Pros:  improved depth, blacker background, crisper highs, more refined overall sound, small, flexible voltage/amperage/wattage (works with most DC wall wart type sources), great set of adaptors, inexpensive

Cons: improvements are small (can’t rule out placebo effect), effect will depend on system quality (more noticeable with better headphone), will be more cost-effective improvements for many, attracts ridicule like a Kanye West monologue

List Price: $149

Product Website: https://ifi-audio.com/products/dc-ipurifier2/

Rating Disclaimer: ratings are subjective. Audio quality and value do not mean the same thing across all prices. A headphone with a 5 rating on audio at $5 does not have equivalent sound quality as a 5 rating at $500. Likewise, value at $5 is not the same as value at $5000 dollars.

Introduction

Alright. I’ll admit it. I’m basically officially an iFi fanboy and ‘snake oil’ believer. So if you have a problem with my appreciation of iFi’s spartan but well made and excellent sounding gear, you can find the exit at the top of your browser. If you have a problem with people believing that power/USB/unobtainium wires might make a difference, then this review isn’t for you. Because of my caution when looking at power products and wires, I don’t tend to make any sweeping pronouncements. Differences are rarely night and day (not impossible, but rare).

If you want to see my previous reviews of iFi gear you can find them here:

• iFi iDAC2 (4.16 rating)
• iFi iPurifier2 (4.5 rating)
• iFi iCAN SE (4.16 rating)
• iFi Micro iDSD Black Label (4.89 rating)
• iFi Nano iDSD Black Label (4.76 rating)
• iFi iEMatch2.5 (4.83 rating)

I’ve also reviewed the iFi Micro iUSB3.0, but that was one of my first reviews and was effected by noob-thusiasm to some degree, which is why I didn’t migrate it over here. You grow and learn as a reviewer, but I don’t think anyone should try to erase their youthful exuberances or oversteps.

Lawrance at iFi asked me if I wanted to review this and I told him I had asked about the original DC iPurifier after hearing that it helped with the LH Labs Geek Pulse X-Infinity on a Japanese blog—I don’t read Japanese, but Google translate is less hopeless than it used to be. I still don’t have any other sources that this would make sense with, so the X-Infinity is our test subject in this review.

Usability: Form & Function

The box that the iFi DC iPurifier2 comes in is iFi’s standard small item box. They use the same box for their standard iPurifier series and the iEMatch few. I have to imagine they use it for their Defender and other USB paraphernalia. Inside the box are the DC iPurifier2 (in white, looks and feels sturdy) and a bunch of convertors and an extender. For my purpose, the extender is where it’s at. It gives me some distance to safely switch the DC iPurifier2 in and out of my power chain for quick comparisons. The set of adapters should allow this to be easily used for most folks. The fact that it takes a large range of inputs further enhances the usability. Sweet. Gotta make sure your users are happy.

Audio Quality

This is where people will say I’m nuts, or not. Power clean-up gear is usually met with suspicion at best and hostility and rage at worst. The worst outcome is more common. People are afraid of ‘the other’ and power and interconnects might as well be strange accented blob-entities serving up spiced mystery meat from Betelgeuse IV. Whenever I talk about wires, I know I’m going to get some folks who call me a charlatan. Comes with the territory, I guess.

Signal Chain: Dell Inspiron 5000 Series Inspiron 13—Vertere Acoustics Double DFi USB—iFi Micro iUSB3.0—LH Labs Lightspeed 2.0 USB Cable—LH Labs Geek Pulse X-Infinity—WyWires Red balanced (4-pin XLR) headphone cable—Sennheiser HD600 (tights mod)

Power Chain: LH Labs Geek Pulse X-Infinity—iFi DC iPurifier2—stock wall wart—Weiduka AC8.8 Filter/Protection—3m MCRU No. 11 UK Mains Cable—normal wall socket

Tracks: Beck – The Horrible Fanfare/Landslide/Exoskeleton, Animals As Leaders – Ka$kade, Metallica – Until It Sleeps,

I tried to do the test with speakers, but the switch time was absolutely unacceptable for being able to pick out any subtle differences. So I disconnected my X-Infinity (brilliant DAC for speakers, huge soundstage and great resolution), and put it into a headphone set-up at my reviewing desk. In this situation I was able to use the extender dongle to connect and disconnect the power without having to reach around the back of the LH Labs X-Infinity, which meant that I could do switches in about 12-30 seconds by turning the volume all the way down (X-Infinity has no spike protection), disconnecting the Sennheisers, powering off, removing or adding the DC iPurifier2 and then reversing. Ideally, I’d have 2 identical set-ups for faster switching, but I’m no rich boy.

