Headphoneus Supremus
Pros: Build quality
Comfortable fit
Well balanced sound; very good detail and timbre.
Cons: qdc proprietary 2-pin cable
Review - qdc Fusion

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Website – qdc

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  • Driver units: 4 balanced armature drivers + 1 dynamic driver; 3 sound channels, 3 crossover
  • Sensitivity: 106dB SPL/mW
  • Frequency response: 10Hz-20000Hz
  • Impedance: 18Ω
  • Noise isolation: 26dB

The Fusion is packed in a same large cardboard box as the VX and other qdc models. This time the outer box is gold-brown colored while the inner box is the same black box with a strong magnetic closure seal. The earphones are arranged on the right side with the cable attached and wrapped inside, while the left side holds the accessories and usual paperwork. For accessories you get the same as on the VX flagship, four pairs of single ear tips and three pairs of dual flange tips, a leather like cubic case in similar turquoise color to match the Fusion earphones, cleaning tool and adapters. The single tips have been changed for softer ones compared to those included on the reviewed Anole VX and do work better. The case has strong magnetic clasping closure and same inner section to hold the cable.


This is the universal version of the Fusion (Fusion-S), and like the other qdc universal fit models, it arrives in a standard fixed color option. Even so, the selected color theme is quite attractive with translucent shells and turquoise faceplates with a marble like touch on them. The shape is very similar to the Anole VX and looks like a minimized size of it, probably due the less amount of drivers and elements inside the Fusion. Build quality is as good as the VX flagship using same high quality of materials and flawless finish. With a same custom-like fit the shells are made of high grade acrylic and do look solid enough. The faceplates have different designs printed on them, ‘qdc’ writing on the right side and a fancy ‘F’ for Fusion on the left.

Nozzle quality is top notch as well, all metal, being the main body made of nickel-plated copper and stainless steel grill and the top, all perfectly attached, just as the Anole VX. The nozzle diameter is very standard as well so trying different ear tips should be easy.

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As can be seen through the clear shells, the dynamic driver is placed towards the back of the shell while the four balanced armature units are packed together closer to the nozzle part. There are three acoustic tubes inside, one for the dynamic and one for each of the dual BA units – on a closer look it is possible to spot the three bores underneath the nozzle grill. Being a hybrid model with a dynamic unit, there is a very small hole on back side of the shells for acoustic vent.

The shape may look a compact version of the Anole VX, but still a universal custom-like shape. Even so, in practice the fit feels more ‘universal’ like, as being smaller provides a more relaxed fit. I personally found the VX to be the closest to CIEM, and while the Fusion has the same contact points to ear it is less tight. The depth of the nozzle is the same and sits very ergonomically making a so comfortable and natural fit for a universal in-ear model. The included single flange ear tips have been changed from the ones arriving with the VX that I tried, not just with the colored cores to identify the size but are softer and easier to get a proper seal with them. In fact, and despite the limited array of tips, these included ones are good enough; even after a bit of tip rolling, there no major changes or improvements in sound, so pretty much kept using these for the sake of the review. The isolation is actually very good and the small vent does not seem to have any noticeable impact in this regard. Isolation is very good for what universal in-ear can get, just below the VX, maybe because the more compact shells.

The 2-pin cable connection is the usual own qdc type, which is different than the standard 0.78mm options. This make it more proprietary, but there are already easy to find on many cable makers. The 2-pin sockets are placed above the earpieces main body and the plugs are well covered on the cable side as well. The angled plugs attach tightly and are well relieved to minimize the unnecessary strain.

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The cable itself looks of good quality, as what should be expected at this price range. The wire this time is of silver plated copper and consists of four strands tightly twisted on the lower half from the plug to y-split which then divide into two strands (softly twisted) for each side. From the clear cable sheathing it is possible to see there is a good amount of wire inside. The cable is terminated in a standard 3.5mm plug with a solid metal cover also applied on the y-split.

