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NuPrime Audio Hi-mDAC Review
Jason Lim at Nuprime Audio graciously sent me a Nuprime Audio Hi-mDAC to review in advance of the release during the CanJam NYC weekend of February 15-16, 2020. This will replace the older, larger, and discontinued uDSD USB DAC - being much smaller and compatible with mobile devices as well, while still offering high quality analog and digital outputs. I have not heard the uDSD, so I cannot compare them. I did compare to some competitor’s products.
https://nuprimeaudio.com/product/hi-mdac/?v=7516fd43adaa
GENERAL INFO: MSRP $129. Measuring 5.0cm x 2.2cm x 1.2cm.
SPECS: Hi-mDAC utilizes a new chip, CS43131 from Cirrus Logic, together with a NuPrime customized low power USB communication chip.
PCM decoding up to 32-bit /384Khz.
Increased hi-fi DSD playback rate from DSD128 to DSD256.
Integrated GND-centered, Class H headphone driver.
Output level up to 2 VRMS into 600 Ω headphones (can be used as a pre-amp to feed another amp).
Frequency Response 20-20Khz +/- 0.5 dB.
Evolved performance: THD+N 0.005% at 1Khz.
S/N Ration >100 dB (20-20Khz A-weighted).
Ports: USB-C, Combination 3.5mm analog audio output and 3.5mm S/PDIF converter (PCM192 and DoP64).
Output power:
30 mW per channel into 32 ohm load
5 mW per channel into 600 ohm load
FIT AND FINISH: The top of the Hi-mDAC has a silver tone mirror finish with the company logo. On one side are volume up and volume down buttons, with no gaps or spaces between the buttons and side of the case. The other 5 sides are all a brushed aluminum finish. There is a very fine seam where the top and bottom half of the CNC machine case come together, and the edges are flush.
The volume buttons have nice feedback, and don’t so much as click when depressed and they bounce back when released. The Hi-mDAC included USB-A to USB-C cable feels like it’s high quality, with a nice soft-to-the-touch woven fabric jacket, and not some thin cheap rubbery coating. Plugging in the USB-C cable results in a click and firm/tight engagement. The same is felt when plugging a headphone into the 3.5mm jack.
MUSIC SELECTIONS - I chose a variety of lossless music including but not limited to the following - Jack Johnson “On and On”, Dianna Krall “Live in Paris”, Ed Sheeran “X Wembley Edition”, Martin Garrix “2019 Remixed”, Camilla Cabello “Romance”, Amanda Palmer “Performs the Popular Hits of Radiohead with her Magical Ukulele”, Eric Clapton and BB King “Riding with the King”, Post Malone “beerbongs & bentleys”, Taylor Swift “Reputation”, Zac Brown Band “Welcome Home”, Chris Jones “Roadhouses and Automobiles”, Billie Eilish “When we all go to Sleep, Where do we Go?” and “don’t smile at me”, Dierks Bently “Riser”, Eric Church “Chief”, Zara Larsson “So Good”, Pink Floyd “DSOTM”, Blueport Nuforce Jazz Sampler, and Timothy Seelig “Rutter: Requiem & Five Anthems”.
GEAR USED - 2014 Macbook Pro 15” on Mojave with Nuprime Audio Hi-mDAC $129, CEntrance DACport HD $149, BlueDAC $399 (similar sound to DACport HD and DACportable), iPhone 11 Pro Max with lightning cable adapter, and iPhone directly into Hi-mDAC using a USB-C to lightning data cable from Penon Audio $39. NXEars Sonata, Basso and Opera balanced armature IEMs. Westone W1, W40 and W80 balanced armature IEM. V-Moda Crossfade Wireless II, Audeze Mobius, and CEntrance Cerene dB portable over-the-ear headphones. Sennheiser HD-600 with APureSound V3 cable with 3.5mm plug, and HiFiMan HE-560 with a Moon-Audio 3.5mm Silver Dragon cable.
SOFTWARE - iTunes 12.9.5.5, Tidal app for OS X, Rogue Amoeba SoundSource. SoundSource offers additional gain via “boost” button to drive HD-600 and HE-560 louder than Mac OS X would normally allow, without distortion. It also offer a distortion free EQ if needed, and allows you to select the system source plus a different DAC/source for several different audio apps.
Nuprime suggests setting the system volume level to 100% for the best dynamic range, and then using the hardware volume buttons to adjust the listening volume, and I agree. But if you are lazy, being able to use the system volume and Macbook volume buttons to control the music in a pinch is very convenient. Certainly more convenient than with the DACport HD which disables the system volume buttons on the keyboard. When you first plug in the Hi-mDAC, both the system volume and hardware volume levels will be reduced, so that you don’t get blasted too loudly with music when you hit play.
SoundSource lets me adjust the system volume via a slider, even when a DAC/amp like DACport HD disables the Macbook volume buttons. In order to do an apple-to-apples comparison of volume settings between the Hi-mDAC and other DAC/amps, I had to max out all their hardware volumes and use SoundSource app to adjust the system volume and then note the percent of volume that they required to volume match. The Hi-mDAC has a lot of steps in the volume control, too many to easily count the steps and say “I was on step 24 of 64 while the blah blah DAC/amp had the volume knob at 20%” etc. I don’t even know how many steps it has, but it’s a lot.
SOUND AND TONE - The Hi-mDAC has a very neutral, flat, and transparent or uncolored sound signature. I would not call it a warm sound signature, but it’s not cold either. In comparison to the CEntrance DACport HD and BlueDAC or HiFiMan R2R2000, I would say the R2R2000 sounds the warmest and most lush, and the CEntrance products are slightly warmer and punchier than the Hi-mDAC but still leaning towards neutral and transparent.
The sound and tone depends on the program material and headphones that you chose to listen with, so I tried to mix and match various amps + headphones + music, which gave me an overwhelming combination of choices to report on; but I’ll try to do my best to break it down for you here. I think that next time I will discuss all the aspects of sound with each IEM or headphone as a whole, instead of breaking it down by bass, midrange, treble, etc.
BASS - With any of the IEM that I tested, the mDAC has strong bass delivery, which is deeply extended. The bass is controlled, tight, and fast as well. It has no peaks or troughs that I noticed. But in comparison to the DACport HD, I’d say that the DACport has a little warmer and punchier sounding bass, which depending on the headphones that could be better or worse.
