The FiiO FH5S is another hybrid IEM that sports a semi open back design made of two dynamic drivers and two balanced armature drivers. One of the appealing features of the FH5S is its multi dipping sounds of which it can be modified to fit perfectly to one’s liking as three tuning switches for bass, mids and treble are provided. In this very detailed review, we will limit our attention to the frequency response of the FiiO FH5S only, looking at the interaction of the driver technologies, the differences made by the tuning switches, and also the performance of the IEM across the frequency spectrum.
Overview of Frequency Response
Frequency response is the measure of the ability of sound equipment to reproduce sound of different frequencies, from lowest possible bass to the highest treble. In simple terms, a flat frequency response can be defined as the reproduction of all frequencies without any missing or fitting in of any part of the frequency range. Nevertheless, there are headphones and IEMs that also sound better since they have their own signature tuning that boosts some frequencies while cutting off others. This is what gives IEMs like the FiiO FH5S their sound characteristic.
The FiiO FH5S, in general, is characterised by and comes with a factory default setting that has what is referred to as a `W shaped’ frequency response meaning the low, mid and high frequencies are all slightly enhanced than the neutral reference tuning of the levels. This is very lively and lets the listener appreciate a lot of different features of the music especially combined with the tuning switches which allow for the most subtle adjustment of the balance of sound.
Low Frequencies (Bass)
In terms of frequency response, the bass spectrum lies from about 20 Hz to 250 Hz, which includes the sub-bass (20-60 Hz) and mid-bass (60-250 Hz) regions. In the case of FiiO FH5S, the low frequencies are managed by a 12mm dynamic driver and per Beryllium coating optimized for fast bass reproduction with a nice punch and excellent control.
Sub-Bass (20-60 Hz)
Sub-bass can go as low as you desire and very powerful on the FiiO FH5S in activation of the bass tuning switch on the device. This switch raises the sub-bass shelf, thus boosting the output in the lower end of the spectrum. Sub-bass frequencies are articulated convincingly in the FH5S and therefore this product is excellent for anyone who loves modern electronic, hip-hop, or pop music where bass is normalized. Bass presentation still fares well with the FH5S without the bass switch but the sub bass is more refined and less extreme than other bass tuned IEMs.
When the bass switch is switched off, the sub-bass exists but it is less pronounced, creating a more neutral sound. This is especially desirable for Avenue such as classical, jazz, or even acoustic music, as these genres tend to focus more on harmony, and excessive sub-bass may disrupt the mix.
Mid-Bass (60-250 Hz)
Between the bass and the midrange is where the FH5S provides an excellent punch. It gives the right amount of “thump” that makes the sound pleasing, and one can enjoy the engagement of drums, bass guitars, and electronic kick drums. With the bass switch on, mid-bass also goes up in the mix which often enhances the overall tone with warmth and richness. The FH5S also proves beneficial in that it is fun to use for the pleasant overuse of mid-bass energy in rock, pop and EDM, where mid-bass energy is important for maintaining rhythm and giving the music a punch.
Speed and control are two of the best qualities of the bass response performance of the FH5S. Despite its giving quite a punch, still the beryllium plated dynamic driver would manage to keep the control on the bass and prevent any over blooming or sagging that would otherwise bled into the midranges. Thus, the mid-bass will not dominate the other frequency ranges ensuring order and spacing of sounds produced by different instruments.
Bass Tuning Switch
The bass tuning switch is one of the key features that enhance the FH5S. Once the switch is on, it raises the average bass levels which involve the sub and mid bass as well. This is especially advantageous to listeners that prefer a lot of low tones in their sound signature but can also be turned off for ones who like the sound to be more balanced or neutral.
The tuning switch is not such an extreme device and does not enhance bass overall response severely; it however enhances about 3-4 dB which can be sufficient to alter the how the low end blends in with the mix as a whole. It is a small yet very functional adjustment to the bass response that fits various styles of music or personal choice.