Sound Quality

The Fusion is the first hybrid model from qdc, which may be the beginning of a new line of in-ear monitors along with their pure multiple BA options. Priced at what could be considered as upper mid-tier earphone, the Fusion has a five drivers’ setup that consists of four balanced armature small drivers and a single dynamic driver. Logically, the dynamic driver is set for the low frequencies, while the BA units, which are actually two dual BA drivers, are selected for mids and highs.

In spite of the hybrid setup, the Fusion is tuned different than most of hybrid IEMs I’ve tried in where the dynamic part was used to bring a large and powerful bass response, usually resulting in at least a slight v-shaped signature or in occasions a warmer and more bass oriented. The Fusion instead offers a more linear response, with very little emphasis on particular frequency and still well balanced and full textured sound. The hybrid setup is very clear here; the dynamic driver performance is obvious and together with the multiple BA parts it turns out to be a very accurate and detailed IEM.

The low-end is well weighted, nothing overemphasized but still above than just neutral. There is excellent equal balance from sub to mid bass, with quantities that are rarely missing and full texture on each notes. It is tight, very controlled and precise. There is no mid-bass lift that can be noticed and the transition to lower midrange is kept very clean. Speed is well achieved as well, matching the high speed of the balanced armature drivers for very good coherence; however, the lows to mids/highs separation is easy to perceive. The extension is fairly good, and while missing a fuller rumble, the bass shows particularly very good depth and separation.

The midrange continues the similar linearity as the low-end, a bit more forward thanks to the balanced armature nature, still very neutral within the whole presentation. There is not real warmth that arrives from the dynamic counterpart leaving a very clean and open midrange. Low and high midrange are very equal in weight and texture feels rather natural and very smooth; tonality is neither cold nor warm, suiting a variety of music genres without shining at anything specific. Vocals while very detailed and well positioned can still sound a bit dry; price and quality aside, it is a different presentation from the sweet and more emotional sound on the Anole VX flagship. On the other hand, instruments’ separation is neat and precise. Where the midrange on Fusion does stand out is in detail and resolution and transparency. It is also effortless and articulated and very airy without having an extra upper mid tilt.

Treble is a bit elevated on its whole range and still maintains the good balance with lows and mids, so nothing too forward or too bright. Excellent control too and nothing aggressive or hot. While it doesn’t show any particular peak, it is not totally smooth as there is a little sharpness. The extension is very decent for the dual BA, not top tier levels but good reach for the under $1K range; it is quite effortless and very detailed to capable to catch the little nuances.

The soundstage may not be the main attraction on the Fusion, though it is well rounded. While not narrow or intimate, it is more limited in not having that out of the head large width, though there is very good depth and even decent height for an in-ear set. The Fusion does surprise with a very natural timbre and coherence, not just for a hybrid model.


iBasso IT04
(3BA & 1D)

The IT04 is more lively, v-shaped and warmer tuned compared to the Fusion. It is also more colored and less transparent next to the more linear, neutral sound of the Fusion. With a 10mm graphene dynamic for lows, the IT04 is just much powerful and expressive with greater mid-bass kick and well pronounced sub-bass. Quantities are obviously larger on the IT04, and not next to the Fusion but also to other hybrids of the list. The Fusion is more about higher quality, also faster and much tighter, better in separation and dynamics. On the midrange, the IT04 is thicker on low-midrange putting more weight and density to instruments and more body to male vocals; upper-midrange is thinner and more energetic. In contrast, the Fusion is more linear and very even on the whole midrange, with less coloration but more resolution, cleaner and higher detail. The IT04 has more low-treble energy, while the Fusion brings greater treble balance, control and refinement – something to be expected for the price difference. Soundstage is wider on the IT04, at least out of its balanced sound; the Fusion has more depth and a bit more height and sounds more spacious overall.