As above, I use Rogue Amoeba’s “SoundSource” app on my Macbook to direct sound to whichever device I wish to listen, and it also includes some preset EQ choices, like bass booster, treble reducer, etc. Using the bass booster setting with the Hi-mDAC and IEMs works very well, and and with the gain boosted with SoundSource it does not drive the amp into clipping with any of my IEM or expensive full-size headphones at normal to very loud volume levels.
But I found that my over-the-ear high-efficiency lower-cost portable headphones are more easily driven to distortion at extreme volumes, unlike the full size desktop-class headphones. But all of my critical listening was done with NO EQ unless specifically testing the amp’s ability to handle extra bass without clipping.
While playing random songs in Tidal with the NXEars 8-driver Opera IEM, Eric Church’s song “Over when it’s Over” came up, and the weight and foundation of the kick bass drum really took me by surprise - I could almost feel it in the room with me. With the same tracks, I switched to the CEntrance Dacport HD where the bass impact increased and it sounded slightly warmer - the Opera are less picky about the amp than the Sonata or Basso IEM from NXEars, and so the bass didn’t change as much with a change in amp.
I then listened to Timothy Seelig, Rutter Requiem III: Pie Jesu, and the bass of the pipe organ reaches to subterranean depths with the Hi-mDAC, with all of the IEM and even with the HD-600. While the pipe organ bass is deep and extended with HD-600, it’s bass impact on some other genres of music doesn’t impact quite as hard as it does with a more powerful amp with higher voltage swing. But with the album “Kool Cats” by Guinea Pig, the string bass with the HD-600 was very tight and punchy, and the Hi-mDAC volume with HD-600 was moderately loud and very clean all the way up to 100% system volume.
The following is almost more of a review of the over the ear portable headphones than the Hi-mDAC, but I wanted to talk about how it drives a variety of portable or transportable full-size headphones that I have readily available. I usually do not amplify these headphones, and a couple of them I usually only use via bluetooth.
The V-MODA Crossfade Wireless II is known as a bassy headphone, and with the Hi-mDAC at just 50% volume their bass is massive with the string bass on Guinea Pig “Kool Cats”. The V-MODA bass was a little too much with both the mDAC and DACport HD. With Rutter Requiem Pie Jesu the pipe organ has power and weight, but the HD-600 still had better bass quality and control than the V-MODA with the Hi-mDAC.
I usually prefer to use the V-MODA with old classic rock recordings that didn’t have a lot bass in the mastering, or to use at low volumes where I would otherwise might want a loudness control. I also have not used them in wired-mode more than 2-3 times and usually am using them with Bluetooth. But, when playing the Guardians of the Galaxy soundtrack and a variety of Led Zeppelin recordings via Hi-mDAC and Tidal lossless, they had good bass balance, while the DACport HD had similar bass but pushed the midrange too forward.
The CEntrance Cerene dB closed headphone was a better match for the Hi-mDAC than the V-MODA. Before burn-in the Cerene dB were a bass heavy (almost sloppy-bass) headphone, but after they were fully burned-in their bass had become tighter and more controlled. The bass still hits very hard and is a fun headphone with the Hi-mDAC and all my classic rock, electronic, jazz, and classical.
But with songs like Post Malone “Paranoid” and “Psycho” the Cerene dB bass overpowered the midrange and treble on the Hi-mDAC. Switching to the DACport HD from the same company brought the midrange up to a level closer to the bass, but at the expense of soundstage. Just switching to Eric Clapton “Unplugged Remastered” put the Hi-mDAC on top again, with a more balanced tight bass and bigger soundstage.
My Grado HF-2 had strong bass and good control with the Hi-mDAC, but the Grado HF-2 also needs to be your “low volume quiet listening” headphone with the Hi-mDAC, due to exacerbating the Grado’s inherent wall of sound and grainy treble. At low volumes there is no need for bass boost or a loudness control with the HF-2, and I was really enjoying them at 25-30% system volume (with buttons maxed out), but cringing at very high volume which occurs at only 50% system volume.
I pretty much only ever use my HF-2 with my $3000 Eddie Current ZDT amplifier which is so silky smooth and refined in the highs that I can crank up the Grados without fatigue. But, it’s a headphone that I often don’t like at high volumes, and none of my portable amps improve that (the TTVJ portable Millet Hybrid was the best with Grados, and I miss it but sold it due to the tube rush with IEM).
The last headphone I tried with the Hi-mDAC was the HiFiMan HE-560 with Moon-Audio Silver Dragon 3.5mm cable. This is a headphone that I thought likes an amp with a lot of current, and thrives on my 2 watt Schitt Audio Magni 3 amp, so I almost didn’t bother trying it. Even the manufacturer didn’t expect it to be a good match. I was really taken by surprise when the Hi-mDAC can drive the 560 to good/moderate listening volume levels, with tight, fast, and strong bass and everything else)! It didn’t seem like it was running out of current or straining at all.
This combo is even better than the HD600, and it also responds well when the SoundSource “boost” gain mode is enabled. Even with gain “boost” turned on at the same time as bass boost mode (was just as a test), the Hi-mDAC did not give up and barely got warm. I listened the rest of the time with normal gain and NO EQ, and was very impressed with string bass and pipe organ, as well as electronic music from Steven Garrix and Infected Mushroom. I liked the Hi-mDAC and HE-560 combination with just about every song that I listened to, and this was my favorite full-size headphone combination. Only a few times did I want to use the gain “boost” button.
MIDRANGE - The midrange is true and clean, transparent and uncolored, and does not add to or remove anything from the music. Any changes in sound were due to the sound characteristics of the IEM or headphones used, not due to the amp. It’s like “wire with gain”.
For example, when I was doing my NXEars review over the past week, I found that the DACport HD could make the midrange presence a little overwhelming with the 4-driver NXEars IEM or my V-MODA at very high volumes. But the Hi-mDAC did not give me this problem and the midrange was very smooth and natural, even with headphones that usually have a U-shaped frequency response.
The Hi-mDAC midrange was open and transparent with any IEM or full-size headphone I used, even the V-MODA (which had a little too much mid bloom with the DACport HD). With the Cerene dB and Hi-mDAC the midrange was not recessed, so much as the bass was sometimes boosted in relation to the midrange. But I thought the Hi-mDAC did a good job with the Cerene dB on instruments in “Kool Cats” such as saxophone and trombone (un-like with Post Malone).
