Kiwi Ears Allegro Mini

A beautifully simple usb-c headphone dac amp

The Kiwi Ears Allegro Mini is a small, lightweight USB-C DAC and headphone amplifier designed for those who prioritize portability and convenience. Priced under $25, it competes with other ultra-portable DAC/amps while promising impressive audio performance for its size. Does the Allegro Mini live up to its claims? Let’s find out.

Unboxing

The Allegro Mini comes in minimalist packaging:

The back of the box showing some support and contact information:

Opening the box you see the Mini nicely displayed with a small user guide:

This no-frills approach keeps costs down but provides everything you need to get started.

Build Quality

The Allegro Mini is impressively compact, weighing just a few grams and small enough to fit into any pocket or stay attached to your earphones without adding bulk. The casing is made of durable plastic with a matte finish, giving it a clean, unobtrusive aesthetic.

The device features a single USB-C input and both a 3.5mm and 4.4mm output depending on which side of the mini you look at:

[PHOTO with iPhone]

Features

The Allegro Mini supports PCM up to 32-bit/384kHz and native DSD up to DSD128, ensuring it can handle high-resolution files without issue.

Sound Quality

Despite its small size, the Kiwi Ears Allegro Mini punches well above its weight in terms of sound quality with its Neutral response. Here’s a breakdown:

Bass

The Allegro Mini delivers tight, well-controlled bass with a slight emphasis that adds warmth without becoming overpowering. Tracks like Billie Eilish’s “You Should See Me in a Crown” highlight its ability to provide a solid low-end foundation without muddiness.

Midrange

Vocals and instruments are rendered with clarity and natural warmth. Listening to Norah Jones’ “Don’t Know Why” showcases the Allegro Mini’s ability to maintain a balanced and engaging midrange, making it suitable for vocal-centric music.

Treble

The high frequencies are crisp and detailed, avoiding harshness or sibilance. Classical pieces like Vivaldi’s “Spring” are reproduced with clarity, allowing string instruments to shine.

Soundstage and Imaging

While the soundstage is understandably narrower than larger more powerful DAC/amps, the Allegro Mini provides good spatial separation for its size. Imaging is precise, making it easy to identify individual instruments in complex tracks like *Pink Floyd’s “Money.”

Specifications and Measurements

• DAC Chip: Built-in DAC/amp chip for consistent audio decoding.
• Output Power:
  • 3.5mm: L+R ≥ 30mW+30mW (32Ω, THD+N < 1%)
  • 4.4mm: Slightly higher output for balanced configurations.
• THD+N: < 0.004% (32Ω load, A-weighted).
• SNR: ≥ 114dB (32Ω load, A-weighted).
• Frequency Response: ±0.2dB (20Hz-20kHz).
• Input: USB-C
• Output: Choice of 3.5mm or 4.4mm depending on the model.
• Compatibility: Works with most USB-C devices, including Android smartphones, tablets, and computers.

Practial Measurements and Comparisons

Why I am calling this a ‘practical measurement’ section?

DAC should be transparent windows into your audio collection

You will often see reviews on head-fi (and other websites) talking about the subjective differences between different headphone DAC amps, one having a better bass response or another focusing on the midrange while a third might give you a more detailed treble and this was certainly the case in this market as recent as 3 years ago. And especially was the case at both the cheaper end of the market (as the technology was not as matured) but it can also for the very high end where manufacturers want to distinguish their devices with unique sound signature.

But in my opinion, DAC and Amplifiers should not change (by design) the sound signature, though obviously some implementations are better than others and some implementations (like Tube amps) will deliberately ‘colour’ your sound (like a stained-glass window). Older cheaper designs would also affect the extremes of your sound (the sub-bass) or poor filter implementations (near 20,000Hz) - maybe like glass that has ‘blurry’ or ‘frosted’ edges but then crystal clear in the middle.

I believe the best DAC and Amplifiers should be perfectly transparent and let your music be ‘seen’ perfectly clear by your headphones and IEMS (and Speakers), unless you choose some EQ to your preference.

Measurements of an old DAC compared to a modern one

Few manufacturers previously would publish their measurements but as an example I did find during my recent review of the FiiO KA15 some earlier measurements of the FiiO K3, for comparison and the difference I think perfectly illustrate the point that the industry has moved on. Below is the FiiO DAC K3 from 2019 compared to the latest KA15:

K3 - roll off at extremes	KA15 - perfectly transparent

While from 20-20,000Hz the K3 was a mostly flat it does roll off while a modern DAC will (should) be transparently ‘flat’.