The general effect is a bit more stage depth and a blacker background. The blacker background allows more resolution for instruments within the stage. High notes also seem to be sharpened, which may or may not be a positive. The DAC/Amp I used it with, the LH Labs X-Infinity, can be on the bright side, so it can get a little more fatiguing. Enhanced highs could also be the reason for more stage depth, and enhanced resolution. I’m also getting a touch more sweetness and airiness on Beck – The Horrible Fanfare… when the female vocals feature at about 5:30 seconds into the song. It’s nice. This is a power component, so there is no way that DSP is being applied to the sound. Placebo, maybe, but DSP, no way!

On most tracks percussion instruments are given a bit more separation in the stage. Treble is just a bit more refined. Comparatively, the sans DC iPurifier2 setup sounds a touch hazy.

The X-Infinity is not known for being an exceptional headphone amplifier, so there are limits to what can be expected in terms of sonic improvement.

I decided that I’d see how the setup did with a bit more of a challenge, so I hooked up the HiFiMAN HE-1000 v2 and adjusted the volume to taste (-14.0dB according to the readout). I played it loud, fast and hard, Judas Priest – Breakin’ the Law. Breaking the laws of physics, apparently! As if physics are perfectly understood.

New signal chain: Dell Inspiron 5000 Series Inspiron 13—Vertere Acoustics Double DFi USB—iFi Micro iUSB3.0—LH Labs Lightspeed 2.0 USB Cable—LH Labs Geek Pulse X-Infinity—Atlas Zeno headphone cable (4-pin XLR balanced)—HiFiMAN HE-1000 v2.

When I take away the DC iPurifier2, Rob Halford really does sound out of work and down, comparatively. He sounds restrained. He needs some action in his life. Here, Rob, have a DC iPurifier2.

On Marvin Gaye – What’s Going On the bass is deeper back in the stage, with greater texture. The male backing vocals are a bit clearer with more definition, it’s like a fog has been lifted. The stage depth is reduced without the DC iPurifier2, which actually makes the setup without DC iPurifier sound a little louder—things sound louder if they are closer to you. The edges of notes sound a bit softer when I take away the DC iPurifier2.

Damn it, Stevie, I think I’m in trouble. A power management device seems to be improving the sound. How? Am I Too High? Nah, cymbal decay is slower and less realistic when I pull out the DC iPurifier2 from the power chain. I’m also getting a shallower sound with a warmer tinge when examining Stevie Wonder’s Innervisions.

Specifications

Specifications
Price	$149
DC range	5-24 volt DC power supply (up to 3.5A, 84W)
Chassis	iFi ‘Final’ aircraft grade RFI and EMI shielded aluminum
Adaptors	5.5 x 2.1mm extension, 5.5 x 2.5mm, 3.5 x 1.35mm, polarity invertor
Dimensions	Body: 55mm (L) x 19mm x 19.5mm (D)
Warranty	12 months

Acknowledgment

The iFi DC iPurifier2 was supplied free of charge by iFi USA for the purpose of this review. I don’t own it, but I haven’t been instructed to return it.  I have not been compensated for this review. The views expressed are my own—warts and all.

Conclusions

It makes a difference. The difference was more apparent when I combined it with USB clean-up and moved up to the more resolving HiFiMAN HE-1000 v2 instead of the Sennheiser HD-600. The difference wasn’t transformative. I enjoyed myself with and without the DC iPurifier2, but more with it. My findings, if you can call them that, may not be generalisable to every setup, as I had a pretty clean signal chain already with good power management and cabling.

I marked down the value here because I don’t think this will benefit every system in a noticeable way. If you are rocking low resolution and high distortion from your headphones, this isn’t going to do a darn thing. So the advice from me is to upgrade your headphones and then see what tweaks like this can do. The DC iPurifier2 will work with small equipment, but it won’t do anything for a big AC plug, and unfortunately I don’t have a linear power supply to test it against. I can say that it is definitely smaller than a linear power supply. This thing fits in your pocket and is effective. Is it better than other things that fit in your pocket and are effective? Well, that depends on your particular thrust in life and your existing endowment of toys outside your pocket.

I can recommend it.