With Eric Clapton “Before You Accuse Me” on the “Un-Plugged Remastered” album, the clapping to the music sounded natural and real, and not like rain on a metal roof like you get with some gear. Some people have complained that the HE-560 has a U-shaped frequency response with recessed midrange, but I didn't think the midrange was missing on these with the Hi-mDAC.
TREBLE - The treble is usually sparkly and shimmery, maybe too much so in the first 2 days before burn-in, but it settled down quite nicely after about 4 days of music through it.
After burn-in I found the treble to be very detailed and crisp, transparent and smooth, without any veil or grain (if not listening to a Grado which need tubes). Sibilance is not exacerbated with the Hi-mDAC either. It brings out the best of the treble qualities in all of my Westone IEM, Sennheiser HD-600, HiFiMan HE-560. With the Cerene dB and V-Moda Crossfade Wireless II (wired mode) I wished for a little more treble.
My Audeze Mobius sometimes felt a little bright with the Hi-mDAC at higher volumes, but I hear this a lot on the Mobius with music on my iPhone with them. I mostly use the Mobius to watch movies on my MacBook or TV via bluetooth, where it excels at 3D sound with movie and games. The DACport HD had smoother treble with the Mobius and HF-2, but the midrange became too forward so I preferred the Hi-mDAC overall, just at lower volumes with these portable headphones.
The NXEars IEM worked best with Hi-mDAC when using the upgraded pure single crystal 6N copper cable and small tips/deep insertion. Otherwise, with the silver plated copper cable they’d sound a little bright on the Hi-mDAC vs with the other amps I tried. Because of how well the Hi-mDAC works with the HE-560 on a silver cable, I’d say this was an “IEM on the wrong cable” issue, not an amp issue.
IMAGING AND SOUNDSTAGE - The Hi-mDAC has good soundstage and imaging, and it sounds effortless and transparent in it’s presentation. I felt that it sounded a little more open and spacious, and less intimate sounding than the CEntrance products (or R2R2000). I preferred the Hi-mDAC with my Westone W1, W40, and W80 IEM, which gave the Westone a little bigger soundstage than with the CEntrance DAC/amps.
The NXEars IEM all seem to have a little bigger soundstage regardless of amp, and paired a little better with the punchier CEntrance amps. However, the NXEars still sounded very good with the Hi-mDAC, and this is the amp that I used exclusively for the first 2-3 days of my NXEars IEM review that I posted earlier this week. This combination frequently gave me some out of head cues while listening, and a couple of times I looked around to see what was making a sound only to realize it was in the recording.
The HD-600 and HE-560 full-size desktop headphones also sounded a bit more open and spacious with the Hi-mDAC than my CEntrance amps, despite the extra power reserves of the CEntrance amps. Note - I do think the balanced 2.5mm output of my BlueDAC is more open sounding with better separation than the 3.5mm jack I was using.
POWER OUTPUT AND SYNERGY with different headphones - Gear synergy is important, and different IEM and headphones can change the sound characteristics, depending on how they interact with the Hi-mDAC’s output impedance. I do not know the output impedance, but If you don’t like the Hi-mDAC with one IEM or headphone, I say try another before giving up.
How well a headphone paired with the Hi-mDAC also depended on the source material, and while I would not listen to Post Malone “Beerbongs & Bentleys” with the Cerene dB and Hi-mDAC at high volumes, the pairing sounded great with Eric Clapton “Unplugged Remastered” or Guinea Pig “Kool Cats” at any volume.
Listening fatigue can also play a roll, and after listening to music with the Cerene dB for 2 hours straight, when I switched to Taylor Swift “Reputation” I thought that the bass was much better controlled than with something like Post Malone “Beerbongs & Bentleys” but it sounded like all the treble had disappeared. I had to take a long break after this. This did not happen with long listening sessions with my IEM or the HD-600 and HE-560, but my portable over-the-ear headphones contributed to fatigue much faster than the others.
I thought the Hi-mDAC had great synergy with Westone W1, W40 and W80. It also paired well with my V-Moda Crossfade Wireless II and Cerene dB with classic rock (or if playing anything at low volumes). In comparison to its nearest competitor, the DACport HD is a warmer and more powerful amp, and I found that the NXEars IEM sometimes had a little better synergy with the DACport HD (it was a toss up with the 4-driver Basso).
Synergy with my HD-600 and HE-560 was very good with the Hi-mDAC. I really enjoyed the combination and I only occasionally needed to max out the system volume and hardware volume buttons to get the desired volume, especially with some classical music like Rutter Requiem, or some jazz and new age tracks. If I needed more gain I could use SoundSource’s Gain “Boost” button to get more system volume with these quiet recordings.
With Jack Johnson playing “Taylor” or “Dreams be Dreams”, or Halsey playing “Finally // Beautiful Stranger” on my HD-600 or HE-560 I did not need any software gain boost, and would only set the Macbook system volume at 60% with the Hi-mDAC hardware volume buttons maxed out. With Camilla Cabello “Living Proof” or Taylor Swift “Lover”, and Zac Brown Band “My Old Man” I didn’t need more than 75% system volume with the Hi-mDAC. Even at 100% it did not break up, and I turned it back down to comfortable levels at 50-70% system volume.
With the album “Kool Cats” by Guinea Pig, as stated before, the string bass through the HD-600 and HE-560 was tight and punchy, and the volume was moderately loud and very clean at 100% system volume. I only needed to set the system volume to 75-80% to enjoy it. Hitting the SoundSource “boost” button could make this album play quite loud and clean, at volumes significantly louder than the built-in headphone jack (maybe even 6-7 dB louder, vs 3-4 dB louder with no software gain boost).
And the bass impact did not fade as the volumes got too high with the HD-600 or HE-560, like I only noticed with the NXEars Basso 4-driver IEM at extreme volumes. On the Kool Cats album with gain “boost”, the Hi-mDAC could play just as loud and clean as the DACport HD in high gain mode at max volume. But, I still did not typically need to use the SoundSource boost button, and only cranked it up to test its capabilities.
