iFi Micro iTube2 Intro iFi is a brand born from trickle-down technology, licensed from AMR with one simple mission: To provide the absolute best quality ‘Bit-Perfect’ audio from computer generated sources . All iFi products proudly boast clean Class A analogue circuitry with absolutely no digital signal processing; The signal stays true to the source throughout! Since iFi broke into the scene in 2012 they have been making huge waves in the audiophile community, offering products who’s performance is on par with their beautiful, modular design! Every product has been carefully engineered for perfect symmetry and synergy with one another, allowing the user to custom tailor their stacks to their desired needs. As part of the original micro line, the micro iTube was an incredibly popular product. Described as the ‘Swiss Army Knife’ of components, the original micro iTube boasted a tube buffer (0dB or 6dB gain), pre-amp with analogue volume control (0dB or 6dB gain), 3D enhancement effects for speakers, as well as ‘Digital Antidote Plus’, a feature designed to take the “digital’ out of the source and make it sound more ‘analogue’. For many, the sleek and sexy multi-functional micro iTube was hailed as something they never knew they wanted, let alone needed! Building upon it’s success, iFi audio took everything that made the micro iTube great and started over, keeping only the NOS GE 5670 tube! Heavily influenced by their flagship product, the iCAN Pro, built from the ground up using trickle-down technology the micro iTube2 was born! Disclaimer/Acknowledgement The micro iTube2 was sent to me on loan direct from iFi Audio USA in exchange for my impressions and review. The words I write are my own and are honest, objective, and free of bias. I received no financial compensation for my effort, only the satisfaction of trying out a quality product for a few weeks. More importantly, I would like to thank Lawrance over at iFi Audio for providing me the opportunity to review the micro iTube2. Out of the blue I was sent a message here at Head-Fi asking me if I would like to spend some time with their newly released micro iTube2! As a proud owner of iFi products, how could I say no? However, due to popular demand and higher than expected sales by the time our e-mails had crossed back and forth, there were no units left to send out! No worries as I was asked if there was another product that I would be interested in trying out until the inventory levels for the micro iTube2 had been refreshed. How awesome was that? I chose the iPurifier2, and if your would like to read what I thought of the device, click here. So anyway, a short time later a review unit was ready to be shipped out, and here we are today, micro iTube2 in hand. You know what they say, “ All good things come to those who wait. “… or perhaps “ Shut up and take my money! “ might be better suited in this case! About Me Born in 1978, I grew up in a family consisting of musicians, broadcaster/sound engineers, and amateur DJs. I always had a deep appreciation and understanding of both music and sound. I was further educated in this self interest after taking courses in both basic electronics and Sound: Electro-Acousto - The Path to Golden Ears. While I believe a listener’s preference in sound is subjective, the science behind it is not. I am not swayed by buzzwords, hype, trends, brand recognition, or big numbers on charts. Opinionated as I am, my words are not only objective but honest. I view all criticism as constructive, as long as it is sincere. Specifications Tube: N.O.S. G.E. 5670 Maximum output: > 7.75V (>+20dBu) SNR: 119dB(A) re. 2V, buffer, 0dB Gain DNR: 31dB(A) re. +20dBu, buffer, 0dB Gain THD & N: < 0.009% (re. 2V, buffer, 0dB Gain, A- weighted) Frequency < 10Hz -to > 200kHz (-1dB) 20Hz – 20kHz (+/-0.003dB) Response: 1M ohm Direct Tube Buffer 100k ohm Pre-Amplifier with Volume Input impedance: Control Output stage output <1 ohm impedance: Corrected output <150 ohm impedance: Input voltage: AC 100-240V, 50/60Hz Power consumption: <4W idle, 10W max Dimensions: 175(l) x 67 (w) x 28 (h) mm Weight: 278g (0.61lbs) Specifications Tube: N.O.S. G.E. 5670 Maximum output: > 7.75V (>+20dBu) SNR: 119dB(A) re. 2V, buffer, 0dB Gain DNR: 31dB(A) re. +20dBu, buffer, 0dB Gain THD & N: < 0.009% (re. 2V, buffer, 0dB Gain, A- weighted) Frequency < 10Hz -to > 200kHz (-1dB) 20Hz – 20kHz (+/-0.003dB) Response: 1M ohm Direct Tube Buffer 100k ohm Pre-Amplifier with Volume Input impedance: Control Output stage output <1 ohm impedance: Corrected output <150 ohm impedance: Input voltage: AC 100-240V, 50/60Hz Power consumption: <4W idle, 10W max Dimensions: 175(l) x 67 (w) x 28 (h) mm Weight: 278g (0.61lbs) Features - Anodized in ‘titanium’ - Analogue Volume Control - iPower (15V) - 3D Holographic+ matrix for speakers (off/3D+ width/3D+ 30°) - XBass+ for speakers (off/6dB 20Hz/12dB 20Hz) - Tube+ (SET/Classic/Push-Pull) - Tube buffer (0dB/9dB gain) - Tube Preamp (0dB/9dB gain) Brand-new PCB, Direct-Coupled for purest signal path The iTube2, in-line with the latest iFi products, is ‘Direct-Coupled.’ This means no output coupling capacitor for the purest, most direct signal path. Reference class parts quality The iTube2 employs Japan TDK C0G type capacitors. These are complimented by Japan Panasonic ECPU Film Capacitors explicitly designed for audio use with extremely low distortion (<0.00001% @ 1V/10kHz). The iTube 2 also uses ELNA SIlmic capacitors. These and other parts are only found in components with an extra ‘0’ to the price. The proof is in the listening. The best tube buffer/pre-amp out there just pulled even further ahead. ‘Magic’ of SET, Push-Pull or Classic Tube sound In the ‘magic of tubes’ listening stakes, the iTube2 offers the listener the choice of different key sonic signatures: – a Single-Ended Triode power amplifier; – a classic tube amplifier. – a Push-Pull tube power amplifier; Just to note from the iFi team – there is no ‘right’ setting. We advise you to set according to your systems synergy and your listening preferences. XBass+® matrix for Speakers XBass+® for Speakers is quite different to its sister technology XBass+® for Headphones. The only similarity is in philosophy as the ability to enhance your Speaker listening is quite different to enhancing Headphone listening. The former gives each and every audio system adjustable levels of bass control to enhance listening enjoyment through speakers that have limited bass extension. We have taken great care to ensure no degradation in sound quality occurs. 20 Hz (6dB): For speakers missing only the lowest bass notes (below 40Hz). 20 Hz(12dB): For speakers missing some bass notes (below 80Hz). OFF: XBass+ switched out 3D Holographic+® matrix for Speakers The latest 3D Holographic+ matrix for Speakers offers something quite special. It takes high-end systems to another level of performance. It was drawn from the original ground-breaking work of Alan Blumlein, the ‘father of stereo.’ Firstly, it corrects the fundamental spatial distortion in recordings. And secondly, it increases the width of the soundstage beyond that of the speaker placement. 30˚+ : This matrix adds an extra 30˚ to redress the narrow placement of speakers (eg either side of a PC monitor). + : This matrix recreates original ‘width’ of the soundstage and is the recommended DEFAULT setting. Off : 3D+ switched out. Accessories iFi includes everything that is needed; High quality RCA interconnects (+1 for being purple!), an L-adaptor for the iPower to keep the connection flush against the unit, a handy super tiny flathead screw-driver to adjust the DIP switches in the event one’s fingers are unable to toggle them manually, a pad of rubber stick on feet, specification and warranty cards, and for good measures an anti-moisture pack. Packing I am a huge fan of minimalistic yet functional packaging that gives the consumer the sense that they have purchased a quality product, and the iPurifier checks off all boxes on the list. Much like iFi’s other products, the iTube 2 comes in a white, almost Apple-esque sturdy box made of 100% recycled materials free of any toxins that meet environmental standards. The device is nestled in a sturdy cardboard tray with the accessories neatly packaged in compartment underneath; There is no wasted space holding nothing but air, rather only what is needed. A big ‘“hats-off” to iFi for thinking of more than just their bottom-line! Build/Design Measuring 158 x 68 x 28mm and constructed of recycled CNC aluminum, from a build and design perspective the micro iTube2 is purposefully identical to the rest of iFi’s micro line. Every component of the micro line are designed to be stacked with one another so consistency and conformity is a must for both logistics as well as aesthetics. Like it’s line-mates, the micro iTube2’s anodized shell is titanium in colour (albeit a slightly darker shade) with identical body lines and curves. The front and back plates are held together with 4 small screws and adds a nice utilitarian look without being too cluttered or gaudy in relation to the controls. Growing up in the 1980’s I am very familiar with analogue volume potentiometer and toggle switches. Rarely have I encountered a more smooth, solid, and balanced pot as I have on the micro iTube2. Saying that the volume pot is of high quality is an understatement as it not only possess perfectly smooth rotary tension, to my ears there is virtually zero channel imbalance when turned to the lower quarter of the dial! The recessed chromed toggle switches are of equal quality, and possess a smooth yet tactile rigidity.