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DK-3001 Pro (4BA & 1D)

Next hybrid is the new DK-3001 Pro, and also a 5-driver model like the upper 4001 and the QDC Fusion. Drivers’ size and types are different from the Fusion to DK-3001 Pro, but both having a 4 armatures, 2 for mids and 2 for highs, and a dedicated dynamic for lows. Both hybrid IEMs do present a very even sound from bass, midrange and treble, though they differ in their tonality and texture. The DK-3001 Pro is thick and smoother, whereas the Fusion is linear and cleaner. Fusion is more extended in the bass, very effortless and very dynamic, where the 3001 Pro is more focused on the mid-bass; not too much in quantities, especially if compared to the above IT04, but it is slower and more dense. Both are very similar in midrange balance, though sometimes the DK-3001 Pro can be perceived as a bit vocals centered with its sweeter texture. Treble is very smooth on the 3001 Pro, even to point of being ‘safe’ sounding and more limited in its extension, while the Fusion is brighter and a bit sharp, as mentioned above. Soundstage is similar in width, and then Fusion has more depth, with more air and 3D presentation.

final B1 (1BA & 1D)

Last of the hybrids for comparison will be the very new B1 from final. Despite the just two drivers used on the final B1, the sound is as competitive as multiple hybrid IEMs. Price difference is smaller than the above hybrids, and depending on the region can go from $100 to $200 more for the QDC Fusion. Sound wise, the B1 is warmer with a more pronounced bass and extra emphasis on the mid-bass; the Fusion is logically more reserved but has more extension, and bit more speed and control. Midrange is more forward and richer on the B1, and best suited for vocals among all the hybrids mentioned here, with a very sweet presentation, while the Fusion is drier but cleaner and more detailed, airy and with better separation. Treble focus on the B1 is put on the lower treble with smoother, and bit roll-off at the upper extension. The Fusion is brighter and a tad sharper; sibilance is sometimes present on the B1, while the Fusion is still more forgiving.

Custom Art Fibae 3 (3BA)

If all the above hybrids are warmer next to the Fusion, it is the opposite with the Fibae 3. The Fibae 3 is very, very detail oriented with its bright signature. The bass is super fast in the best BA type, and then limited in extension and sheer power and quantity; very tight, quick in attack and also in decay. The Fusion is more extended, more dynamic and realistic in bass texture and depth with fuller notes; speed is high, but not as fast the BA unit of the Fibae 3. In the midrange, the Fusion is very equally weighted between low and up mids, and the Fibae 3 has a bit more emphasis on the upper mids; both are similarly neutral never sounding distant. The Fibae 3 is still more liquid while the Fusion more textured. Treble quantities are more abundant on the Fibae and puts the all the micro details very forward, with greater treble energy; the Fusion is nothing shy either, just more leveled and natural.
Worth noting that the Fibae 3 can be picky or at least source depending to sound to its best, whereas the Fusion is more forgiving.

Hifiman RE2000 Silver (Dynamic – Topology tech.)

The Silver version of the RE2000 may retail at $1500, but the current $800 price makes it worth mentioning vs. the Fusion. Again, different driver types here, hybrid setup against the single dynamic driver with its topology coating tech.
I only listened briefly to the RE2000, so impressions may not be too accurate. The RE2000 is similarly neutral and well balanced, though compared to the Fusion, the RE2000 is just slightly v-shaped. Soundstage dimensions are close, the RE2000 having a little more width and the Fusion better depth and almost identical height. Bass is more weighty on the Fusion while the RE2000 may show a little more mid-bass punch and more shy sub-bass. Midrange is very clean on both, with the RE2000 being a bit thinner and giving little more priority to vocals (female) and not sibilance free. The Fusion is smoother and more rounded. Highs extension goes for the RE2000, but is also more aggressive on the lower treble, and while the Fusion is also bright it seems more linear on its whole response.


The Fusion might be the first of a hybrid in-ear series from qdc, but it already shows great capabilities mixing both dynamic and balanced armature drivers tech. It is not tuned for impactful bass, sizzling highs or widest stage, but clearly brings great dynamics, very accurate and detailed sound with a natural timbre.
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