As a comparison, I tried matching sound levels with HD-600 on the Hi-mDAC vs DACport HD with their hardware volume controls at max. If I set the Hi-mDAC to 60% system volume with no gain boost, it played at the same level as the DACport HD in low-gain mode at 100% system volume. If I cranked the Hi-mDAC up to 100% with the SoundSource “boost” turned on, then Hi-mDAC was as loud as the DACport HD in high gain at max volume.
Without SoundSource, the DACport always had more power on tap than the Hi-mDAC, so I do recommend SoundSource if you plan to use desktop-class headphones at high volumes with the Hi-mDAC AND you find that the standard gain is not enough. It’s obvious that the Hi-mDAC would have more power available if it had just had a gain switch (would like to see that, but they designed this for IEM and portable gear).
At extremely high volume levels on the Hi-mDAC, it can drive ANY IEM to such high volumes that you would NEVER EVER reach that point on any typical day. In most cases I will never use more than 30-50% of the Hi-mDAC’s power with an IEM. When listening to a more demanding headphone like an HD-600 or HE-560 I would use anywhere from 30-100% of the system volume.
What surprised me was the compromise that many of my portable over-the-ear headphones offered me, with them not sounding as good as any of the IEM nor as good as the more demanding high-power full-size headphones. Granted, two of the three were Bluetooth portable headphone and were tuned for wireless. The Cerene dB are wired only and a little better than the V-MODA, and I listened to the entire Eric Clapton album tonight with them on the Hi-mDAC. But it’s still a more bassy compromise vs the Audeze Mobius that were a brighter headphone with flatter bass (so I preferred them with the DACport HD or via Bluetooth).
Very little of what I heard with these over-the-ear portable headphones was the Hi-mDAC’s fault, although the CEntrance Cerene dB do slightly improve with some program material when used with a CEntrance amp, maybe because they are from the same company. I really wish that I had the new Sennheiser Momentum Wireless to try with this amp, but maybe someday. It was too much trouble to dig out my retired Shure 840, V-MODA XS, or V-MODA M-80, but I’m thinking that those might all be a better match for the Hi-mDAC.
NOISE - I could not hear any hiss with any of the IEM used (but my ears are almost 58 years old).
PHONE COMPATIBILITY - The Hi-mDAC is compatible with the Apple USB Camera Connection Kit (CCK) to use with my iPhone 11 Pro Max. It also works quite well with the Penon Audio Silver Braided USB-C to Lightning Decoder cable. I have a similar Penon Audio decoder cable in a micro-USB to Lightning version, and that works directly with the BlueDAC and DACportable with an iPhone. The CEntrance HiFi-M8 V1 is great with a Phone, and no CCK is needed, but it’s really more of a transportable amp due to its size and weight (can’t dangle from the iPhone by a cable like Hi-mDAC). They say the Hi-mDAC works with Android devices, but I don’t own one to test that.
The Hi-mDAC volume is controlled by the iPhone system volume just like with the Macbook, and the Hi-mDAC always starts off at less than full volume on the software side and hardware buttons, so you don’t blow away your ears when you plug in (same with Macbook pro). So, after you plug it in you have a choice to turn up the system volume, or you can leave the system volume alone and turn up the volume with the hardware volume buttons first.
It seems like there are a large number of steps when pushing the physical volume buttons, and you must either press the volume up button like 20 times to get a noticeable increase in volume, or I found it faster to press-and-hold the volume button until it hit the level that I wanted and then I would let go of the button.
The iPhone > Hi-mDAC > W80 or Opera IEM was very enjoyable, for example, and sounded like an upgrade from the Apple brand Lightning to Headphone adapter (which itself is actually pretty nice). When I first tried the Hi-mDAC with iPhone before burn-in, with the CCK and a fresh out of the box NXEars Basso, it sounded a bit bright. But after everything was burned in, I tried the Hi-mDAC with the Penon Audio cable and iPhone, and this was significantly better sounding than the first time. I have not had a chance to revisit the original Apple CCK, having access to only the Penon decoder cable right now, but it should sound the same.
The Hi-mDAC is powered completely via the lightning port, and is one of the cheapest hi-res DAC/amps to work with the Apple CCK. The fact that I cannot use some of its nearest competitors, my $150 DACport HD or $99 Audioengine D3, with an iPhone had been disappointing, but now we have the solution. I do not have a Dragonfly to test, but if I recall correctly the one that would best compare with the Hi-mDAC is 2x as expensive.
The more expensive DACportable and BlueDAC from CEntrance do offer iPhone compatibility at 2-3x the price, size, and weight. However, those CEntrance amps also have noticeably more power for full-size demanding headphones on an iPhone (HE-560), due to their internal battery power supply. But not only are they larger and heavier so you can’t dangle them off the end of a cable on your iPhone, but you have to regularly charge their batteries while the Hi-mDAC does not need to be charged. You can put a Phone on a wireless charger while listening to music with the Hi-mDAC and it will run forever.
CONCLUSION - Overall I really liked the Nuprime Audio Hi-mDAC, and give it two thumbs up. I would like to get one of these for my son and a couple of friends, not just for myself.
It’s a versatile and very affordable DAC/amp that works with computers and mobile devices as well. It’s earned the “m” moniker in front of DAC, and the “Hi” for Hi-resolution. It’s very neutral and uncolored with a good soundstage, and has more than enough power for IEM and portable headphones, but it surprised me with how well it also handled some full-size headphones. Again, it’s not as powerful as a desktop amp, but more than enough to use them with a computer or phone that can’t drive them as well.
In my case, I would completely skip all my portable headphones and just use my HE-560, HD-600, or IEM with it. It’s small enough that it becomes part of your full size headphone cable when connected to a computer, and it grips the USB-C plug and the headphone plug tightly enough that it can hang off the side of your desk with a headphone plugged in and not lose the connection on either side. It’s like having a digital headphone cable.
I would also just carry the Hi-mDAC and the 6" Penon Audio Lightning-USB cable with me when I want to listen to my iPhone, instead of using the Apple Lightning-Headphone adapter or camera connection kit.
I did not test the optical S/PDIF output, but it seems like a great way to integrate one’s computer with a home theater system, or to use a computer with a high-end DAC that doesn’t have as good of a USB input. If I get a chance to test this later I will add it to the second post in this thread. Same thing if I ever dig up my V-MODA XS or M-80 to try with it, as well as other headphones. I needed to post my review now, but I will have it for a bit longer to give more impressions and comparisons over time.
