KZ D-Fi Earphones Review – The Fullmetal Alchemist

KZ D-Fi Earphones

Make Life Click is reader-supported. We may earn a commission for purchases using our links. More details

Current testing methodology is v1.2

Release Date
April 19, 2023
2.29 oz
0.79 x 0.39 x 0.39 in

The KZ D-Fi is an affordable pair of earphones from the Chi-Fi brand KZ. It comes in a standard version and a tunable version with the ability to affect tuning nuances in songs.

I’ve tried many earphones from the brand but this is the first time I’m trying out a KZ earphone that has tuning switches. Let’s see how it does!

Editor’s Pick


Affordable KZ earphones with tuning switches.

Price Range: $
Brand: KZ
KZ D-Fi inside the box


The KZ D-Fi is a single dynamic driver in-ear monitor with a warm neutral sound signature. The sound is organic and natural paired with good upper-end extension and technicalities. The frequencies can attain some good note weight using one of the bass switches or a combination.

Meanwhile, the gain switch can boost a noticeable presence across the board. Although there are purportedly 16 different tunings, most combinations are negligible when graphed. The tuning switches do work, but you don’t get that much distinction from the base tuning aside from adding in body or presence.

Still, I have to commend KZ for creating a model that’s unique among all of KZ’s earphones. Considering sonics and its all-metal build, the D-Fi satisfies both criteria for good sound and good value even through the eyes of dyed-in-the-wool audiophiles.

The Specs

  • Driver:  10mm Dual Magnet Dynamic Driver
  • Frequency response:  7Hz-45,000kHz
  • Impedance:  29Ω – 48Ω
  • Sensitivity:  110dB/mw

What’s in the Box?

  • KZ D-Fi earphones
  • 3 x pairs of silicone ear tips
  • 1 x pair of memory foam tips
  • 3.5mm jack silver-plated cable
  • 1 x tuning paddle
  • 1 x user manual

Stuff I like

  • Multiple tuning nuances with the use of switches
  • Warm neutral signature
  • Expressive midrange and quality bass
  • Natural timbre and tonality
  • Sparkly treble

Stuff I like less

  • The shells can be too heavy for some ears

Comparable products to consider

Raptgo Bridge
Raptgo Bridge

As a more premium option, the Raptgo Bridge offers tuning filters and switches so you can shape the sound according to your preferences.

First Impressions

The KZ D-Fi comes in standard KZ packaging which is unremarkable. This is something to be expected considering how affordable they are.

Out of the box, these earphones look stunning.

The KZ D-Fi can’t be justified by any of the photos online – one must hold it in their hands to truly marvel at its beauty and the level of workmanship it has undergone. 

Although this may sound intense and exaggerated, there’s that wow factor and awe the first time I picked up the D-Fi in my hands.

The accessories, on the other hand, are pretty basic. Apart from the tuning paddle that you can only get with the tunable version, you get the detachable cable, extra ear tips, and a pair of memory foam tips.

KZ D-Fi - Design
Metal shell with a mirror-like, polished alloy faceplate | Make Life Click

Build Quality

The KZ D-Fi has a premium look and feel. 

It has an all-metal build that has quite the heft and you can almost be fooled into thinking it’s a mid-priced set. The design is odd but in a very interesting and alluring way. 

I couldn’t put my finger on it but after some time, it started to look like a personified Alphonse from Fullmetal Alchemist – which is off the charts in trying to describe how cool it is. 

Overall, it looks well-built and could withstand heavy usage.

Fit and Comfort

Regarding fit and comfort, the D-Fi has a nice and snug fit in my ears using one of the small ear tips I stole from my Raptgo Bridge

Some users may feel that it’s a little bit heavy on the ears but this may depend on the ear shape and size. I can’t attest to this being the case generally.

 Overall, in my experience, ergonomics and comfort are spot on and I don’t have any issues. 

Tuning Switches

The tuning switches are almost a no-brainer concept. It’s nothing new but for a set in the KZ D-Fi’s price range to have the feature is quite novel. 

KZ claimed that it has 16 different tunings but to be honest, the changes are more of nuances rather than distinct ones. 

A simple guide to follow would be that the three bass switches raise 1db of gain on the lower region and the fourth switch (which is a gain switch) raises the signal across the board by a few notches. 

The bass switches affect the degree of rumble and bass impact while also providing note weight. Meanwhile, the gain switch raises the whole signal’s presence. Happy exploring.

KZ D-Fi - Tuning Switch
Equipped with precise 4-gear electronic switches | Make Life Click

Sound Quality

In this review, I’ll be going through sound a little differently than I normally would. 

We’ll be taking a look at the lower and upper midrange frequencies gauging the sonics of male vocals and female vocals using the different tuning configurations the D-Fi has. 

Testing was done at 50% volume using my Shanling UA1 ported through my laptop. 

In the first song, “Heart to Heart” by Mac De Marco, we’ll be taking a look at the effects of the switches on lower midrange playback with male vocals.

