Mini-I Pro (2015) Review – A Balanced DAC With Headphone AM
Matrix Audio has been in the audio industry for many years and has been garnering positive feedback regarding their DAC and Headphone amplifiers. If you are familiar with the company, I’m sure you know what I mean. However, for those who are unfamiliar with the company yet, this is a good time to know about their products specially if you love music and you simply want to enjoy your music with utmost detail and quality. Today, we are going to review the new Matrix Audio mini-i Pro + 2015 edition, powered by ESS Technology’s ES9016 Sabre DAC paired with a new XMOS chip supporting 32bit/384KHz PCM signal playback and DSD64/128/256 digital signal playback. It features a digital volume control, a nice OLED display, various input and output connectivity options and many more. Find out more about Matrix Audio’s mini-i Pro + 2015 in our review below.

Matrix Audio mini-i Pro + 2015 Review
Before we proceed, I’d like to thank Matrix Audio for providing the unit in exchange for my honest opinion and for the purpose of this review.
Let’s talk about the features of the Matrix Audio mini-i Pro + 2015 first. The company didn’t change the external design of the mini-I Pro 2015 compared to the 2014 model. In fact, it looks exactly the same with the older model, and you wouldn’t notice the difference at all. Most of the changes in the new mini-I Pro 2015 were done internally, and I find it more of an updated version rather than the 2014’s successor. However, I think Matrix Audio could have at least clearly labeled the new 2015 edition to avoid confusion.
In the new Mini-i Pro + 2015 model, Matrix Audio upgraded the XMOS chip inside and now supports up to 32bit/384KHz PCM and up to DSD 256 digital playback. Unlike the non pro version, the mini-i Pro features a high performance 32-bit, 8-channel ESS ES9016 Sabre32 Ultra DAC equipped with Time Domain Jitter Eliminator and ESS patented 32-bit Hyperstream architecture that can handle up to 32-bit PCM data via I2S input, as well as DSD and SPDIF data.
The Mini-I Pro + 2015 also features Texas Instruments’ ultra-low distortion audio op-amp LME49720 paired with a high fidelity TPA6120 headphone amplifier, making sure that the device can drive even the most demanding headphones on the market. It also features a precision digital volume control with OLED display, and a number of input connectors like Optical, AES/EBU, and Coaxial that supports up to 24/bit 192KHz of digital playback. As for output ports, both the balanced XLR and unbalanced RCA output can be connected at the same time. However, depending on your “Working Mode” the RCA line or the headphone out may automatically mute or shut down.
I’ll talk about more of its features as we take a closer look on the mini-i Pro + 2015 on the next page. Meanwhile, you can check out its full specifications below.
Packaging and Closer Look


The Mini-I Pro + 2015 came with a nice clean white box, properly padded with thick foam on top, bottom and the sides. The package includes the unit itself, a driver CD, a manual, a power cord, a USB cable and a handy RM1 remote control. The remote control allows for basic controls like power, volumes up and down, mute button, and source select. It’s really a simple remote control enclosed in slim and sturdy metal (probably aluminum) housing.
Regarding the driver, I didn’t install the driver that was on the CD. But I downloaded the driver from Matrix Audio’s website. Be sure to download and install the correct driver, as the 2015 model has a different driver than the 2014 model.



The Mini-I Pro 2015 measures 6.61″ x 7.87″ x 1.81″, weighs 1.3kg and looks exactly like the 2014 model. The aluminum enclosure looks plain and simple but very study and solid. Later when I opened the unit, I found out that the enclosure is thick and doesn’t bend at all. The unit I got is all black, so it may look a little boring for some. But I’m telling you, it looks gorgeous in the actual, specially when the unit is turned on and see the OLED display.

The Matrix Audio Mini-i Pro has a voltage switch on its left side. It’s compatible with AC 100-120V and AC 220-240V. Be sure to set the correct voltage first before connecting it to a power source and turning it on. Otherwise, it will damage the unit if set incorrectly. Set it to 115V position for AC100V-120V 50/60Hz or to 230V position for AC220V-AC240V 50/60Hz. You may need a flat screw driver or something sturdy to slide the switch, as the hole is too small for your finger.

At the back, the Mini-i Pro 2015 has a number of connectivity options. If you have lots of audio components in your home, you may utilize all these connections. But for most desktop users, the USB and/or Toslink inputs and the headphone out is sufficient enough to enjoy this device. It’s good that you have several connectivity options, who knows, you might need those extra ports someday.

Opening the Mini-i Pro is easy, you only need to unscrew a total of 8 Allen/Hex screws. A caution, opening the unit will void warranty. This is for presentation purposes only. You can see from this angle the voltage switch and a thin layer of plastic underneath the PCB.

