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ISOTEK EVO3 Aquarius Power Conditioner Review

Rate this product:

  • 1. Poor (headless panther)

    Votes: 200 93.9%
  • 2. Not terrible (postman panther)

    Votes: 5 2.3%
  • 3. Fine (happy panther)

    Votes: 3 1.4%
  • 4. Great (golfing panther)

    Votes: 5 2.3%

  • Total voters
    213

solderdude

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the bit louder part is probably the 'better sounding' one.

Camera is moving around which doesn't help.
 

voodooless

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The funny thing is that in the original video, it appears as if there is a lot of difference and that it should be very obvious once you look at the data. But then if you put them next to each other, most of those differences fall away, and what is left is inconclusive at best.
 

solderdude

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The amplitude plots appear to show bigger differences than the generated numbers.
The fact that both parts recorded peaks of 0dB doesn't help.
Point is that it cannot serve as evidence. We also don't know what else happened (remote control volume difference for instance) in the time the power supply was changed.
Very dubious.
 

Mike82

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These tests of audio gear are interesting. Power conditioners continually get dumped upon and given some of the insane prices asked for these devices, the criticism is warranted. FWIW, I've been an audio hobbyist for 50 years, a reviewer for SoundStage! and an audio shop owner in the past.While I haven't heard the Aquarius, I have tried several PLCs over the past 20 years. Currently, I do not use any PLC- just my component plugged into a dedicated outlet. Some PLCs made small improvements, namely lower noise floor, and others had no effect.

One thing missing on almost all PLC reviews is a measurement of the noise on the on-sitmains being used in the review. I've heard obvious improvements in sound during demos at hotels (CES, RMAF), etc. I think the mains at those locations is quite noisy as can be measured with different meters, so sonic improvements seem reasonable. But in a private location with clean power? Probably little to no change.

One of the common objections Amir notes is that AC is converted to DC which should negate any affect a PLC might have and summarily reject any positive effect a PLC might offer. But questions arise: Does AC noise have any affect on DC ripple. If so, how much? Can reduction of AC noise affect the level of DC ripple that might be measured? At what point does DC ripple affect the sonics of a component? I might be convinced if Amir gave a base line measurement of AC noise at the test location as well opening and measuring any DC ripple in the component prior to, and after implementing the PLC. Even then I have to ask whether there is some, yet to be discovered, component to electrical theory that might help settle this debate.
 
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amirm

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One thing missing on almost all PLC reviews is a measurement of the noise on the on-sitmains being used in the review.
I measure this in every power line product I test including this one:

index.php


The floor of the spikes above is the relative noise floor. As you see, it doesn't filter anything until you get above audible band.
 
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amirm

amirm

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But questions arise: Does AC noise have any affect on DC ripple. If so, how much?
I have measured this in other reviews. Here, I show the electrical output of an audio device:

index.php


There simply is no impact on the noise floor of the FFT or distortions. So whatever noise there is on the power supply rail, it is not making it out of the device.
 

MacCali

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These tests of audio gear are interesting. Power conditioners continually get dumped upon and given some of the insane prices asked for these devices, the criticism is warranted. FWIW, I've been an audio hobbyist for 50 years, a reviewer for SoundStage! and an audio shop owner in the past.While I haven't heard the Aquarius, I have tried several PLCs over the past 20 years. Currently, I do not use any PLC- just my component plugged into a dedicated outlet. Some PLCs made small improvements, namely lower noise floor, and others had no effect.

One thing missing on almost all PLC reviews is a measurement of the noise on the on-sitmains being used in the review. I've heard obvious improvements in sound during demos at hotels (CES, RMAF), etc. I think the mains at those locations is quite noisy as can be measured with different meters, so sonic improvements seem reasonable. But in a private location with clean power? Probably little to no change.

One of the common objections Amir notes is that AC is converted to DC which should negate any affect a PLC might have and summarily reject any positive effect a PLC might offer. But questions arise: Does AC noise have any affect on DC ripple. If so, how much? Can reduction of AC noise affect the level of DC ripple that might be measured? At what point does DC ripple affect the sonics of a component? I might be convinced if Amir gave a base line measurement of AC noise at the test location as well opening and measuring any DC ripple in the component prior to, and after implementing the PLC. Even then I have to ask whether there is some, yet to be discovered, component to electrical theory that might help settle this debate.
If you watch his YouTube review, he has a machine which can actually produce a far more dirty AC power output than what is coming out of the walls.

He feeds this nasty signal into the components to see if the measurements will change and just compares to what comes out of the wall.

Nothing changes. The units themselves basically offer the same type PLC and probably cost the same as what it costs to implement it in a piece of equipment. Yet the industry charges 1000’s for this to be external.
 

milosz

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These tests of audio gear are interesting. Power conditioners continually get dumped upon and given some of the insane prices asked for these devices, the criticism is warranted. FWIW, I've been an audio hobbyist for 50 years, a reviewer for SoundStage! and an audio shop owner in the past.While I haven't heard the Aquarius, I have tried several PLCs over the past 20 years. Currently, I do not use any PLC- just my component plugged into a dedicated outlet. Some PLCs made small improvements, namely lower noise floor, and others had no effect.

