I’ve been sitting on the FD5 for about a month now, and wanted to share my impressions.
For context, my main IEM of late has been the Sony IER-M9. Prior to that, my primary driver was the Sony XBA-Z5. Other single DD IEMs I’ve owned include the AK T8iE MKII (warmer, darker cousin of the Beyerdynamic Xelento) and the Sony EX1000.
Spotify Premium on Mac > iFi ZEN DAC Balanced > iFi ZEN CAN Balanced > FiiO FD5
I’ll state upfront that I was frankly disappointed when I heard the FD5 out of the box. I really liked the bass (meaty, plenty of slam) and the mids (full, euphonic), but I found its technicalities fairly lacking.
I ran through a bunch of tips—stock Balanced, stock Vocal, Symbio W, Symbio Peel, Acoustune AET07, Azla Sedna—but simply wasn’t hearing the staging, holographic imaging, or resolving capabilities that they had been praised for in reviews.
More specifically, I thought the separation, imaging, and detail were below average for its price point. Muddled sounding, even. Upper-mids/lower treble also tended to display a certain harshness, upper-treble was poorly articulated, diffuse, and splashy, and there was a distinct lack of refinement to the sound as a whole.
On a whim, I tried the SpinFit CP145 tips, and that made a world of a difference. There was the staging and technical capability that I’d read about. Gone was the upper-mid harshness and dissonance between the lower and upper mids. Upper-treble became well-extended, well-articulated, and refined.
My sonic priorities are pretty well-defined at this stage in the game: bass, soundstage, timbre, dynamism, liveliness. The FD5 checks all these boxes, with fantastic technicalities to boot.
At its price point, the FD5 are exceptional by virtue of their staging and presentation alone. There isn’t the closed-in quality or small images that characterises most IEMs, or the “ants playing in a concert hall” type effect that appears even with IEMs with large stages. This is a big and bold presentation.
Then, there’s its analog tonality. I’ve really only heard two other IEMs that exhibit a similar tone: the Sony EX1000 and the Periodic Be. Both these IEMs, along with the FD5, evoke an unvarnished—though by no means unrefined—vinyl-esque quality. The BLON BL-03 sort of shares this quality too, but not quite as closely. The AK T8iE MKII, despite being a single DD unit, is farther behind still in this regard.
The closest approximation to the tonality and presentation of the FD5 in my estimation would be the Sony EX1000, albeit with a smoother treble and a healthy added dose of bass slam, weight, and grunt. A lovechild of the Sony EX1000 and the Sony XBA-N3, if you would. I do want to caveat here that it's been a while since I've had EX1000, so I won't comment on their relative performance in terms of technicalities.
Of the V-shaped IEMs I’ve owned—AK T8iE MKII, Fearless S8F, Sony XBA-N3—I’d pick the FD5 everyday.
If it isn’t clear at this point, I dig the FD5, and I dig ‘em hard.