Campfire Audio IO Review: Little Andromeda

Campfire Audio IO Review: Little Andromeda

It would be most likely that you have heard about Campfire Audio if looking for good earphones or IEMs – most likely the Andromeda. Though the price tag on those is not so wallet-friendly, yes? Most of the popular Campfire IEMs were quite heavily shifted to the top tier flagship models like Andromeda and Vega, which they have also started to focus on entry models. We previously covered the youngest sibling from the Campfire family, the Comet. While Comet achieves high cost-effectiveness and usability, Campfire launched an upper model, IO, for those who are willing to get a little more serious about music. IO is also the successor of Nova which is now discontinued. It is now time to jump into the review and see how IO sounds and performs against Nova.




Campfire Audio finally went through some revamp with their packaging and I am happy about it. There are lots that do not pay much attention (or not at all), which is very reasonable. But I believe better packaging and boxing do matter when talking about premium IEMs. The size of the new packaging still goes for a reasonably small box but roughly twice the bigger than the old ones. Once you remove the CA sticker on the rear of the box, the outer packaging would unfold and reveal the inner box which includes all the belongings. I very much enjoy this new packaging as they are beautifully designed inside out and gives a feeling as if you are unboxing a present.


Other than the earpieces, it includes 1 set of 3.5mm stock cable, 1 leather case, 3 pairs of earpiece pouch, 5 pairs of Final Audio eartips, 3 pairs of CA eartips, 3 pairs of CA foam tips, 1 CA Lapel pin, and a cleaning tool. CA used to provide only 1 pair of earpiece pouch before, but it seems like they have realized the demand for it and started to throw in an extra 2 pairs – which I appreciate a lot. The lather case is also newly designed to have the same color as the earpiece. The size also got slightly larger for better convenience when storing with custom cables.




As shown, this “mechanical-looking” appearance has been Campfire Audio’s signature design from the get-go. The earpiece is made of machined aluminum and sports an edgy look, though the edges are slightly rounded as well as the inner side forming a fairly ergonomic shape. Not the best in terms of comfort or compatibility, but the fit is not bothering at least. Though users with smaller outer ears will have problems fitting these to their ears as the earpieces are still a bit chunky and edgy.


IO uses 2BA drivers per side – each working as a woofer and a tweeter. Both drivers are incorporated with T.A.E.C. (Tuned Acoustic Expansion Chamber), which is a specifically designed inner structure that sits in front of the drivers and takes a major role in creating their signature sound. The nozzles are made of stainless steel and separated into 2 bores. Another thing to note is that the shape of the nozzle has changed. The nozzles are visibly longer than the old ones which give deeper fit and better isolation. The earpieces are detachable and use custom-made MMCX sockets that are compatible with typical ones yet inforced in durability.




The stock 3.5mm cable went through some changes too. First the shielding. The previous silver-plated Litz cable had a transparent silver look which looked good, but vulnerable to discoloration and stains. The new version has a smoky grey jacket that solves such problems as well as being even softer. Metal memory wires are gone too and replaced with a simple ear hook design.  



Sound impression – Ultra lows / Sub-bass

IO shows a mildly w-shaped sound signature with a small emphasis on the mids. Ultra lows are mediocre, but it manages to deliver enough depth and weight to the sound. Considerably good for a 2BA setup. Bass shows a meaty and high-density thud, striking fast and decaying relatively slower which makes the lows feel full and natural without lagging behind the beat. While the bass creates quite a deep and dark atmosphere, the area for spreading the bass reverbs is well controlled and energetic without getting loosen.


Reverbs are soft and relaxed, resulting in the overall bass quantity to be similar to most IEMs with a slightly v-shaped signature. It is somewhat easy for full BA IEMs (especially those with fewer drivers) to sound dry or lack liveliness, but IO’s bass show much liveliness and moisture like a tightly controlled dynamic driver. Overall the bass is up to par with the quality, even without regarding the driver setup. Not to a game-changing degree, but most people would be able to easily enjoy in both quantity and quality.



Sound impression – Mids / Imaging

The thickness on the mids is just around neutral and works well with both male and female vocals. Comparative to lows and highs, mids put more weight on the airiness rather than density. Not only this presentation blows in lots of air into the sound, but it also allows vocals to sound more spatial and stable. Since that, IO keeps the vocals quite flat and very stable throughout the midrange without noticeable dips, spikes, or sibilances. IO’s sound is extra sensitive to the fitting, so I suggest trying a variety of eartips as the sound may cause hollowness or spikes if your fitting is not secured enough.


