Colour it in with iFi Audio’s iTube2

  • Colour. In hifi, it’s unavoidable. Consider two different amplifiers (or two different phono pick-ups) that sound different to one another. If you’re an absolute sound chaser, one must be, by definition, coloured. To those with a less idealistic audio aim, both are coloured. And if we can’t avoid colour, why not embrace it?

    At its most basic level iFi Audio’s iTube2 suggests that we make colour work in our favour – to satisfy subjective enjoyment – deploying it as a transportable tube pre-amplifier (with 9db gain) or, Peachtree nova150/300 owners take note, as a tube buffer to lend music a richer, fuller presentation with more abundant midrange bloom.

    Positive side-effects also include a possible improvement to the impedance relationship to the two devices between which the iTube2 sits. Better impedance matching can sometimes be especially potent for those running a DAC/pre directly into a power amplifier.

    As its name suggests, the iTube2 is a second generation product. However, as per their recent Black Lightning iDSD revision (review to come), iFi Audio’s engineers haven’t gone in for a nip here and a tuck there but a complete product reboot. The only feature common to both first and second generation iTube units is the bottle itself: a GE5670.

    A little history from iFi’s website:

    “The 6922 tube/valve is one of the most famous ‘dual triode’ designs and is ubiquitous. It has and is still, used in many tube/valve audio products from CD players to headphone amplifiers.

    First introduced by Western Electric in 1946 with the WE396A, from the 1950s onwards (and for the next 30 years thereafter) General Electric (and several other tube/valve manufacturers) followed Western Electric with their own premium version of 6922. This range had controlled warm-up and tight specifications on grid-current, noise and microphony. The result, significantly smoother and more organic sound qualities.”

    On parts selection for the iTube2, iFi Audio have opted for “ELNA SIlmic capacitors and Japan TDK C0G type capacitors” complimented by “Japan Panasonic ECPU Film Capacitors explicitly designed for audio use with extremely low distortion (<0.00001% @ 1V/10kHz)”.

    A toggle switch engages three modes of operation – ‘Classic’/Push-pull/SET – and adjusts the amount of feedback running through the device’s Class A circuit.

    Colour application isn’t restricted to the tube itself. Additional toggle switches engage the iTube2’s analogue (not digital) signal processing circuitry for optional bass boost (20Hz, 6db or 12db) and/or 3D ‘Holography’, the latter reportedly useful for loudspeakers unable to enjoy proper physical separation.

    Juicing the whole shooting match with 15V is iFi’s ‘Low Noise’ iPower switch mode wall-wart.

    Price? US$375 (before sales tax), €450/£375 (incl. VAT).

    Further information: iFi Audio

    John H. Darko

    Written by John H. Darko

    John is the editor of Darko.Audio, from whose ad revenues he derives an income. He is an occasional contributor to 6moons but has previously written pieces for TONEAudio, AudioStream and Stereophile. John used to live in Sydney. Now he lives in Berlin.

    Follow John on YouTube or Twitter


    1. I don’t have a problem with colour as such. An actual tube output, warmish sounding film caps, cables that add meat to the bones, a midrange bump in a speaker crossover can all add to the musical enjoyment if done properly.
      However I do have reservations about adding an additional device in the chain who’s sole purpose is to add colour.

      • But it’s sole purpose isn’t to add colour. As per the above the text, the iTube2 can also improve impedance matching between pre and power.

    2. I’m considering putting one of these between a metrum musette and a pair of active speakers, just wonder if the attenuator is up to snuff.

      • Well, the iTube2’s attenuator is all analogue. And is it likely to be weaker than the attenuator found in your actives (should they have one)?

        • Current actives do, the A’engine A5+, but searching for the elusive “perfect” active with AB amps and little or no other BS included.
          Alas, the search continues…

        • If it is a Cermet type pot then it may be rugged than most carbon or plastic types. I just read parts of the manual, interesting that it can be used for car audio powered by 12V batt power..

    3. It’s an interesting and seemingly fun device. I mean, dialing in direct SET sound, PP power, or vintage tube bloat, what a blast that would be!
      Probably must get one…

    4. Hi, I have the original itube which has ‘digital antidote plus’. Seems this feature has been deleted and the extra bass added. I wonder if there any reason why? Thx

    5. I’ve used the original version for a couple of years. I find the “3d” feature stunning in its effectiveness in opening up the soundstage for a less than ideally set up listening space. There is a similar 3d circuit on their headphone amp, the ICAN, that I’ve also found addicting. However, the tube feature on this first version I always found subtle at best.

      Now that I’ve been using the new ifi itube 2 a couple of days, I find the new tube settings are anything but subtle — really quite fun. Thanks Darko for lightening up my wallet (again).

      • I have used the 3D feature and have really found it to benefit my desktop experience. The difference is very noticeable. I just wish they had a DAC with the 3D so I wouldn’t have to have two separates for my budget desktop speakers. i have yet to try the 3D on my upscale loudspeaker system.

    6. “Peachtree nova150/300 owners take note, as a tube buffer to lend music a richer, fuller presentation with more abundant midrange bloom.”

      How? If my cd transport is fed into the peachtree’s DAC, how would i be able to employ this as a buffer?

    7. Angelo –

      The new Nova’s have a loop option. Hook the iTube2 up to the loop inputs/outputs, hit loop on the remote. I’ve been using an iTube2 like this for the last several days. Really interesting as it allows instant A/B comparison (remote switches loop on off, music doesn’t even pause).

    8. I’d love to see a full review of this, particularly as it stacks up against a Schiit Saga or similar.

    Softbank-owned Sprint acquires 33% of Tidal

    Classy! Sonore’s microRendu takes digital audio higher