The midrange is the best part of the Phantom. Instruments sound lively and engaging with many genres, and they have very good resolution. However, I found the timbre to be the best trait of the Phantom in this area. It sounds natural and organic in the mid section and certain instruments shine really well. Piano, violin and sax are the ones that come to my mind.
Vocals are also very impressive and definitive with great tonality and range. In fact, they sound just a bit closer than the instruments, making the vocal based music quite enjoyable and satisfying. Mid range also has good balance in terms of weight, note size and definition.
The resolution in this area is another positive part of the Phantom. Transparency, especially in the vocals, is very good as well. So I think it gives the listener good value for money in mids overall.
Although highs are not as impressive as the mids, they still put up a fairly good performance. This is the area that benefits the most from the foam removing mod to be honest. The headphone has more breathing room when you remove the foams, and this results in a much better treble response.
Treble has good definition and resolution together with nice transparency. So I have no complaints from that perspective. However the treble to me doesn’t have the best positioning. I think highs are too close to the stage, and that creates a boxy and congested staging performance.
Other than that the extension could’ve been better but I don’t want to complain too much about it because of the price. The detail retrieval in treble is quite good and highs have good articulation overall.
The technical performance of the Phantom is good as a whole, but there are some minuses here and there, which is totally normal. First of all, the sound-stage width is not impressive and the depth doesn’t provide a better performance either. This is even worse with the stock configuration. When you remove the inside foam pads, the situation betters and there’s more space in sound.
The instrument separation is nice despite the narrowness of the sound-stage, which is good in my opinion. The sense of space and air is not the best of course, and the treble positioning makes it a bit worse. Besides, the tonality of the headphone is really good and the timbre is spot on. This is one of the most important things in headphones in my book, and the Phantom simply nails it.
The vocal and instrument presentation also deserves praise in terms of transparency, resolution and texture. It’s a joy to listen to vocal oriented music with this headphone, and a lot of times I found myself playing Vocal Jazz songs with it.
Phantom has a 47 ohm impedance and 93±3 dB sensitivity. This means it’s not hard to drive it. Several sources, DACs and amps would do the trick. My tests resulted with the same observation. Hugo 2 and Dethonray HA-2 drove it with ease.
If you’re after that certain planar magnetic sound with a reasonable budget, the Thieaudio Phantom is a formidable choice. Just remember to remove the inner foams and bear in mind its small deficiencies in sound in here and there.
In the end, it’s not fair to expect a 1000 $ planar headphone performance from this one. But what you can expect is simply good value for money. I experienced worse sound performances from more expensive gear, so the Phantom is in a very good place in my mind.
So, even though it has some weakness in its sound, I’m putting this into our Best Full Sized Headphones list. Its mid range performance solely deserves this recommendation for this price level. If they somehow can improve certain aspects of this headphone in the future, it would sell like hot cakes.
They can start by removing the foam damps right away!