Matrix Audio is using EMI (electromagnetic interference) filter to isolate EMI from AC input. The Mini-i Pro has a built-in independent regulated power supply, a shielded Toroidal transformer, a multi-stage filter making sure that the unit gets a robust and stable power at the same time keeping the lines clean and the noise at bay. You can also see from this angle (although not very clear) the XMOS chip and ESS SABRE Ultra ES9016S D/A chip along with other components inside the mini-i Pro.
Now let’s proceed to the next page and find out how this device sounds.
Testing and Subjective Listening

Once you have set the right voltage, plug the power cord and connect the Matrix Audio mini-i Pro + 2015 to your computer via the USB cable. Install the appropriate driver for Windows and power it on. Note: Mac OS X 10.6.4 and above versions have native support and do not require a driver.
When I turned on the mini-i Pro for the first time, I immediately noticed that there was no popping sound, unlike some DAC/Amps I have tried before. Also I noticed that the area of the OLED display is actually quite smaller. I was expecting that it would occupy more space. Nevertheless, the amount of light it emits is just right, not too dim and not too bright as well. Another thing that I like about the mini-i Pro 2015 is its digital volume control. It feels nice to rotate and you get a nice and soft bump or click one notch at a time. Pressing the volume control will cycle from one source to another. You can see from the display that the active source is highlighted in white.
Overall, operating the Matrix Audio mini-i Pro+ 2015 is as easy as listening to it. My primary source is my desktop PC connected via USB cable and I’m using Foobar as my music player. I configured Foobar with an ASIO output because it’s the most convenient configuration for me. The mini-i Pro automatically detects the format of the file and output it as PCM or DSD depending on the source. When the music player is playing a FLAC format, the mini-i Pro will display something like 44.1KHz or 384KHz on the screen, otherwise it will display something like DSD64 for higher formats.

Matrix Audio mini-i Pro+ 2015 Review-11I’ve been listening to the mini-i Pro for more than a month now. And I tested it with some of my headphones that I am also currently reviewing like the Grado SR225e, Master&Dynamic MH40 and some custom IEMs from Heir Audio. I also tried it with some of my older headphones, like the B&W P7 and UE 900s, just to have a good feel with what the mini-i Pro can do.
For me, I find the highs in the mini-i Pro tamed and controlled. The highs have a certain amount of extension and it does have a good amount of sparkle. It’s clear and detailed enough for me to enjoy the music, and above all, I think the highs are smooth and not sibilant. This was noticeable when I plugged the SR225e with the mini-i Pro. Before, I wasn’t accustomed to headphones that are natural and bright, and I always like warm sounding headphones. The mini-i Pro helped in smoothing the highs of the SR225e and at the same time somehow improved its bass response.
Matrix Audio mini-i Pro+ 2015 Review-12Mids on the mini-i Pro are fantastic. They don’t sound laid back, but rather they sound just a little bit forward. It’s forward enough to make the artist’s voice sound engaging and lively. This is something that helped my UE 900s improved in terms of its mid-range. A lousy mid-range would have ruined the whole synergy of the music, and I don’t believe that the mini-i Pro disappointed me at all in this section.
Like my portable setups, ALO Audio’s The International+ and iFi micro iDSD, the Matrix Audio mini-i Pro has a hint of warmness despite being neutral and balanced. Bass response is great, it doesn’t make your headphones sound boomy. I think the bass is well extended, but at the same time well-controlled and doesn’t bleed into the higher frequencies. It’s not overpowering as well, but it can bring out the bass in some headphones like the SR225e.

The Sound stage in the mini-i Pro is great, instruments are well separated and they don’t sound like they are cluttered into one group or in the mid-section. Overall, I find the sound that the mini-i Pro produce is lush, fun, musical, never fatiguing and offer an enjoyable experience.
Just a bonus, I tried playing some games, specifically The Witcher III Wild Hunt, just to see how it compares with the onboard sound card that motherboard companies nowadays are bolstering. Honestly, they don’t even come close to the audio quality that the mini-i Pro produces. PC gamers don’t usually invest on something like an external DAC/Amp, but for those of you who like to enjoy high quality music like me, I think it’s high time to considering getting an external DAC/Amp for your desktop.
Price and Where to Buy
The Matrix Audio mini-i Pro + 2015 is available now and comes with a retail price of $519.95. It’s available in Black or Silver and can be ordered from store.matrix-digi.com here. It also comes with a 1 year manufacturer’s warranty.
Matrix Audio mini-i Pro + 2015 Review: Conclusion
We all have different ears, thus we have different perspective, tastes, and preference. For me the Matrix Audio mini-i Pro+ 2015 is a very competitive and promising desktop DAC with Headphone Amp considering its price. I’m not saying that it’s the best out there since there’s always something better. But for the price, for me it’s definitely one of the best in its price rage. It left me with a good impression and it definitely didn’t disappoint.
Now, I haven’t tried the older 2014 model so I am not sure if there is a change in the sound quality/signature. But I don’t see the mini-i Pro 2014 model being listed anymore, so I guess Matrix Audio intends to replace the old one with this new model.

In terms of build quality, it’s definitely solid and built like a tank. Most area of the body looks plain, but the front OLED display adds attraction, to complement its simplicity. I just which Matrix Audio could have maximize the extra space in the front section for more display functions, like visualization or spectrum display. When it comes to sound quality, you’ll have to back read on that.
Finally, the Matrix Audio mini-i Pro+ 2015 is an overall well-rounded DAC/Amp, with lots of features, support for different audio formats and connectivity options. I think it would make a superb investment specially if you are looking to upgrade your desktop’s (or sound system’s) audio quality.