This week we will be reviewing the iBasso D-Zero MK2, a portable USB DAC and headphone amplifier. The strengths of this small digital-analog converter are: its battery, its compatibility with computers, smartphones, tablets (Apple, Android). It is able to extract digital audio signals up to 24 bits / 96 kHz while offering a powerful analog amplification that enhances the performances of any iPhone, Galaxy S5, iPad or Nexus headphone output.
We will discuss how this small device can indeed enhance the sound of absolutely any smartphone or tablet, including sources with a really mediocre headphone output.
iBasso D-Zero MK2 : double Wolfson WM8740 DAC on board
The iBasso D-Zero MK2 portable DAC is the second version of a converter which has already met with quite a success, the iBasso D-Zero. Although the brand made a few adjustments to the MK2, the true revolutionary change brought to the iBasso D-Zero MK2 is the use of two Wolfson conversion microchips instead of one. Even the audiophile player iBasso DX50 only uses one, but we will discuss it later.
iBasso D-Zero MK2: box contents
The iBasso D-Zero MK2 comes with several accessories made for its portable use. The micro-USB to mini-USB cable, called USB OTG, lets you connect the DAC to a smartphone or an Android Tablet. Watch out: the Android version needs to allow digital output via the USB port, or needs to be rooted so you can use an app allowing it (this function is essential for the D-Zero MK2 to work). As for iPhones, iPoud touch and iPads, this DAC can decode everything as long as you are using the Apple Camera Kit. The 3.5 mm to 3.5 mm mini-jack cable can be plugged into the headphone or line output of any stereo audio source, especially MP3 players.
iBasso D-Zero MK2: an explosive portable player
If you think the sound of your smartphone is weak and dull, this iBasso D-Zero MK2 is the ideal solution to this problem. There is no magic involved, it’s all about the impedance. As a reminder, the impedance is the resistance of a speaker or a set of headphones to the electric current delivered. The weaker this resistance is in the lower end of the sound spectrum, the more power the headphone amplifier has to provide. The result is a complete performance collapse of the portable device or smartphone’s headphone amplifier in the low frequency, which will then deliver a distorted sound and a completely flat sound stage. The iBasso D-Zero MK2’s line input has a linear impedance, thus letting the headphone amplifier function in an optimal way. When listening to a Samsung Galaxy Note smartphone and a Google Nexus 7 tablet we definitely noticed a slight increase in the low frequencies and a better articulation of the notes.
Listening to our Galaxy Note, usually tiresome, became a whole new experience with the iBasso D-Zero MK2, which brought a significant amount of extra power.
Two DACs, twice as good’
Let’s be honest and acknowledge the fact that converters equipped with 2 or 4 DACs have a tendency to put an amused smile on our faces at first. Yet, iBasso is no novice in this game as its top-of-the-range audiophile portable player the iBasso DX90 is equipped with two ESS Sabre 9018 K2M DACs. The goal is to dedicate a Wolfson WM7840 to each channel in order to drastically reduce the signal distortion (thus impacting the signal/noise ratio) and to enhance channel separation. The result is striking and the only thing left to the very good Encore mDAC (the most serious competition of the D-Zero MK2) to stand against the iBasso D-Zero MK2 is its vintage sound signature.
We connected the iBasso D-zero MK2 to a computer using Windows and Foobar2000 with ASIO4ALL and WASAPI drivers in order to bypass Windows’ mixer and avoid any possible modification of our files.
A true feeling of controlled sound emanates right from the start. Low frequencies are extremely solid, mediums are detailed and the treble crystalline. The delivery is dynamic without being blunt and always creates a nice sound stage.
5th Symphony, Trauermarsch. In gemessenem Schritt. Streng wie ein Kondukt. Gustav Mahler (FLAC 16/44)
No more possible doubt here. The two DACs set in parallel have a real impact on the high frequency delivery. Very little intermodulation, the horns are well placed and do not take over the strings. The overall coherence is great, which is unusual for this range of products.
Duel of the Fates, John Williams, FLAC 16/44
The two DACs show what they have to offer, by chiselling the high frequencies with a striking accuracy while never holding back on the drum rolls. The sound of the choir is absolutely majestic. The scale is enjoyable and never do we want to turn the volume down, quite the contrary.
Haunted, Beyoncé – FLAC 16/44
We listened to this track in order to see what this iBasso D-Zero MK2 could do when it had to go down to the lower end of the sound spectrum. The answer is simple: the diaphragms on our Sennheiser headphones were making a slight mechanical sound which is the symptom of an excursion that would be too long. In other words, the iBasso D-Zero MK2 dives really low in the sound spectrum and delivers a lot of power when it comes to infra-bass. Besides, there is enough articulation so the sound doesn’t turn into what would come out of a fun fair speaker.
Seul ou accompagné, BB Brunes – FLAC 16/44
A pretty furious track, almost hard to listen to as the guitars and the drums are all competing against each other while the singer is almost screaming more than he is singing. Besides, the recording is not exactly generous in low frequencies which isn’t the most enjoyable thing your ears can experience. Yet, the iBasso D-Zero MK2 is very comfortable and never loses track of the bass line, which lets the listener catch more details and variations than usual in the voice of the singer.
Non Violent Integration, Duke Ellington and his orchestra, FLAC 24/192
The instruments have a remarkable tone, the sound stage is wide, the balance between bass and treble is nothing short of outstanding.
Flying in A Blue Dream, Joe Satriani, FLAC 24/96
The complexity this track offers is well highlighted, the guitar sound stands out from beginning to finish.
The formula is quite simple: a battery + a pair of top-of-the-range DACs set in parallel + a good headphone amplifier = audio delight. It looked like an impossible bet given the price of this D-Zero MK2. We even took it one step further by pairing it up with a Marantz PM-6005 amplifier (review soon to be available) and we were not disappointed, and it’s quite the euphemism. This is an excellent USB DAC, to use as a portable device or in the comfort of your own living room.