  • On the default setting (DDDD), Mac’s voice sounded full-bodied with a good amount of texture The instruments mixed harmoniously with the vocals. Everything in the standard configuration sounded pretty balanced and natural. Male vocals had good definition and weight while remaining transparent and clear-sounding.
  • Turning on the first bass switch (UDDD) added in a sprinkle of sub-bass and a little bit of note weight. The sub-bass wasn’t overpowering, lending just an extra bit of oomph. It enhanced the lower end’s presence and threw in some added impact. For those who desire a bit more sub-bass, flicking on the first switch would be optimal.
  • On the (UUDD) setting, I found myself intoxicated with the bass. It had a rich and deep tone. I was still able to appreciate Mac’s voice, which remained clear and unmuddied. But I think the bass presentation was very distracting with regard to trying to listen to the song as a whole.
  • With 3dB of bass gain on the (UUUD) setting, the rumble was intense and enveloping. It added some beefy weight to Mac’s voice. It was oddly enjoyable as it was disorienting. Mac’s voice maintained good audibility and had more weight. 
  • Trying out the (DDDU) setting sort of cleaned Mac’s voice of its syrupy nature and improved the overall vocal expression and delivery. Microdetails were noticeably better as the bass took a backseat while participating to make for a more balanced sound. Mac’s voice did lose most of its weight and sounded a little bit lacking in heft. 
Ergonomic cavity design ensures comfortability when used | Make Life Click

Overall, I found playing with the bass switches adds a good amount of presence to lower frequencies, fleshing out more texture and presence but comes at the expense of the fainter microdetails.

A combination of one bass switch and the gain switch seems to be the best configuration, providing a very balanced yet engaging listening experience with good note weight and naturalness.

The second song for testing is “The One That Got Away” by Katy Perry. 

  • Listening to Katy Perry’s voice on standard tuning (DDDD), the nuance and texture were heard. I find turning up just one bass switch added grunge and body to her vocals. This setting enhanced the low end with more presence while making the mid-bass more impactful.
  • Using the (UUDD) setting sacrificed upper midrange clarity for increased low-end presence and mid-bass impact. The shimmer and transparency were noticeably lessened with the two bass switches active.
  • With (UUUD), the bass became domineering and distracted from the main vocal line. It added a body to Katy’s vocals, but I appreciated it more when it was lighter and more transparent sounding. 
  • When all switches were on (UUUU), the bass was thunderous and the vocals gained beefy weight. However, the overall frequency became thick, which may be a preference-based pro or con.
  • Trying out the (DDDU) was interesting as the bass texture and presence were sublime and hit the sweet spot while the rest of the frequencies retained their transparent nature with better microdetails. 

I realized that depending on the song, I may or may not opt to flick up a bass switch. On the second song, I saw no need as the bass was already pretty big in the mix, to begin with. 

KZ D-Fi cable
High-purity silver-plated wire for better transmission of sound | Make Life Click


The bass of the KZ D-Fi has good texture and presence. It can vary the tuning with the use of the bass switches. 

For the most part, it’s a good-quality bass with good speed and impact.


The midrange is very neutral and organic. It handles vocals with great adeptness, portraying texture and nuance with grace.


The treble has a good extension with ample air in its upper frequencies. The high-end sounds sweet and brilliant without introducing any sibilance or harshness.


The KZ D-Fi is backed up with good technicalities. The attack and decay are the most natural I’ve heard in its price range. 

The stage remains intimate but paired with good sustain as it’s life-like and organic. 

The D-Fi is generally well-resolving and I’ve found that it handles microdetails as well as it does for macro details. 

The instrument separation is decent, with each instrument just beside each other’s thresholds and the layering remains tidy while melding perfectly together.

KZ D-Fi - What's in the box
What’s in the box | Make Life Click


The KZ D-Fi is fun as it is natural. It’s neutral with great musicality and although it’s the most neutral KZ I have heard, it doesn’t come across as sterile or boring. And the bass switches are absolutely fun. 

KZ D-Fi in-Ear HiFi Earphones Metal High Resolution Wired Earbud Headphone with 4-Level Tuning Switches HiFi Stereo Music Sport Monitor Earbuds with 2pin Detachable Cable(Black,with Tuning Switch)

You get more presence and slam but in consideration of balance, which is skewed quite easily with turning on more than one bass switch, I find flicking on only one of the bass switches yields good presence and texturization while preserving the frequency’s overall balance. 

The gain switch is easily a winner for me and if you want the loudest configuration that yields more presence across the board, you can opt to flick it up. 

With the build quality, aesthetics, and sonics, the KZ D-Fi’s standard and tunable version gets a definite recommendation from me. For the price, it’s definitely some mad alchemy that KZ was able to accomplish.

KZ D-Fi inside the box
Sound Quality
Build Quality
Comfort and fit
Value for money

Gavin is a college student who has a lot going on. From collecting IEMs and modding mechanical keyboards, to different hobbies like digital drawing, music mastering and cooking. It is safe to say he is a complete multi-faceted geek (and he's kinda cool too)

This post was last updated on 2024-05-18 / Some images from Amazon Product API & some links may be affiliate links which may earn us a commission from purchases.

Helpful? Sign up and get more interesting posts like this. No Spam.

Get access to insights, deals, competitions and giveaways. Unsubscribe anytime.

* indicates required

Leave a Comment

Your email address will not be published. Required fields are marked *

Amazon and the Amazon logo are trademarks of, Inc. or its affiliates.