Not able to see clear operation. But we are measuring a circuit. |
Overall NordOst Qk1
| Auditory | Measured |
| Very fine influence. Very smooth and rhythmic character with more quietness overall. | Not able to see a clear effect. But we are measuring a circuit. |
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.