Selection of a Headphone for ‘Practical Measurement’

Rather than compare DAC Amp SINAD charts, I thought for this review it might be more fun to see how well does this DAC Amp (and a few other portable DAC amps) perform when driving a real headphone to loud ‘90+ dbSPL’ volumes and then measure the output from that the headphone to see if it is still transparent. This is to remove most of that typical uncertainty that I read when people just read DAC or Amplifier measurements (i.e. ‘but how will it perform with my XXXX headphone’ ).

So over at AudioScienceReview Amir has been putting together an interesting graph of how hard it is to drive any headphone that he has measured, and it is becoming a very extensive and interesting list covering most of the ’normal’ headphones (and some very expensive ‘high end’ headphones). Here is the latest version of that chart:

For those interested here is the source of this version of the list is from his latest: DCA Noire X review

So I thought I should use a headphone from the bottom end of this chart as a good ’test’ of these DACs, so I picked the Hifiman Sundara (as I am about to publish a review of that headphone). So here is that section of the list zoomed:

As you can hopefully see I thought the Hifiman Sundara was in the good ‘challenging’ part of this chart. So lets see how the Allegro does. But first I thought I should measure the Sundara with various Headphone DACs to compare if there is any ’tonality’ differences:

Hifiman Sundara FR with various DACs

So in this test I measured the Sundara using my KB501X softear pinna and a 711 clone coupler and I decided to ‘volume level’ the output measured (as close as I could) with the various DAC Amps:

As you can hopefully see each one of the devices used produced the same result (i.e. they were all transparent at 90+ dbSPL). I even started using my Macbook Pro own headphone jack, then the Apple usb-c, and then I followed up with both the single ended and then the balanced output of various dongles.

Here a photo of the dongles (including the Allegro) that I used in this measurement (though I didn’t measure the Qudelik 4K and the FiiO KA17 in this particular comparison):

So in this photo the ones I used are Fosi Audio DS2, FiiO KA15, iBasso Jr Macaron, Kiwi Ears Allegro and the Kiwi Ears Allegro Mini on the right-hand side of this photo and is the smallest of these devices.

So the point of this is each of these devices can drive a ‘hard to drive’ headphone but the question is still what ‘headroom’ they leave for that ‘high dynamic range’ track or for applying EQ filters (often needing an extra 10dbSPL).

To capture and understand this I used my Macbook Pro to ‘record’ what volume was needed to drive each device to this ‘volume matched’ level(through with the Macaron I had to use Macaron own volume buttons).

I believe you should always have some headroom when driving headphones so having more volume available, the better but which of these devices has ’enough’ for your use-case (on this relatively hard to drive headphone), so low volume is better:

I think it’s pretty impressive that all these devices could drive the Sundara to a pretty loud 90+ dbSPL, but what does each cost:

So the KA15 is considerable more expensive but does have a little more power, a screen and PEQ capabilities via a companion application.

The Allegro Mini is slightly more powerful than the Apple USB-C dongle, and it benefits are the conveniences of having both a 3.5mm and 4.4mm and its super compact size so is a good choice for most headphones but from the Sundara downwards in that graph I presented earlier it will get more challenging from a power perspective.

The iBasso Jr Macaron, the Kiwi Ears Allegro and the Fosi Audio DS2 also provide excellent powerful audio. So, as you will see in their individual reviews it a more personal choice of what design suits you. But, the Kiwi Ears Allego Mini makes an excellent choice with it excellent convenient design and ability to drive a good selection of your headphones you own, especially the ones you would be happy to use with a ‘mobile device’.

Given that all these devices are “transparent” with a relatively ‘hard to drive’ headphone at 90+ dbSPL we are at a golden age for ‘pragmatically’ price portable audio devices.

So, here is a comparison of various published specifications for these devices:

Rating

I have given the Allegro Mini a pragmatic rating of 4 stars. I love the concept and the ability to easily use either 3.5mm or 4.4mm from such a tiny device. But it is a pity that the 4.4mm does not have any more power than the 3.5mm output. At this price, the Mini does a reasonable good job with its power, but it is to be expected that the Allegro Mini does not have the power for more demanding headphones.

Conclusion

The Kiwi Ears Allegro Mini is an impressive tiny DAC/amp that offers excellent sound quality for its size and price.

If portability and ease of use are your priorities, the Allegro Mini is a great companion for your smartphone especially if you want you a 4.4mm balance cable with your smartphone. It should work well with all IEMs and most efficient headphones. With its reliable performance and attractive price, it’s a solid addition to Kiwi Ears’ lineup.