Campfire Audio IO In-Ear Monitor Headphones - Official Thread

I have the Andromedas and am a big fan. I love the sparkle that they have. I love the treble too. The whole sound signature is spot on for me and my tastes. They are just such a great set of iems. I haven’t tried any other campfire stuff. I would have liked to get a pair of Solaris myself but I went in another direction instead.

I like the whole experience you get with Campfire and their customer service has been great.


Thanks to the community preview program I was able to evaluate the Campfire Audio Io and the Polaris V2. I’m catching up on posting some of my impressions after a crazy few weeks at work.

My general take is this: These are better than I expected.

I suppose I made the mistake of looking at the frequency response measurements for the Io before listening to them. This IEM has generated its fair share of criticism with its extreme upper midrange cut. But I think it’s also important to consider the context of where the Io fits price-wise. I know that for many people $299 is the most they’d ever consider spending on an IEM, but within this hobby I’d consider the Io closer to an entry level product - especially when considering the rest of the Campfire Audio lineup. With that said, I always find that with IEMs at this price point, they struggle to do two things right, namely treble response and bass extension. They can sound good, but often at the cost of one or both of those aspects.

The Io somehow manages to absolutely nail both of those. Usually I find that the treble rises too early, causing the splash to sound slightly compressed and occasionally the tonal focus can even be a bit harsh as well. And then almost every single IEM I’ve tried under the Andromeda has substantial treble roll-off above 10khz. Not only does the Io rise at the perfect spot for treble splash without causing sibilance, harshness, or compressed sound, it doesn’t roll off until beyond 12khz. This causes it to have possibly the best treble extension I’ve ever heard at this price point, and I can think of a number of IEMs three times the price that the Io outperforms in the treble. It also has possibly the best soundstage I’ve ever heard at this price point as well. Something about Campfire’s T.E.A.C system is doing good things here.

Similarly, the bass is well-controlled, extends deep, and doesn’t bleed into the midrange the way some of the more ‘V’ shaped IEMs do. While this is less ideal for commute purposes with ambient low-frequency drone sounds often overpowering bass presence, in more optimal environments this is exceptional. On balance this is a fairly neutral IEM with a slight upward tilt and treble focus.

Now to the bad stuff. The upper midrange cut between 2-3khz is probably where the dual BA drivers cross over, leaving a substantial piece of information significantly subdued. This causes female vocals to sound a bit dry and hollow. But 2-3khz is also right where the ear canal and ear drum resonance amplification occurs (at least according to this), and so how bothersome this cut is will depend on the amount of canal + drum amplification. Or in other words, this will depend on the listener. Without getting too much into the whole objective/subjective thing, there’s room for differences in appreciation that are grounded in physiological differences between people, and we need to remember that ideal targets are based on averages, not specific ears. Without question, the 2-3khz dip is a bad thing, but I’m not finding it nearly as bad as I expected, and that’s likely to do with A) how much my brain expects the ear canal + drum amplification and B) how much my ear canal + drum specifically amplifies 2-3khz (for all headphones/IEMs).

In a perfect world we’d be able to measure all the different parts of our ears to identify where the amplification occurs and to what degree, and then EQ things accordingly, but unfortunately we’ll have to settle on averages for now and do it by ear. The bottom line for the Io is that while it has one major flaw, it does many other things beyond my expectations for this price point. And for me, those outweigh the primary issue. I’d even go as far as to say I prefer the Campfire Io over the Polaris V2, and many other more expensive IEMs. The Io reminds me most of the Campfire Jupiter, which had a similar upper midrange cut. But remember, that’s also a much more expensive IEM. So in a sense, this builds out Campfire Audio’s more neutral and less ‘V’ shaped lineup - something they’ve needed to do for some time.

You can check out my video review here


Nice review and video! You’re getting pretty good at this stuff.