One thing missing on almost all PLC reviews is a measurement of the noise on the on-sitmains being used in the review. I've heard obvious improvements in sound during demos at hotels (CES, RMAF), etc. I think the mains at those locations is quite noisy as can be measured with different meters, so sonic improvements seem reasonable. But in a private location with clean power? Probably little to no change.

One of the common objections Amir notes is that AC is converted to DC which should negate any affect a PLC might have and summarily reject any positive effect a PLC might offer. But questions arise: Does AC noise have any affect on DC ripple. If so, how much? Can reduction of AC noise affect the level of DC ripple that might be measured? At what point does DC ripple affect the sonics of a component? I might be convinced if Amir gave a base line measurement of AC noise at the test location as well opening and measuring any DC ripple in the component prior to, and after implementing the PLC. Even then I have to ask whether there is some, yet to be discovered, component to electrical theory that might help settle this debate.
>>I've heard obvious improvements in sound<<

Did you measure any difference? Listening doesn't provide objective information.
 

DonR

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Even then I have to ask whether there is some, yet to be discovered, component to electrical theory that might help settle this debate.
We can send men to the moon, sequence the human genome and harness the power of the atom but, you are right, there remain undiscovered "components" in electrical theory that cannot be measured and only the audio equipment manufacturers know about. :rolleyes:
 

MacCali

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Please consider, some people are new to this website. They may not be devoutly into measurements and could be skeptical. They are here interested to see results and learn.

It would be nice to keep responses on a professional or explanatory level. It’s just respect and courtesy, consider Amir’s response and mine.

In addition, it’s good to have more people partake in our community rather than scare them off and make them think this is how we function and want no part of it
 

solderdude

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Does AC noise have any affect on DC ripple.

Not really on the DC ripple. You would have to understand that only near the 'tops' of the mains sine the rectifiers act as a 'switch' with a low (but not 0 ohm) switch that passes through a current that momentarily charges smoothing capacitors. These generally are large in capacitance.
The rest of the time the output voltage of a mains transformer is literally disconnected from the DC rail (the voltage across the smoothing caps).

3300uf-1n4001-33ohm.png


The above circuit is creating 9Vdc with a constant load of 0.3A (2.7W)
As you can see the DC voltage is only 'charging' the reservoir caps during 8ms and not in a 'switch' like manner. It has a series resistance (the transformer itself + dynamic resistance) For lower power devices the dynamic resistance of the diode can be in the range of several ohm near the highest peak current.

This is an important aspect.

So only current flows into the smoothing capacitors at intervals and that current is not 'switched' but more like a resistor that varies in value between (almost) infinite to a few ohm at a short moment.

For high powered speaker amp power supplies, when drawing lots of power, that diode resistance is below 1ohm though but not at 'normal levels' and certainly not for devices like DACs, pre-amps, CDP etc.

If so, how much?

Well this depends on the frequency of the 'noise', dynamic resistance of the diode, and value of the smoothing capacitor.

There is always a ripple of the DC. It takes time to charge the capacitor. At 100Hz the 'resistance' of a 2200uF smoothing cap is around 0.7ohm.
There is a series resistance of a few ohm (the diode + secondary winding + transformer losses) charging the capacitor at short moments where the lowest resistance of the diode 'switch' is very short.

Now lets calculate the resistance of the 2200uF cap at an audible 1kHz... 0.07ohm.
At 10kHz it is a few milli ohm.
This means that only at very short intervals (when the charging current is maximum) there can be noise currents charging the cap. As shown the 'resistance' of the smoothing cap for higher frequencies is very, very low while the resistance of the current feed (the diode + secondary winding + transformer losses) is relatively hundreds of times bigger.
It basically forms a low-pass filter (20dB/decade) of somewhere between 150 and 500Hz.

So at the short moment the capacitor is charged with a current there might be some 'extra' current (higher frequencies) that may charge the smoothing caps a fraction higher due to the presence of a tiny bit if extra current. That high frequency thus is greatly attenuated by the low resistance of the smoothing cap (at that frequency) and the relatively high resistance of the charging circuit ((the diode + secondary winding + transformer losses).
The 'attenuation' at 1kHz will be about -40dB and at 10kHz about -60dB.

Add to that only a low level of noise will be present. For arguments sake lets assume noise on Amirs mains is typical for domestic situations. This is down about 50dB opposite the mains voltage. At the output of a mains transformer the spectrum up to 10kHz will be about the same.
index.php

Now lets assume assume 'noise' is 10 times higher so +20dB.
In noisy environments at 10kHz the noise may well be -50dB down instead of around -70dB.

This means that opposite 9V the level of the incoming AC at 10kHz is -50dB and attenuation (due to RC attenuation at those frequencies) is approx. 60dB as well.
So ONLY at short intervals (during the peak of charging the reservoir caps) a 10kHz 'noise' current is -110dB lower than the AC input.
At 9V the AC input is around 6.5V so about 20uV extra AC charging current will be present.