Jason Lim at Nuprime Audio graciously sent me a Nuprime Audio Hi-mDAC to review in advance of the release during the CanJam NYC weekend of February 15-16, 2020. This will replace the older, larger, and discontinued uDSD USB DAC - being much smaller and compatible with mobile devices as well, while still offering high quality analog and digital outputs. I have not heard the uDSD, so I cannot compare them. I did compare to some competitor’s products.
https://nuprimeaudio.com/product/hi-mdac/?v=7516fd43adaa
GENERAL INFO: MSRP $129. Measuring 5.0cm x 2.2cm x 1.2cm.
SPECS: Hi-mDAC utilizes a new chip, CS43131 from Cirrus Logic, together with a NuPrime customized low power USB communication chip.
PCM decoding up to 32-bit /384Khz.
Increased hi-fi DSD playback rate from DSD128 to DSD256.
Integrated GND-centered, Class H headphone driver.
Output level up to 2 VRMS into 600 Ω headphones (can be used as a pre-amp to feed another amp).
Frequency Response 20-20Khz +/- 0.5 dB.
Evolved performance: THD+N 0.005% at 1Khz.
S/N Ration >100 dB (20-20Khz A-weighted).
Ports: USB-C, Combination 3.5mm analog audio output and 3.5mm S/PDIF converter (PCM192 and DoP64).
Output power:
30 mW per channel into 32 ohm load
5 mW per channel into 600 ohm load

FIT AND FINISH: The top of the Hi-mDAC has a silver tone mirror finish with the company logo. On one side are volume up and volume down buttons, with no gaps or spaces between the buttons and side of the case. The other 5 sides are all a brushed aluminum finish. There is a very fine seam where the top and bottom half of the CNC machine case come together, and the edges are flush.
The volume buttons have nice feedback, and don’t so much as click when depressed and they bounce back when released. The Hi-mDAC included USB-A to USB-C cable feels like it’s high quality, with a nice soft-to-the-touch woven fabric jacket, and not some thin cheap rubbery coating. Plugging in the USB-C cable results in a click and firm/tight engagement. The same is felt when plugging a headphone into the 3.5mm jack.
MUSIC SELECTIONS - I chose a variety of lossless music including but not limited to the following - Jack Johnson “On and On”, Dianna Krall “Live in Paris”, Ed Sheeran “X Wembley Edition”, Martin Garrix “2019 Remixed”, Camilla Cabello “Romance”, Amanda Palmer “Performs the Popular Hits of Radiohead with her Magical Ukulele”, Eric Clapton and BB King “Riding with the King”, Post Malone “beerbongs & bentleys”, Taylor Swift “Reputation”, Zac Brown Band “Welcome Home”, Chris Jones “Roadhouses and Automobiles”, Billie Eilish “When we all go to Sleep, Where do we Go?” and “don’t smile at me”, Dierks Bently “Riser”, Eric Church “Chief”, Zara Larsson “So Good”, Pink Floyd “DSOTM”, Blueport Nuforce Jazz Sampler, and Timothy Seelig “Rutter: Requiem & Five Anthems”.
GEAR USED - 2014 Macbook Pro 15” on Mojave with Nuprime Audio Hi-mDAC $129, CEntrance DACport HD $149, BlueDAC $399 (similar sound to DACport HD and DACportable), iPhone 11 Pro Max with lightning cable adapter, and iPhone directly into Hi-mDAC using a USB-C to lightning data cable from Penon Audio $39. NXEars Sonata, Basso and Opera balanced armature IEMs. Westone W1, W40 and W80 balanced armature IEM. V-Moda Crossfade Wireless II, Audeze Mobius, and CEntrance Cerene dB portable over-the-ear headphones. Sennheiser HD-600 with APureSound V3 cable with 3.5mm plug, and HiFiMan HE-560 with a Moon-Audio 3.5mm Silver Dragon cable.
SOFTWARE - iTunes 12.9.5.5, Tidal app for OS X, Rogue Amoeba SoundSource. SoundSource offers additional gain via “boost” button to drive HD-600 and HE-560 louder than Mac OS X would normally allow, without distortion. It also offer a distortion free EQ if needed, and allows you to select the system source plus a different DAC/source for several different audio apps.
Nuprime suggests setting the system volume level to 100% for the best dynamic range, and then using the hardware volume buttons to adjust the listening volume, and I agree. But if you are lazy, being able to use the system volume and Macbook volume buttons to control the music in a pinch is very convenient. Certainly more convenient than with the DACport HD which disables the system volume buttons on the keyboard. When you first plug in the Hi-mDAC, both the system volume and hardware volume levels will be reduced, so that you don’t get blasted too loudly with music when you hit play.
SoundSource lets me adjust the system volume via a slider, even when a DAC/amp like DACport HD disables the Macbook volume buttons. In order to do an apple-to-apples comparison of volume settings between the Hi-mDAC and other DAC/amps, I had to max out all their hardware volumes and use SoundSource app to adjust the system volume and then note the percent of volume that they required to volume match. The Hi-mDAC has a lot of steps in the volume control, too many to easily count the steps and say “I was on step 24 of 64 while the blah blah DAC/amp had the volume knob at 20%” etc. I don’t even know how many steps it has, but it’s a lot.

SOUND AND TONE - The Hi-mDAC has a very neutral, flat, and transparent or uncolored sound signature. I would not call it a warm sound signature, but it’s not cold either. In comparison to the CEntrance DACport HD and BlueDAC or HiFiMan R2R2000, I would say the R2R2000 sounds the warmest and most lush, and the CEntrance products are slightly warmer and punchier than the Hi-mDAC but still leaning towards neutral and transparent.
The sound and tone depends on the program material and headphones that you chose to listen with, so I tried to mix and match various amps + headphones + music, which gave me an overwhelming combination of choices to report on; but I’ll try to do my best to break it down for you here. I think that next time I will discuss all the aspects of sound with each IEM or headphone as a whole, instead of breaking it down by bass, midrange, treble, etc.
BASS - With any of the IEM that I tested, the mDAC has strong bass delivery, which is deeply extended. The bass is controlled, tight, and fast as well. It has no peaks or troughs that I noticed. But in comparison to the DACport HD, I’d say that the DACport has a little warmer and punchier sounding bass, which depending on the headphones that could be better or worse.
