FiR Audio M4


– 64 Audio Tia Trio –

These are very similar IEMs in terms of build quality and driver configuration (4-driver hybrid vs 3-driver hybrid) and so I initially expected the M4 to be similar to the Trio -I know, I am not always the most logical person- but they differ more than I had expected. The Trio are darker sounding, giving them a more laid-back feel compared to the M4. The M4 push details forward more clearly and yet present it in a way that feels more open and natural. Not that the Trio have the occlusion effect, their own tubeless design and built in Apex pressure release system is also very effective, but it seems like FiR Audio have managed to improve on it with the M4. The bass of the Trio feels a bit looser and woollier compared to the bass of the M4 and the M4 seem to dig a little deeper, keeping it tighter and retrieving more texture and detail at the same time. The mids of the Trio are perhaps a little warmer, but here I find that they share a similar natural tonality. The treble on the Trio feels a bit more polite and I personally never had any issues with it.

Overall, I think these are both excellent technical performers and the main difference is in their tuning. The Trio are more easy-going, as well as more fun and engaging in my opinion, whereas the M4 are a little more restrained (i.e. good clean fun) and push details more clearly forward. I feel the M4 have the upper hand in pure technical performance, but it can be a bit misleading because of the Trio’s darker signature. With both I have this same sense that the more I listen, the more impressed I am by what they are capable of. If it is between these two, then I think it mostly comes down to personal preferences. I personally prefer a slightly darker signature, so in that case the Trio has the edge, but at the same time I can’t ignore the bass of the M4, it is just too good.

– DITA Dream XLS –

I recently reviewed the Dream XLS and already did a comparison there, but I wanted to include it again based on the longer time I have now spent with the M4. These two IEMs are very different and the M4 are definitely the more energetic ones that bristle with energy. If I compare the two with, for instance, Wolf Alice’s ‘Yuk Foo’, the difference in energy is really noticeable. The Dream XLS are much more subdued in the bass and the treble, although the detail and texture is at a very similar level, the M4 simply push it forward a lot more. The treble of the M4 also has a bit more brightness and there are sparks flying with this track, which is not something that can be said with the Dream XLS. Mids of the Dream XLS are a little fuller and warmer and they are comparatively speaking, more mid-centric than the M4. The level of detail is really close, although as I mentioned it is presented in a different way. Both the IEMs excel at it and you will be hard pressed to find others that can do it quite like this: lots of detail and yet non-fatiguing. Be it with the caveat that, depending on your own treble tolerance, it might be good to roll tips with the M4 and use a relatively smooth source.

Build quality with both is excellent and you really get IEMs that will no doubt last a long time. In terms of fit I think the M4 work a little better for me personally, but I have always liked the fit of Bogdan’s IEMs (I count previous and current models of 64 Audio’s IEMs here too because he was involved in their development). The Dream XLS do have the edge in giving a more luxurious feel and those come with a better stock cable, but they are a bit more expensive as well.



With the M4 FiR Audio have produced a highly versatile set of IEMs that have a fairly uncoloured sound with a well-balanced bit of excitement coming from the bass and treble, while performing at a very high technical level. I always enjoy exploring IEMs and will generally find things I really like about them, but it is rare that I am so consistently impressed by IEMs as with the M4. They work for every type of music I have tried and always perform at the highest level regardless of price. With only a minor caveat concerning the lower treble lift, I can highly recommend a demo.

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