Then we also have the PSSR (PSRR) of the circuit which can be between - a few dB (poor circuit design) down to -60dB or so.
So 'noise' (only present during charging and NOT the entire time) could be -120 to - 190dB opposite the audio from the circuit.
The noise floor of electronics is much higher by itself so any 'noise' at higher frequencies is greatly attenuated by the rectification of AC.

Its why, when looking at audio gear with a poor power supply and PSRR, we only see some mains harmonics up to a few kHz at most at inaudible levels and no HF noise.
Can reduction of AC noise affect the level of DC ripple that might be measured?

As you can see in the spectrum above mains (because of it being flat-topped by thousands of connected rectifiers on the mains) can have a spectrum up to a few kHz at most but at very low levels compared to the mains frequency.
Mains filters cannot lower those harmonics. They can only lower frequencies well above a few kHz at best.
Only a true regenerative power supply can do that and even those are not perfect but can have 20 to 30dB lower harmonics and noise.

So a mains filter will do NOTHING at audible frequencies only higher up (see attenuation of the blue frequencies which are already 90dB down by themselves.

At what point does DC ripple affect the sonics of a component? I

That would depend on whether or not the audible threshold is reached so depends on the efficiency of the used transducers (speakers/headphones) and listening distance.

Ripple will be mostly 100(or 120Hz) and its harmonics up to a few kHz at most, not 'noise' on the mains.
Poor ripple rejection will result in a constant audible hum, which may even have a 'sharper' sound.

Common mode crap is the enemy in audio.

Now the biggest 'problems' in audio do not come through the DC ripple (we have seen that this is not the issue).
It comes from common mode currents (which can cut through DC like butter) and ground loops.
These are AC currents entering into the audio path and creating audible gremlins of all sorts and types.
This can 'ride' along on mains and sometime enter the audio path with very little attenuation.

This, however, alongside with ground loops is a totally different can-o-worms which can be reduced by filters (but only above several kHz) and by regenerative power supplies.

The real solution, in many cases, would be to break the ground loops where they occur and or buy well designed (not expensive) cables or equipment that doesn't have a poor PCB/wiring layout inside that may make this aspect worse.
 
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sarumbear

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Does AC noise have any affect on DC ripple. If so, how much? Can reduction of AC noise affect the level of DC ripple that might be measured? At what point does DC ripple affect the sonics of a component?
I think if you learn how AC to DC conversion works you will realise that capacitors are there for the exact reason you are enquiring for.
 

JamesRF

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Over the years I've listened to a number of power 'conditioners' at home, at the urging of local retailers. In my experience they make no difference at all, or actually increase noise. In my experience, where they're not simply glorified power strips, they are effectively big amps that can generate audible hum! The claims made for 'devices' to 'clean' AC are in my view among the most outrageous made in the hi-fi world.
 

Mike82

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I think if you learn how AC to DC conversion works you will realise that capacitors are there for the exact reason you are enquiring for.
I understand how the conversion works. I am a former low voltage electronics technician. My question however pertains to how much ripple can the capacitors remove, e.g., if the degree of ripple exceeds the capacitors' ability for smoothing the ripple, then how might the sonics be affected? Second- Does the level of noise on the mains contribute to the potential level of ripple. I'm no big proponent of PLCs. Also, Would you please comment on this 2 minute video.
 

Mike82

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We can send men to the moon, sequence the human genome and harness the power of the atom but, you are right, there remain undiscovered "components" in electrical theory that cannot be measured and only the audio equipment manufacturers know about. :rolleyes:
Read up about Dr Semmelweis and his challenging current science before making a fool of yourself. 100 years ago, experts like yourself would have laughed at one who proposed the concept of DNA having a factor in epidemiology, so :rolleyes: yourself.
 
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solderdude

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I am a former low voltage electronics technician.

Why not measure it yourself in that case that should not be that difficult to do ?
You could build the 'noise sniffer' and listen to the DC rails while connecting say a power drill to the same mains socket as the audio gear or some cheap Chinese LED lights ?
 
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solderdude

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Would you please comment on this 2 minute video

1: It is an advertisement for Shunyata
2: Measuring small signals on a body also includes ground and this can cause substantial error signals that have to be dealt with.
3: I am quite certain the issue in the measurements here are NOT coming from lowering 'noise' on internal DC power rails in the sensitive equipment.
 

Mike82

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1: It is an advertisement for Shunyata
2: Measuring small signals on a body also includes ground and this can cause substantial error signals that have to be dealt with.
3: I am quite certain the issue in the measurements here are NOT coming from lowering 'noise' on internal DC power rails in the sensitive equipment.
So, regarding point 2: Am I to assume that the physician running the electrocardiac lab did not know how to do perform these studies until the Shunyata folks showed up? Really???

Then, what do you attribute the change in measurement clarity other than the device? Point 2 cannot be taken seriously.
 
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