As above, I use Rogue Amoeba’s “SoundSource” app on my Macbook to direct sound to whichever device I wish to listen, and it also includes some preset EQ choices, like bass booster, treble reducer, etc. Using the bass booster setting with the Hi-mDAC and IEMs works very well, and and with the gain boosted with SoundSource it does not drive the amp into clipping with any of my IEM or expensive full-size headphones at normal to very loud volume levels.
But I found that my over-the-ear high-efficiency lower-cost portable headphones are more easily driven to distortion at extreme volumes, unlike the full size desktop-class headphones. But all of my critical listening was done with NO EQ unless specifically testing the amp’s ability to handle extra bass without clipping.
While playing random songs in Tidal with the NXEars 8-driver Opera IEM, Eric Church’s song “Over when it’s Over” came up, and the weight and foundation of the kick bass drum really took me by surprise - I could almost feel it in the room with me. With the same tracks, I switched to the CEntrance Dacport HD where the bass impact increased and it sounded slightly warmer - the Opera are less picky about the amp than the Sonata or Basso IEM from NXEars, and so the bass didn’t change as much with a change in amp.
I then listened to Timothy Seelig, Rutter Requiem III: Pie Jesu, and the bass of the pipe organ reaches to subterranean depths with the Hi-mDAC, with all of the IEM and even with the HD-600. While the pipe organ bass is deep and extended with HD-600, it’s bass impact on some other genres of music doesn’t impact quite as hard as it does with a more powerful amp with higher voltage swing. But with the album “Kool Cats” by Guinea Pig, the string bass with the HD-600 was very tight and punchy, and the Hi-mDAC volume with HD-600 was moderately loud and very clean all the way up to 100% system volume.
The following is almost more of a review of the over the ear portable headphones than the Hi-mDAC, but I wanted to talk about how it drives a variety of portable or transportable full-size headphones that I have readily available. I usually do not amplify these headphones, and a couple of them I usually only use via bluetooth.
The V-MODA Crossfade Wireless II is known as a bassy headphone, and with the Hi-mDAC at just 50% volume their bass is massive with the string bass on Guinea Pig “Kool Cats”. The V-MODA bass was a little too much with both the mDAC and DACport HD. With Rutter Requiem Pie Jesu the pipe organ has power and weight, but the HD-600 still had better bass quality and control than the V-MODA with the Hi-mDAC.
I usually prefer to use the V-MODA with old classic rock recordings that didn’t have a lot bass in the mastering, or to use at low volumes where I would otherwise might want a loudness control. I also have not used them in wired-mode more than 2-3 times and usually am using them with Bluetooth. But, when playing the Guardians of the Galaxy soundtrack and a variety of Led Zeppelin recordings via Hi-mDAC and Tidal lossless, they had good bass balance, while the DACport HD had similar bass but pushed the midrange too forward.
The CEntrance Cerene dB closed headphone was a better match for the Hi-mDAC than the V-MODA. Before burn-in the Cerene dB were a bass heavy (almost sloppy-bass) headphone, but after they were fully burned-in their bass had become tighter and more controlled. The bass still hits very hard and is a fun headphone with the Hi-mDAC and all my classic rock, electronic, jazz, and classical.
But with songs like Post Malone “Paranoid” and “Psycho” the Cerene dB bass overpowered the midrange and treble on the Hi-mDAC. Switching to the DACport HD from the same company brought the midrange up to a level closer to the bass, but at the expense of soundstage. Just switching to Eric Clapton “Unplugged Remastered” put the Hi-mDAC on top again, with a more balanced tight bass and bigger soundstage.
My Grado HF-2 had strong bass and good control with the Hi-mDAC, but the Grado HF-2 also needs to be your “low volume quiet listening” headphone with the Hi-mDAC, due to exacerbating the Grado’s inherent wall of sound and grainy treble. At low volumes there is no need for bass boost or a loudness control with the HF-2, and I was really enjoying them at 25-30% system volume (with buttons maxed out), but cringing at very high volume which occurs at only 50% system volume.
I pretty much only ever use my HF-2 with my $3000 Eddie Current ZDT amplifier which is so silky smooth and refined in the highs that I can crank up the Grados without fatigue. But, it’s a headphone that I often don’t like at high volumes, and none of my portable amps improve that (the TTVJ portable Millet Hybrid was the best with Grados, and I miss it but sold it due to the tube rush with IEM).
The last headphone I tried with the Hi-mDAC was the HiFiMan HE-560 with Moon-Audio Silver Dragon 3.5mm cable. This is a headphone that I thought likes an amp with a lot of current, and thrives on my 2 watt Schitt Audio Magni 3 amp, so I almost didn’t bother trying it. Even the manufacturer didn’t expect it to be a good match. I was really taken by surprise when the Hi-mDAC can drive the 560 to good/moderate listening volume levels, with tight, fast, and strong bass and everything else)! It didn’t seem like it was running out of current or straining at all.
This combo is even better than the HD600, and it also responds well when the SoundSource “boost” gain mode is enabled. Even with gain “boost” turned on at the same time as bass boost mode (was just as a test), the Hi-mDAC did not give up and barely got warm. I listened the rest of the time with normal gain and NO EQ, and was very impressed with string bass and pipe organ, as well as electronic music from Steven Garrix and Infected Mushroom. I liked the Hi-mDAC and HE-560 combination with just about every song that I listened to, and this was my favorite full-size headphone combination. Only a few times did I want to use the gain “boost” button.
MIDRANGE - The midrange is true and clean, transparent and uncolored, and does not add to or remove anything from the music. Any changes in sound were due to the sound characteristics of the IEM or headphones used, not due to the amp. It’s like “wire with gain”.
For example, when I was doing my NXEars review over the past week, I found that the DACport HD could make the midrange presence a little overwhelming with the 4-driver NXEars IEM or my V-MODA at very high volumes. But the Hi-mDAC did not give me this problem and the midrange was very smooth and natural, even with headphones that usually have a U-shaped frequency response.
The Hi-mDAC midrange was open and transparent with any IEM or full-size headphone I used, even the V-MODA (which had a little too much mid bloom with the DACport HD). With the Cerene dB and Hi-mDAC the midrange was not recessed, so much as the bass was sometimes boosted in relation to the midrange. But I thought the Hi-mDAC did a good job with the Cerene dB on instruments in “Kool Cats” such as saxophone and trombone (un-like with Post Malone).
