General Information
Let no noise go unsilenced
If you think of mains power as the ‘gasoline’ fuelling your audio system, the AC iPurifier is the product that ensures that it’s getting a clean, super premium blend to deliver the best possible audio fidelity.
The AC iPurifier is the latest in iFi audio’s stable of ‘power products’ designed to clean-up noisy mains supplies to audio systems. But this is no ordinary mains purifier. Technologically advanced, it’s Active Noise Cancellation (ANC) circuitry can eliminate far more noise across the frequency range than other passive devices. At -40dB, the difference is as distinct as night and day.
Specifications:
- Noise Reduction: >40dB (> 100x)
- Surge Protection: max. 30,000A @ 1,000V/10uS
- Operating Voltage: 90V – 265V
- Size/Weight:
(USA) 40mm x 105mm (L)
108 (g) / 0.24 (lbs)
(EU) 40mm x 115mm (L)
126 (g) / 0.28 (lbs)
First, we need to assure everyone that no snakes were hurt in the making of the iPurifier AC and no snake oil is contained in the product, the only oil in the production chain is crude oil that provides the basics for the plastics used.
Is there a scientific basis for the function of the device? Certainly and we can measure significant attenuation of noise on our 2.5GHz RF spectrum analyser between the AC iPurifier inserted and removed.
Indeed using additional plug in capacitors to filter HF noise is not exactly new and tends to be fairly effective at higher radio frequencies. However both practicality and safety agency requirements mean the values of these capacitors have to be fairly low and their effect is thus limited to higher frequencies, often > 1MHz.
In modern EMC (electro-magnetic compatibility) testing, typically frequencies below 150kHz are not included and frequencies below 500kHz allow relaxed levels of noise emission.
So many power supplies (even linear ones) release fairly large levels of noise in these frequency bands while passing all EMC standards. And it is often these lower RF noise components that cause trouble in audio systems and that are not easily filtered inside of audio gear either (no matter how diligent the designer is).
Going active allows us to address especially this < 500kHz noise rather effectively. This way the AC iPurifier achieves very wide bandwidth compared to simple passive capacitor based plug in devices.
Our ANC uses a simple analogue forward circuit, which is very fast and is backed by and hands over to capacitor based passive filtering for high frequencies. So there is no "noise echo" or any such problem.
Where the active circuit is fast enough to provide the opposing noise it kills noise, where it becomes too slow passive filtering through capacitors takes over.
The use of active noise suppression in mains powered systems is not exactly new, it has been used in large scale industrial applications for a while. It's application in domestic power systems to reduce mains born noise at frequencies much lower than possible using passive means and specifically to improve audio systems.
A note on the surge suppressor. These devices are in parallel with the mains, they are not resettable circuit breakers - instead their function is to limit any voltage between live/neutral by drawing extra current.
This current drawn to limit the voltage to safe levels may very well trip conventional current based circuit breakers, but the MOV is NOT a circuit breaker in itself. It also needs no re-set, if the surge is over it simply stops drawing current to limit the voltage.
Mains is the fuel that powers an audio system. Whether it is clean or not has a material impact upon quality and the user’s enjoyment of playback. iFi’s latest ‘power product’, the AC iPurifier, is no ordinary mains purification commodity.
Technologically advanced, it is an ACTIVE not a passive product, so it goes above and beyond and cancels far more noise across the frequency range than passive devices.
It is effective against both:
- Common mode noise existing equally on both of the power pins, referenced to the earth pin.
- Differential noise existing only between the two power pins – the net to earth is zero.
Nullifies noise others can’t reach
Compared to other generic noise filters, the AC iPurifier is superior because it is ACTIVE as opposed to passive. This enables it to achieve a far more comprehensive termination of noise across the frequency spectrum. As noise exists across the frequency range, this clearly means the AC iPurifier is unparalleled when it comes to neutralizing noise.
This chart compares the AC iPurifier (green line) which is ACTIVE to generic mains filters (red line) which are typically passive.
The effective noise reduction difference is as different as night and day.
- MUCH better at up to -40dB and…
- Effective across a wide frequency range, compared to passive filters which cover only very high RF frequencies.
The AC iPurifier is designed for use in ANY mains powered audio system and is very effective when added to modern audio systems that have an abundance of digital and analogue components. Typically these systems are powered from a plethora of mains plugs. All of these ‘wall warts’ can add their own unwanted noise issues and pollute the local mains supply. However, the design of the AC iPurifier is such that it is even more effective if several are used to ‘contain’ the same type of noisy sources.
Insert it into the AC mains wall outlet supplying the audio system OR insert into the mains extension block powering the audio system. Try both locations to determine which has the greatest impact on improving any noise issues.
Bristling with serious Power Technology
Compared to similar AC power products, the AC iPurifier can boast the technological features below, making it far more comprehensive and effective than its rivals.
Not only does the AC iPurifier carry out exceptional noise filtration, it also has several other features to go that extra mile:
- Smart Diagnostics of Polarity – with both versions, EU and USA, it is possible to connect in the opposite polarity. The AC iPurifier detects a change and indicates this.
- Smart Diagnostics of Earth – detects if the audio mains system it is inserted into has a Ground/Earth or not.
- Intelligent Ground – by attaching the optional ground cable, it is possible to give any system an audio ground. Going directly to the AC iPurifier and into the mains, the Ground/Earth will be of the highest quality connection, making it the most effective at draining system noise.
- Overvoltage Protection System means that electrical shorts, lightning strikes and surges in the mains will be detected and the AC iPurifier will clamp the voltage to safe levels to protect your AV components from damage.
- The AC iPurifier is no ordinary mains filter.
- Firstly, and most importantly, it purges the audio system mains of noise using both Active and Passive technologies to work across a wide frequency spectrum.
- Secondly, it provides an intelligent Ground/Earth to reduce noise for cases of a “missing earth” causing problems with noise.
- Thirdly, it checks and detects the local mains for Earth and Polarity anomalies.
- There is simply no other mains power improvement accessory like it.
