Raptgo Hook-X Review: Hooked on a Feeling
September 6, 2022 Andrew Cheng

I’ve said it before, and I’ll say it again: planar magnetic driven IEMs are the future. Sure, this driver type had a rocky start with the iSine series from Audeze, as well as the P1 from Tin HiFi. But in recent times, planar IEMs have gotten much better, while also going down in price!

However, the Raptgo Hook-X we have here…isn’t particularly affordable. Retailing at $239 (about RM1,075) on Linsoul, this IEM is one of the more expensive planars released recently, especially if you compare it to the $100 7Hz Salnotes Dioko we previously reviewed.

That being said, I do think the Hook-X is worth its asking price. Not only is there effort in the product’s packaging and overall presentation, the Hook-X also sounds fantastic – to my ears, anyway.

What It Is

If you haven’t heard of Raptgo before….you’re not alone. Although the hard shell carrying case that comes with the Hook-X proudly states “since 2019,” the brand hasn’t exactly released any standout products. That is, until this particular IEM.

As Linsoul’s catalogue of Raptgo products show, the brand previously released two balanced armature IEMs, as well as a set of TWS earphones. The Hook-X is not only the brand’s first planar IEM, it’s also the first of its kind to make use of a piezoelectric driver.

That’s right, the Hook-X’s 14.2mm planar magnetic driver is paired with a bone-conduction driver. The planar driver is said to provide a strong bass response, while the piezoelectric driver handles the highs.

Besides that, the Hook-X is an open-back IEM too, which (in theory) allows for a more airy sound signature with less pressure and congestion in the soundstage. You definitely don’t get as much isolation as fully-closed earphones because of this, but it’s still quite decent – similar to that of “semi-open” IEMs. Sound leakage is also a non-issue with the Hook-X: there’s only a faint leakage, and that’s only if you put your ear right up to the perforated shell of the IEM.

The packaging of the Raptgo Hook-X is quite an elaborate one, though at this price point, you really shouldn’t expect any less. Aside from the earphones themselves, you get the aforementioned hard shell carrying case, three sets of tips in three different sizes, and a braided cable with a black and green colour scheme to match the colourway of the IEM itself.

It’s also worth noting that the cable features a hot-swappable jack that gives you the choice of terminating in the standard 3.5mm or balanced 2.5mm and 4.4mm jacks. The cable is, however, rather prone to microphonics, not to mention the fact that it tangles incredibly easily too.

One other thing: the three sets of tips that come with the Hook-X? Well, they only give you the illusion of choice, as there doesn’t seem to be any sonic or physical difference between them. I just stuck with the light green ones as they match the aesthetics of the Hook-X.

How Does It Sound?

The combination of a planar and piezoelectric driver seems to work for the Hook-X, as it sounds incredibly fun and energetic. It has a warm-ish tonality with fast, impactful bass, a forward mid-range, and clear highs. There’s simply a lot to love with the Hook-X, though it isn’t without its pitfalls. The sound signature is quite U-shaped with an emphasis in the lows and highs, but that doesn’t necessarily mean the mid-range is lacking.


Bass response of the Hook-X is, in my opinion, the standout quality of the IEM. While the sub-bass doesn’t reach all that low, the impact it provides is tight and incredibly controlled. The same can be said about the mid-bass, where you’ll also immediately notice the speed of the bass – fast and full of energy.

There’s also a “rawness” to the bass that gives the Hook-X an almost…analogue presentation. It’s definitely got to do with the warmer tonality and speed of the bass, though I suspect the open-back design of the IEM plays a role here as well, though I can’t say for certain.


I wouldn’t go as far as to say that the mids of the Hook-X are disappointing, but it feels that way as the other sections of its frequency range are that good. Note weight of both instruments and vocals, for example, can sound a bit thin on the Hook-X.

The forwardness of vocals makes up for this a tad bit, though I do wish there was a bit more body to what is the most prevalent part of a music track. There’s also a slight graininess to the mids of the Hook-X, which isn’t ideal, even if it does add to the analogue quality provided by the bass.

But it’s not all bad though, as vocals are still laid-back and sound pleasant with a hint of warmth from the bass. This especially benefits female vocals and keep them from sounding sharp, despite the thinner presentation.


Treble of the Hook-X is smooth and well-controlled, just like its bass response. The above average extension provides plenty of air and crisp to snares and cymbals. Clarity isn’t the best due to the presence of grain, but detail retrieval is still quite impressive.

Without a doubt the Hook-X’s bone-conducting piezoelectric driver provides good control and detail to the treble. However, on the flip side, it does make the treble sound a tad artificial as well.


The horizontal width of the Hook-X’s soundstage is quite expansive – the open-back design might be at play here – but vertical depth is limited. Interestingly, the soundstage does open up a fair bit when connected to more powerful sources.

Is It Worth It?

It’s often a gamble to mix different driver types and expect good sound quality in an IEM. But the combination of the planar and piezoelectric drivers of the Raptgo Hook-X just…works. The open-back design also alleviates listening fatigue, allowing me to enjoy this planar IEM for longer listening sessions at a time.

But the Hook-X is far from perfect with the presence of grain throughout the frequency range, along with mids that are a bit too thin for my liking. Granted, the addictive bass and smooth treble more than make up for these shortcomings.

Moving forward, expect even more brands to release planar IEMs at various price points. If you want to hear for yourself just how good a planar IEM can be, the affordable 7Hz Salnotes Dioko is worth a gander. But if you have the budget and prefer something a bit more fun-sounding, the Hook-X will not disappoint.

Li Jin Soh contributed to this review.