With Eric Clapton “Before You Accuse Me” on the “Un-Plugged Remastered” album, the clapping to the music sounded natural and real, and not like rain on a metal roof like you get with some gear. Some people have complained that the HE-560 has a U-shaped frequency response with recessed midrange, but I didn't think the midrange was missing on these with the Hi-mDAC.
TREBLE - The treble is usually sparkly and shimmery, maybe too much so in the first 2 days before burn-in, but it settled down quite nicely after about 4 days of music through it.
After burn-in I found the treble to be very detailed and crisp, transparent and smooth, without any veil or grain (if not listening to a Grado which need tubes). Sibilance is not exacerbated with the Hi-mDAC either. It brings out the best of the treble qualities in all of my Westone IEM, Sennheiser HD-600, HiFiMan HE-560. With the Cerene dB and V-Moda Crossfade Wireless II (wired mode) I wished for a little more treble.
My Audeze Mobius sometimes felt a little bright with the Hi-mDAC at higher volumes, but I hear this a lot on the Mobius with music on my iPhone with them. I mostly use the Mobius to watch movies on my MacBook or TV via bluetooth, where it excels at 3D sound with movie and games. The DACport HD had smoother treble with the Mobius and HF-2, but the midrange became too forward so I preferred the Hi-mDAC overall, just at lower volumes with these portable headphones.
The NXEars IEM worked best with Hi-mDAC when using the upgraded pure single crystal 6N copper cable and small tips/deep insertion. Otherwise, with the silver plated copper cable they’d sound a little bright on the Hi-mDAC vs with the other amps I tried. Because of how well the Hi-mDAC works with the HE-560 on a silver cable, I’d say this was an “IEM on the wrong cable” issue, not an amp issue.
IMAGING AND SOUNDSTAGE - The Hi-mDAC has good soundstage and imaging, and it sounds effortless and transparent in it’s presentation. I felt that it sounded a little more open and spacious, and less intimate sounding than the CEntrance products (or R2R2000). I preferred the Hi-mDAC with my Westone W1, W40, and W80 IEM, which gave the Westone a little bigger soundstage than with the CEntrance DAC/amps.
The NXEars IEM all seem to have a little bigger soundstage regardless of amp, and paired a little better with the punchier CEntrance amps. However, the NXEars still sounded very good with the Hi-mDAC, and this is the amp that I used exclusively for the first 2-3 days of my NXEars IEM review that I posted earlier this week. This combination frequently gave me some out of head cues while listening, and a couple of times I looked around to see what was making a sound only to realize it was in the recording.
The HD-600 and HE-560 full-size desktop headphones also sounded a bit more open and spacious with the Hi-mDAC than my CEntrance amps, despite the extra power reserves of the CEntrance amps. Note - I do think the balanced 2.5mm output of my BlueDAC is more open sounding with better separation than the 3.5mm jack I was using.
POWER OUTPUT AND SYNERGY with different headphones - Gear synergy is important, and different IEM and headphones can change the sound characteristics, depending on how they interact with the Hi-mDAC’s output impedance. I do not know the output impedance, but If you don’t like the Hi-mDAC with one IEM or headphone, I say try another before giving up.
How well a headphone paired with the Hi-mDAC also depended on the source material, and while I would not listen to Post Malone “Beerbongs & Bentleys” with the Cerene dB and Hi-mDAC at high volumes, the pairing sounded great with Eric Clapton “Unplugged Remastered” or Guinea Pig “Kool Cats” at any volume.
Listening fatigue can also play a roll, and after listening to music with the Cerene dB for 2 hours straight, when I switched to Taylor Swift “Reputation” I thought that the bass was much better controlled than with something like Post Malone “Beerbongs & Bentleys” but it sounded like all the treble had disappeared. I had to take a long break after this. This did not happen with long listening sessions with my IEM or the HD-600 and HE-560, but my portable over-the-ear headphones contributed to fatigue much faster than the others.
I thought the Hi-mDAC had great synergy with Westone W1, W40 and W80. It also paired well with my V-Moda Crossfade Wireless II and Cerene dB with classic rock (or if playing anything at low volumes). In comparison to its nearest competitor, the DACport HD is a warmer and more powerful amp, and I found that the NXEars IEM sometimes had a little better synergy with the DACport HD (it was a toss up with the 4-driver Basso).
Synergy with my HD-600 and HE-560 was very good with the Hi-mDAC. I really enjoyed the combination and I only occasionally needed to max out the system volume and hardware volume buttons to get the desired volume, especially with some classical music like Rutter Requiem, or some jazz and new age tracks. If I needed more gain I could use SoundSource’s Gain “Boost” button to get more system volume with these quiet recordings.
With Jack Johnson playing “Taylor” or “Dreams be Dreams”, or Halsey playing “Finally // Beautiful Stranger” on my HD-600 or HE-560 I did not need any software gain boost, and would only set the Macbook system volume at 60% with the Hi-mDAC hardware volume buttons maxed out. With Camilla Cabello “Living Proof” or Taylor Swift “Lover”, and Zac Brown Band “My Old Man” I didn’t need more than 75% system volume with the Hi-mDAC. Even at 100% it did not break up, and I turned it back down to comfortable levels at 50-70% system volume.
With the album “Kool Cats” by Guinea Pig, as stated before, the string bass through the HD-600 and HE-560 was tight and punchy, and the volume was moderately loud and very clean at 100% system volume. I only needed to set the system volume to 75-80% to enjoy it. Hitting the SoundSource “boost” button could make this album play quite loud and clean, at volumes significantly louder than the built-in headphone jack (maybe even 6-7 dB louder, vs 3-4 dB louder with no software gain boost).
And the bass impact did not fade as the volumes got too high with the HD-600 or HE-560, like I only noticed with the NXEars Basso 4-driver IEM at extreme volumes. On the Kool Cats album with gain “boost”, the Hi-mDAC could play just as loud and clean as the DACport HD in high gain mode at max volume. But, I still did not typically need to use the SoundSource boost button, and only cranked it up to test its capabilities.
