Headphone Review: Heir Audio 3.Ai

Heir Audio | In-Ear Monitor | $ 299.99

Heir Audio is a new brand here on iFans, and in general as well. They started specializing in custom IEMs specifically. They have recently went to the universal world creating universal models of their two lower-tier IEMs, the 3.A and 4.A. The universal models are called the 3.Ai and 4.Ai respectively. The 3 offering a fun sound while the 4 offers more neutrality*. Bass heavy, treble heavy, fun. The 3.Ai represents big bass done right.

*I haven’t heard the 4.Ai, it’s claimed to be more neutral.

In the Box

  • Heir Audio 3.Ai
  • Large Carrying Case
  • Silicone Tips (3 Blue-Barred Filterable Hybrids: S/M/L; 3 Red Hybrid: S/M/L; Dual Flange: S/M/L
  • IEM Cleaning Tool
  • Bands
The 3.Ai come with a fare amount of accessories; including 2 bands to help keep your DAC connected to your AMP!


The design of the 3.Ai is not customizeable like their custom line of IEMs. That said, they will use similar materials, and the only differences will be the shade of the wood (no two woods are the exact same color). The faceplates are composed of an absolutely beautiful amboyna burl. This piece of wood looks very exotic and natural at the same time. The rest of the housing is a dark translucent violet. These just look absolutely gorgeous in any light.

The amboyna burl is pretty.

Design: ★★★★★


When I first put the 3.Ai in my ears, my thoughts were expressed through Twitter as such:

In my mind, no truer words have been said thus far. The signature of the 3.Ai is a V-shaped signature. The bass is pounding with authoritative impact that is nice and tight. The midrange has great clarity, but more importantly stunning vocals while the highs shine bright and beautifully. I stand by my words that it’s big bass done right. That said, the headphones are driven by 3 drivers, a tiny one for the mids, a tiny one for the highs, and a huge one for the bass that is bigger than the mid and high driver combined.

Heir Audio also includes a blue hybrid tip that has a bar running through it that allows you to hold a piece of acoustic filter between the tip and the nozzle to adjust the signature of the 3.Ai (and 4.Ai). No filters are included though; but knowing this can be an option is always a good thing.


Such a large bass driver leads to big bass. I can’t stress that word enough. The texture is absolutely fluid and euphoric in just about every aspect. They have a thinner body to them, but slam extremely hard with prowess and strength. A punch is well perceived to complete the entire package. Textures seem to come straight from thin air in absolute clarity. It’s well controlled, and never really intrudes upon anything or becomes undone. It’s big bass done right.

Bass: ★★★★★


The midrange is crafted in a delicate fashion, but very well for a V-shaped signature. The vocals are the biggest strength here, right next to the rumbling bass. The vocals get a deep lushness that is extremely inviting while the sweetness comes through with strong energy. The end result is wide dynamics in the vocals and instrumentals alike. The clarity in the upper-midrange is clear as a bell. In the lower mids, some clarity is lost however as this is the area of the V. Most, if not all details are there despite the lost of clarity down low.

Mids: ★★★★½


The high end is not lost with the 3.Ai either. It’s not perfect, but does very well on most aspects. They sparkle clearly and provide much energy into the high end. They are never sibilant, or harsh, in any way either; like the bass, very well controlled. Separation and clarity are tuned very nicely. Detailing is present throughout. The lower highs are strong and snaps extend long and far with a good flare. The lower highs, however, are more recessed and lack some presence.

Highs: ★★★★½

Audio: ★★★★½


The Heir Audio 3.Ai come inside a gigantic case; actually, this case doubles as the box they come in. That said, this case is not the best for travel, so I’d recommend you find something smaller and more portable. The large case, however, is very protective and looks a lot like an OtterBox. Heir Audio also does have plans for a smaller case in the future that will be much more friendly on the go.

The case is humungous… A little large for portability though.

With all that said, the housings are made out of acrylic. This is a hard-plastic-like compound that feels very firm and tough and is used in Heir’s custom IEMs as well. It’s smooth to the touch and has a very quality feel to it. The faceplate is also very smooth and feels like it’s coated with some acrylic as well.

The housings are beautiful in their own right, but the acrylic seems strong. They do have dual bores split sound output (one bore for highs and mids, one for lows I assume).

Inside each housing is a pair of small holes. These holes are the contacts for the removeable cable. The cable contact itself isn’t recessed though, which can cause some of the contacts to bend easier (which can cause damage to the actual headphones). Heir Audio offers two types of cables, their generic cable (that is included) and their Mangus 1 cable (not included).

The connectors on the 3.Ai is not recessed, which does make it easier to warp the pins on the cable.

That said, the cable can be upgradeable and replaced if it were to break. The cable is in the shape of a double helix and feels great in the hand. It’s flexible and doesn’t tangle while it has a strength in numbers.

The included cable is very strong.

The headphone jack on these is also of good quality. The jack itself is large and strong with a nice strain relief sticking out of it. The strain relief is flexible but also strong. The jack itself is also coated in gold.

The headphone jack is among the best out there.

Build: ★★★★½


Heir Audio’s 3.Ai are universal (or generic) models of their custom 3.A model. That said, they have a shape that is particularly similar to a custom IEM’s shape. They did shave a lot from the body to make it much more comfortable though. The housings are light and compact which make them very comfortable to wear for hours. The memory wire can help comfort-wise and isn’t too short by any means. Heir Audio includes 9 pairs of tips in 3 sets (3 pairs per set) to ensure a proper fit.

9 pairs of tips are included to ensure a good fit.

Comfort: ★★★★★


Heir Audio offers a beautiful overall package with the 3.Ai. The design uses really beautiful, yet professional, wood amboyna burl that is exotic in its own way. They are just about built to perfection while the comfort is top notch. More importantly, however, the sound quality is very bass heavy, but very well controlled. They have merged both quantity and quality together to create a very fun sounding IEM.

Value: ★★★★★

Final Thoughts

Heir Audio puts their blood, sweat, and tears into each and every IEM they make. The 3.Ai is a testament to that statement. I was blown away (by bass) when I first put them in, and they continue to give me shivers and make my hair stand. It’s just that crazy.

I’d like to thank Brennan for the product sample

Overall Score


Heir Audio 3.Ai

† All prices are in US currency.
This review was written by the iFans.com Review Team. Cumulative scores are rounded to the nearest half or full star.
This accessory, product, or app was received as a sample. Thanks Brennan for the product sample.
Post a response / What do you think?