Another characteristic of IO is its positional aspect. While we use terms as close/neutral/laid back for explaining the relative position of the vocals, though vocals on IO feel as if they are spreading out from more of the rear side which eventually reaches out to the front. This creates a spatial, lively presentation that keeps the vocals absolutely fatigue-free. Thanks to these two characteristics, delicate reverbs and airiness, IO’s mids do not feel stuffy despite the overall brightness slightly tipping over to the darker side.


Therefore, those who dig 3D effects or the ones that are used to multi-driver-ish sound should find IO’s presentation quite pleasing. However, those that are extra sensitive or demand raw/original presentation may find it bothering – especially if you do not like the sounds from full-BA or hybrid IEMs. If you are used to IEM-generated staging, it is likely not a problem. Although I am pretty sensitive to artificial sound, I found the presentation to be fun as it is not like the timbre has been completely abandoned or completely went over the head.



Sound impression – Highs / etc.

Highs are another part that supplements some freshness and shine to the sound while keeping the sound comfy and relatively dark. Highs are crisp and analytical, being capable of grasping the small sparkles and layering clearly separated from each other. The lower trebles take a slight dip and then continues to shine – this will not kill the treble details but rather prevents the highs from getting overpowered or harsh. The thickness is on the slimmer side but has enough body to it.  Highs also have a super-fast response speed and don’t leave many reverbs or residues, keeping the atmosphere clean and organized. I am in fact very pleased to see such detailed and crisp treble quality for a 2BA IEM in this price range. It feels solid and high in clarity without getting too close in the face or feeling rigid. Highs make sure to keep its presence clear and prominent, with a lively and tasty timbre but not to the point of falling behind in neutrality.


Staging is quite on the larger side – not gigantic, but to say the least, the 2BA setup does not seem to be limiting IO from presenting a dynamic, wide, and full headroom. It is important to point out that this presentation is formed with accuracy, so the wider staging was not achieved by throwing in a bunch of resonance. IO shows just the appropriate amount of resonance to blow in musicality and smooth flow to the sound while maintaining a clean enough background. Imaging is also correctly presented, doing a fine job locating the instruments to their intended places.



Compared to Nova (2BA)

I always had a soft spot for Nova. Its smooth and fatigue-free sound was its charm that I also appreciated, yet it has not gained much attention from the users and got discontinued fast. Anywho, IO is Nova’s new successor so this would be a good comparison. Nova presented a rather slow-tempo, old-school sound, while IO is up for a more engaging and trendier sound reinforced with vibrancy and brightness.


IO also presents mids in a more uplifting, refreshing, and airy manner. The resonances are slightly lesser than Nova yet IO preserves plenty amount of reverbs and quantity, making the sound just full as Nova but even better in clarity. Though Nova would not be put down to the grave since it still holds its ground with its own charm. Nova is still very desirable for those who dig a Westone-like sound signature with a harder bass texture, but if you are looking for more upper frequency details and sparkles, IO would definitely be a superior choice.



Eartip / Cable suggestions

Recommended eartips for IO would be either Final E-Type (the ones included as accessories) or Acoustune AET07. This would be more about personal preference, though I would suggest AET07 eartips as the best matching as it provides a wider, unaltered sound presentation. It is also crispier and higher in transparency, so the upper frequency details would be opened up even more. The bass still keeps its tightness with a good amount of quantity. E-type eartips would be a better deal if you want the sound darker or bassier, though unless that I would suggest giving a try with the AET08. The best cable selection with an affordable price would be Satin Audio Gaia and I am confident about it. Satin Audio has been recommending the IO-Gaia combo even before I got my IO in hands, and those two sure do match well. Gaia provides better clarity, staging, and tone throughout the sound as well as delivering a richer bass response. 




I have seen some mixed impressions for IO, yet my experience has been positive all the way since the first time meeting this IEM during an exhibition. Campfire Audio has done a good job boiling down the Andromeda into a 2BA version, forming an exciting sound signature yet consisting of enough neutrality. Not ideal for those desiring the most plain or unaltered sound, but for a fun, toned up fidelity gear, I would say this is one of the fairest choices you could make. Built upon Campfire’s signature sound, IO is a cost-effective performer that I would actively recommend as it holds a powerful, hackish place in the lineup. Keep your eyes over here if you are looking for a sub $300 IEM with an all-rounder, fun sound signature. 



Thanks to CA for providing IO for an honest feedback/review.

I am not affiliated with CA and none of my words were modded or asked to be changed.

Campfire Audio IO
Fun, smooth, and analytical sound
Great set of accessories
Andromeda-like signature with 3D staging
High price-performance ratio
Not meant for those who seek highly unaltered, raw presentation
Timbre has slight coloration