Me: I am a 21 year old Engineering student living in a small town in India. I would like to call myself a music enthusiast, rather than an audiophile. I was inspired by music since childhood, and as the time passed, the passion of music grew in me, and that subsequently led me to join Head-Fi. Eventually, I found the pleasure of listening to music mainly by the HD600 and recently, by the seductive LCD2 headphones, and realized the true components of recorded music. I usually like to listen to Indian Classical Music along with Bollywood songs. My main listening genres include classical, vocal, instrumental, jazz and sometimes pop.
Intro: Audinst, is a renowned Korean headphone amplifier manufacturer. They are based in Incheon, South Korea. The brand was established in 2009. All their products are made in Korea.
Specifications of HUD-Mini as per Audinst:
Interface: USB 1.1/2.0 SNR: 113dB
Sampling Rate: 16/24 Bits 44.1/48/88.2/96 KHZ
Output: 6.5mm/3.5mm headphone Jack,
RCA Line out & Optical out
Headphone Impedance: 16-300 Ohms
Weight: 160 grams
Let us see what the HUD-Mini has got for us,
Packaging and Accessories: The HUD-Mini arrives packed inside a large colourful cardboard box (typical Audinst Style), on which features and other information have been mentioned upon. Once the box is opened, the main unit and all accessories are put in a foam packaging. Accessories are found beneath a pseudo-bottom compartment. No complaints here. Nothing special to mention about either; all accessories have a good quality, build and feel to them.
List of accessories in the box, which include the following:
USB Cable: Standard black coloured USB A to B cable, 1.5 metres long.
RCA Cable: Audio cable for Line out function, about 1.5 metres long.
Rubber Feet: For attaching to bottom surface of HUD-Mini, thus making it scratch and skid resistant.
User Manual: Detailed and informative Instructions about operation, also contains warranty information.
Design and Build: The HUD-Mini has a very good overall build quality.
The outer case is made up of aluminium, and is painted in greyish silver. Front panel is black coloured; volume knob is rubberized, and has a grippy feel to it. In pictures HUD-Mini looks larger, but in real, it is quite compact in size.
On the front side, we have Volume control knob, an output toggle switch (between headphone out and Line out) and an output headphone jack is present in both 6.5mm & 3.5mm format. An active colour changing LED indicator shows the status of operation. The LED turns green once songs/signal start playing from the source, and stays orange incase there is no signal incoming. On the rear side, we have USB input port, RCA Line-out jacks & Optical output port.
Speaking of Internals, HUD-Mini has a double sided PCB with no wirings. All components used are of premium brands; including all dale resistors, Alps pot, premium caps. The HUD-Mini employs a 24/96 VIA Chip (which obviously has 88.2 support over the popular Tenor’s) There is only one user replaceable part on board the HUD-Mini: The DAC output Op-Amp (which is by default LME49860 in DIP8 format) other op-amp is AD8397 but it is permanently mounted on PCB. Audinst has always been a strong contender in the field of Build, interiors, components and PCB. The HUD-Mini stays & operates very cool no matter what.
The HUD-Mini is powered solely off the 5V USB line. This makes it also to work straight off an android smartphone, which is a definite advantage for travellers. The HUD Mini also has Line out for speakers or external amps, which again works quite well with crisp and clear output. But the volume control will no longer function when line-output is selected.
Sound: I feel the HUD-Mini is neutral, detailed and accurate in sonic presentation. Sound-stage width is moderate. Depth is pretty good. Absolutely zero audible hiss/noise. No channel imbalance, and zero EMI pickup & pops.
Lows are strong and accurate and go fairly deep. Infact, Mids natural and clear, slightly intimate if I must say; Highs are clean, airy and non grainy, just right amount of sparkle to keep the music alive.
Soundstage on HUD-Mini is very good, and realistic and to some extent, lacking in width. Depth is fair. HUD-Mini does not give a fully circular imaging, instead gives out an elliptical stage (with comparatively more depth and lesser width) Detail retrieval, and dynamics are decent enough. Overall the sonic presentation is very much neutral. Also, the final sound impressions of HUD-Mini can be manipulated by using different op-amps. I have changed to Op-Amps and I could observe that the current op-amp (LME49860) does a very fine job, and I feel there is no need for op-amp rolling to increase sound quality. But the HUD-Mini scales very well with any op-amp installed.
As per my observations & comparisons, The HUD-Mini is going to be the most ‘clear & neutral’ sounding amp/dac from Audisnt. Its higher end counterpart MX-1/2 did not quite please me, owing to their dark-sound character.
Comparison: The only competitor for the HUD-Mini is its fellow Koran amp/dac: Audiotrak’s Prodigy Cube (99$), which too has very similar functions, features and circuit design. But the Cube will have slight edge & advantage over the HUD-Mini in terms of features (Coaxial and microphone support) but in terms of sound quality, both are neck-to-neck, with Cube providing a slightly warm, smooth and laidback sound character, and HUD-Mini providing a little more upfront and clear signature.
Conclusion: HUD-Mini is a great sounding portable amp/dac in its price point, Infact, the sonic performance is the best one can get in sub 150$ portable amp/dac’s. This device is actually pretty great on features and practical aspects. At the price point of 120$ shipped, HUD-Mini stands as best option for travellers with smartphones or laptops. I can recommend HUD-Mini for any music enthusiast who wants a handsome portable USB amp/dac to drive low impedance headphones.
1) Design and Build: HUD-Mini has very well designed and implemented build. It can run off 5V source, eliminating the use for a separate power supply. The HUD-Mini can also run directly on android smartphones. It is also very compact, with practical features.
2) Sound quality: The sonic presentation on this little unit is neutral and vastly uncoloured. Default op-amps LME49860 & AD8397 perform very well, I can imagine it would pair well with almost any headphones.
3) Value: The HUD-Mini unit carries a great price to performance factor, which is hard to beat in this price range. Perhaps the HUD-Mini is the best portable amp/dac in this price range.
1) Fixed Volume in Line-Out: Alright, so this is not really a flaw, but it would have been perfect if the HUD-Mini had volume control working even under Line-out mode. Thats it, apart from this I am unable to find any drawback or flaws.