Pros: EASY to Use (Just plug it into your USB audio chain directly before your DAC). It "Just Works"! Nothing to tweak...
Part 1 - TORTURE TEST
So, have you ever heard the noise from an old laptop's hard drive spinning-up, or the electronic "chirp" of your mouse cursor moving across your screen during music playback?? Chances are that if you're using a half-way decent PC/MAC from last 10 years or so, that you haven't. But hey, I figured why not REALLY test what this device can do? Where's the challenge in cleaning-up already clean, modern USB 3.0 connections? (SPOILER! By the way, it made my modern USB 2.0 & 3.0 signals sound incredibly clear.) So the performance torture test was devised. I grabbed our old HP and DELL laptops from the basement Pentium (Yes, PLAIN INTEL single core PENTIUM CPUs) PC archives (Read as spare parts rack) and coaxed them back to life running old versions of Windows XP & using Windows media player or FOOBAR 2000 and played old 16-bit sampled mp3 files. Did it magically make this old equipment and poorly sampled, high-loss audio files sound like high-end audiophile-worthy output? NO. But what it DID do to my surprise is reduce the harsh, "ringing" (The only way I can describe the distortion/aliasing from the mp3 files) and virtually eliminated the noise from the poorly-shielded components in both laptops. No screeches or squawks randomly intruding on the playback once the iPurifier 2 was in the audio chain. Unfortunately, DSD files were a bit too much for these old laptops, but they DID manage to do justice with some of my lower-sampled FLAC files, and actually managed to make them sound GOOD! (CPU run-time was maxxed-out, and nothing else could be done on the PC at the same time while the files were playing back though.) All in all, a VERY impressive result. :-)
Part 2 - THE ACTUAL REVIEW
I evaluated the iFi iPurifier 2 with the following equipment:
SOURCE - Dell XPS 8500, Dell Inspiron 530 (Both running Windows 10 PRO 64-bit)
DAC - iFi iDSD (DAC) FIIO e17 (DAC) ONKYO TX-NR636 (DAC) iBASSO DX90 (DAC)
AMP - iFi iDSD, iFi iCAN, iFi iCAN SE, Schiit Audio ASGARD 2, & ONKYO TX-NR636
HeadPhones - Beyerdynamic T1 (ver.2), HifiMan HE400i, Sennheiser HD-650, HD-800
Player Suite - Foobar 2000, & JRiver Mediacenter 21
Now I'm not going to throw a bunch of specs at you as they are all over the web and in other reviews, so I will keep this to "what I experienced personally":
When I listen to music over my DLNA server, I am just listening passively. When I go directly from my media PCs using FOOBAR or MediaCenter 21, I am usually actively listening, and looking to lose myself in the audio. The iPurifier 2 is best enjoyed by me during the latter setting. To be honest, my configuration already sounded pretty good to me as it was. I never was wanting for clearer signal, or more refined detail. I knew it was out there, but I figured that the pursuit of it would be so cost-prohibitive, that it really wasn't something that I couldn't live without. (Incorrect assumption #1)
So when I was sent the iPurifier 2 to try out with my audio gear, I was kind of skeptical to be honest. I mean, USB filtering? How much of a difference can THAT make? (Incorrect assumption #2)
First, this piece of kit does a good shade more than "just filter"; It re-clocks, conditions, boosts, & noise cancels. All seamlessly, with NO drivers or configurations needed. It is literally "plug-n-play", and how often does something THAT simple happen nowadays?
So what did I hear?
- In my mp3 low-res files, it softened the "edge" of some of my harsher low-quality 16-bit recordings. (Think old Bruce Springsteen and George Thorogood live performances that sound almost 8-bit... But are SO fun to listen to!)
- In my basic 14.4 FLAC files, it brought-out more of the layers in instrumentals. (There are sub-riffs in Pink Floyds' "Learning To Fly" & "Money" that I never heard quite so prominently. before.)
- In my Hi-res FLAC rips from CD there was just more "oomf" and weight to song from The Moody Blues, Alan Parson Project (YOU MUST hear "La Sagrada Familia" with the iPurifier 2 enhancing!)
- In my DSD 2.8MHz & 5.6MHz files the improvements were bother more difficult to catch, yet more impactful at the same time. There was less to correct, but what WAS corrected just stood out all the more. Holst, Wagner, Clapton, Michael Jackson, Billy Joel, Toshiro Masuda, Kitaro, it all just took me 10s of hours to get past trying to listen the subtle nuances that I had never heard before and truly enjoy!
So what's the point?
For me, the iPurifier 2 represents if nothing else, the single SIMPLEST way to enhance all of your audio collection in one fell swoop. Will it be as dramatic an upgrade as upgrading from a sub-$100 "generic" DAC to a higher-end iDSD Micro, Chord Hugo/Mojo or better? Probably not. But there is simply no other addition to your audio chain that you can simply "plug-in", and not even have to power it on, that will have as much impact on your audio as the iPurifier 2 that I have ever heard of.