Tweak and tune
The most significant addition to the FH7’s design is the new filter system, made up of a series of three anodized and colour-coded filters that screw in (very smoothly I must say) to the end of the metal nozzle of each earpiece. I’ll discuss the specifics of the filters and how they work to affect the sound later in this review, but for now it’s enough to say that the addition of filters is a boon to what is already a feature-packed product.
One of the less-noted but equally important benefits of the new filters is the additional 1mm or so of length they add to the FH7’s nozzle. This is not insignificant; the biggest criticism by far of the FH5 was its ultra-shallow fit which, combined with a thicker-than-usual nozzle girth, made it difficult for many to get a good seal, even with larger ear tips. And without a good seal, the sound quality of any IEM degrades considerably.
The extra length and slightly narrower nozzle of the FH7 almost completely correct this issue while retaining much of the noteworthy comfort of the FH5. I say ‘almost’ because the FH7 is still unmistakably a shallow-insert design compared to many other IEMs that tend to reach deeper into the ear canal. I find the FH7 is both more comfortable and more compatible with various ear tips than the FH5, and as such I find it far easier to get a good seal, and is for me the most comfortable IEM I’ve worn to date.
That comfort does vary with your choice of ear tips, however. As with the FH5, I find that JVC’s Spiral Dot tips are both the most comfortable and best sounding choice for the FH7. The longer nozzle of the FH7 does have one drawback with the Spiral Dots, which are themselves a very shallow design – they sit too far back. Spiral Dots use a series of indented dots (hence the name) to smooth out the sound waves coming through the IEM nozzle, but with the FH7, only one row of dots is left exposed.
The solution I found is one that was pioneered by some FH5 users that wanted a deeper insertion – a small rubber O-ring that acts as a spacer. You’ll want an O-ring of about 5.5mm inside diameter and 0.5mm to 0.8mm thickness, and if like me you struggle to source some locally, they’re widely available on Amazon and other online retailers.
With the spacer in place, the Spiral Dot tips have ample breathing room for the ‘dots’ to do their thing. The extra distance between the front of the tip and the nozzle grille also reduces the chance of ear wax finding its way into the sound ports.
If you prefer foam to silicone tips, I recommend you try Dekoni Audio Bulletz (reviewed here), which I find more comfortable and better sounding than the more popular (and more expensive) Comply tips. You may also find a suitable pairing with one of the many tips FiiO includes with the FH7 – all of which are excellent quality, though none of which quite matched the quality and comfort of Spiral Dots.
Building on the design cues and clever bass porting first seen in the FH5, the FH7 combines a larger (13.6mm) beryllium coated dynamic driver with four custom Knowles balanced armatures, and an improved acoustic design to deliver a sound more refined and resolving than all of FiiO’s previous IEMs.
Rated at 16-ohm impedance with a sensitivity of 111 dB/mW, the FH7 is easy enough to drive, but mostly immune to hum or hiss when used with a powerful amp or DAP. Paired with the M11, I could hear no audible hiss even in high-gain and the volume maxed out. With an extremely powerful desktop amp you may start hearing faint hiss at high volume levels. Should that be the case, a simple tweak like the addition of an ifi IEMatch in the chain reduces noise floor back to inaudible levels.
Coming from a warmer, bassier IEM like the FH5, my first impression of the FH7’s sound profile was closer to neutral, bordering on bright. You wouldn’t think so, given the increased size and better materials of the FH7’s dynamic driver, but FiiO has obviously opted for a more ‘reference’ sound, sacrificing some of the FH5’s heft and dynamics for extra speed and control. The addition of a ‘super tweeter’ ultra-high frequency BA driver has also added more resolution to the mix, notably improving the clarity and detail retrieval of predecessors. This does come at the possible cost of some high-frequency stridency, as we’ll discover later.
Interestingly, FiiO’s new filter system lets you dial in (or out) the amount of high-frequency information by blocking (red filter), partially blocking (black filter) or leaving open (green filter) the sound path from the super-tweeter, which is placed front and centre of the nozzle opening. In other words, the filters don’t directly affect the low or mid frequencies at all; rather, they attenuate the highs and in so doing give the other frequencies more or less emphasis in the mix.
The filter system mostly works well, although the changes it makes are subtle compared to a more involved filter system that found in IMR’s Zenith (reviewed here) or new Aten IEMs. This can be a good or bad thing, depending on your sound preferences. The filters alone won’t suddenly turn the neutral-tuned FH7 into a warm and dark IEM, even with the red (bass) filter in place; nor will it do much to the placement of the mids. Many users actually prefer the fully open green filter, which maximises the FH7’s excellent treble extension and air. The filters are thus useful in tweaking nuances of sound, but less so in terms of changing the overall character of the IEM.
To get a better understanding of how the FH7’s sound in real-world conditions, I ran them through a long set of test tracks and albums over the course of the past month. All of these tests were done with the M11 using a balanced cable, Spiral Dot tips, and lossless FLAC files (both standard and high-res).
Turn to page 3 for sound impression specifics…