As a comparison, I tried matching sound levels with HD-600 on the Hi-mDAC vs DACport HD with their hardware volume controls at max. If I set the Hi-mDAC to 60% system volume with no gain boost, it played at the same level as the DACport HD in low-gain mode at 100% system volume. If I cranked the Hi-mDAC up to 100% with the SoundSource “boost” turned on, then Hi-mDAC was as loud as the DACport HD in high gain at max volume.
Without SoundSource, the DACport always had more power on tap than the Hi-mDAC, so I do recommend SoundSource if you plan to use desktop-class headphones at high volumes with the Hi-mDAC AND you find that the standard gain is not enough. It’s obvious that the Hi-mDAC would have more power available if it had just had a gain switch (would like to see that, but they designed this for IEM and portable gear).
At extremely high volume levels on the Hi-mDAC, it can drive ANY IEM to such high volumes that you would NEVER EVER reach that point on any typical day. In most cases I will never use more than 30-50% of the Hi-mDAC’s power with an IEM. When listening to a more demanding headphone like an HD-600 or HE-560 I would use anywhere from 30-100% of the system volume.
What surprised me was the compromise that many of my portable over-the-ear headphones offered me, with them not sounding as good as any of the IEM nor as good as the more demanding high-power full-size headphones. Granted, two of the three were Bluetooth portable headphone and were tuned for wireless. The Cerene dB are wired only and a little better than the V-MODA, and I listened to the entire Eric Clapton album tonight with them on the Hi-mDAC. But it’s still a more bassy compromise vs the Audeze Mobius that were a brighter headphone with flatter bass (so I preferred them with the DACport HD or via Bluetooth).
Very little of what I heard with these over-the-ear portable headphones was the Hi-mDAC’s fault, although the CEntrance Cerene dB do slightly improve with some program material when used with a CEntrance amp, maybe because they are from the same company. I really wish that I had the new Sennheiser Momentum Wireless to try with this amp, but maybe someday. It was too much trouble to dig out my retired Shure 840, V-MODA XS, or V-MODA M-80, but I’m thinking that those might all be a better match for the Hi-mDAC.
NOISE - I could not hear any hiss with any of the IEM used (but my ears are almost 58 years old).
PHONE COMPATIBILITY - The Hi-mDAC is compatible with the Apple USB Camera Connection Kit (CCK) to use with my iPhone 11 Pro Max. It also works quite well with the Penon Audio Silver Braided USB-C to Lightning Decoder cable. I have a similar Penon Audio decoder cable in a micro-USB to Lightning version, and that works directly with the BlueDAC and DACportable with an iPhone. The CEntrance HiFi-M8 V1 is great with a Phone, and no CCK is needed, but it’s really more of a transportable amp due to its size and weight (can’t dangle from the iPhone by a cable like Hi-mDAC). They say the Hi-mDAC works with Android devices, but I don’t own one to test that.
The Hi-mDAC volume is controlled by the iPhone system volume just like with the Macbook, and the Hi-mDAC always starts off at less than full volume on the software side and hardware buttons, so you don’t blow away your ears when you plug in (same with Macbook pro). So, after you plug it in you have a choice to turn up the system volume, or you can leave the system volume alone and turn up the volume with the hardware volume buttons first.
It seems like there are a large number of steps when pushing the physical volume buttons, and you must either press the volume up button like 20 times to get a noticeable increase in volume, or I found it faster to press-and-hold the volume button until it hit the level that I wanted and then I would let go of the button.
The iPhone > Hi-mDAC > W80 or Opera IEM was very enjoyable, for example, and sounded like an upgrade from the Apple brand Lightning to Headphone adapter (which itself is actually pretty nice). When I first tried the Hi-mDAC with iPhone before burn-in, with the CCK and a fresh out of the box NXEars Basso, it sounded a bit bright. But after everything was burned in, I tried the Hi-mDAC with the Penon Audio cable and iPhone, and this was significantly better sounding than the first time. I have not had a chance to revisit the original Apple CCK, having access to only the Penon decoder cable right now, but it should sound the same.
The Hi-mDAC is powered completely via the lightning port, and is one of the cheapest hi-res DAC/amps to work with the Apple CCK. The fact that I cannot use some of its nearest competitors, my $150 DACport HD or $99 Audioengine D3, with an iPhone had been disappointing, but now we have the solution. I do not have a Dragonfly to test, but if I recall correctly the one that would best compare with the Hi-mDAC is 2x as expensive.
The more expensive DACportable and BlueDAC from CEntrance do offer iPhone compatibility at 2-3x the price, size, and weight. However, those CEntrance amps also have noticeably more power for full-size demanding headphones on an iPhone (HE-560), due to their internal battery power supply. But not only are they larger and heavier so you can’t dangle them off the end of a cable on your iPhone, but you have to regularly charge their batteries while the Hi-mDAC does not need to be charged. You can put a Phone on a wireless charger while listening to music with the Hi-mDAC and it will run forever.
CONCLUSION - Overall I really liked the Nuprime Audio Hi-mDAC, and give it two thumbs up. I would like to get one of these for my son and a couple of friends, not just for myself.
It’s a versatile and very affordable DAC/amp that works with computers and mobile devices as well. It’s earned the “m” moniker in front of DAC, and the “Hi” for Hi-resolution. It’s very neutral and uncolored with a good soundstage, and has more than enough power for IEM and portable headphones, but it surprised me with how well it also handled some full-size headphones. Again, it’s not as powerful as a desktop amp, but more than enough to use them with a computer or phone that can’t drive them as well.
In my case, I would completely skip all my portable headphones and just use my HE-560, HD-600, or IEM with it. It’s small enough that it becomes part of your full size headphone cable when connected to a computer, and it grips the USB-C plug and the headphone plug tightly enough that it can hang off the side of your desk with a headphone plugged in and not lose the connection on either side. It’s like having a digital headphone cable.
I would also just carry the Hi-mDAC and the 6" Penon Audio Lightning-USB cable with me when I want to listen to my iPhone, instead of using the Apple Lightning-Headphone adapter or camera connection kit.
I did not test the optical S/PDIF output, but it seems like a great way to integrate one’s computer with a home theater system, or to use a computer with a high-end DAC that doesn’t have as good of a USB input. If I get a chance to test this later I will add it to the second post in this thread. Same thing if I ever dig up my V-MODA XS or M-80 to try with it, as well as other headphones. I needed to post my review now, but I will have it for a bit longer to give more impressions and comparisons over time.