Middle Frequencies
The midrange handles sound frequencies that are between 250Hz and 4,000Hz. This range also accommodates most of the vocal and instrumental pronunciations. The FH5S for the mids utilizes a balanced Knowles armature driver in the mids which is reasonably renowned for producing clear and detailed sounds. The midrange is also a very significant frequency range since it affects the reproduction of vocals and other sounds that are higher than say a guitar, piano, or any other instrument located in this range.
Lower Mids (250-1,000 Hz)
The lower midrange in the FH5S is rich and full in body especially with the midrange tuning switch in the default position. There is a realism in guitar and piano timbres, and even the dominant vocals do not sound far away. There is a level of warmth that ensures that the sounds of men and deeper sounding instruments are full-bodied, however the lower mids are not overly thick which helps in averting any chances of the mix being bleated or muddied.
When the midrange tuning switch is turned on, there is slight enhancement of the lower mid which pushes it slightly forward adding a bit more richness and presence to this region. This can help ‘bring forward’ the vocals and instruments in the mix especially in the genres that require clear and distinct separation of the mid frequencies such as classical, jazz or acoustic music even.
Upper Mids (1,000-4,000 Hz)
The upper midrange is the FH5S’s strongest suit. The Knowles balanced armature driver offers stunning detail and resolution in this frequency range, which makes the reproduction of voicing, strings, and other high-frequency insturments decent without sounding too harsh. Female vocals especially are done with such crystal clarity and brightness rendering, the FH5S is still able to control harshness and sibilance in the upper mids even with the midrange switch on.
The upper mids are intentionally pitched up in the default tuning of the FH5S which when integrated into the overall sound signature creates a feeling of liveliness and urgency of the presented sounds. This makes the IEM very dynamic and appealing especially with music genres which have high vocal clarity and a lot of midrange such as pop and rock and other vocal based music.
Midrange Tuning Switch
The midrange tuning switch provides a light boost in the lower and upper mid regions resulting in a more up-close and personal sound. Such a feature can be advantageous in rendering vocalists and even instruments over the mix especially in classical or jazz genre where the midrange is manipulated heavily to create a lifelike sound within a room.
Without the midrange switch, the FH5S produces a smooth and neutral midrange that is slightly less energised, thus making space for the bass and treble elements to be more pronounced. This results in a sound profile that is more suitable for laid back or casual listeners who prefer less aggressive and more natural bias of the sound.
High Frequencies (Treble)
Treble region is typically between around 4000 Hz to 20000 Hz and includes the sounds produced by instruments such as cymbals and hi-hats as well as some voicing harmonics. For the treble, the FH5S boasts in their arsenal a specially designed Knowles balanced armature driver meant to project sound in high frequencies with no distortion or excessive fatigue on the ears.
Lower Treble (4,000-8,000 Hz)
In the FH5S, the lower treble region is extended and airy, full of detal that adds sparkle. The sound of cymbals, hi-hat and other high-pitched percussion is sharp yet controlled but not piercing or sibilant. Treble response complements well the other frequencies giving a typical constricted midrange sound but with a feeling of air within the ears thus the FH5S sounds wide and open.
When the treble switch is on, the lower treble is increased, thus making the high frequencies more present and brilliant. It also means that the FH5S will be more complex and exposing in the better sense of the feeling that there is more sound energy in the form of treble even in the stringent music genres like for example electronic dance music or rock and metal.
Ultra Treble (8000 Hz-20000 Hz)
While the upper treble on the FH5S reaches well into the higher frequencies, this allows for more air and space felt in the sound. Furthermore, the semi-open head of the IEM helps with this too which aids in providing an airy and expansive soundstage as opposed to fully closed designs. This upper frequency region of treble is responsible for adding a twinkling and glowing effect on the music, which helps to create impression of high resolution and detail.
A plus in the treble response of the FH5S is that its treble can reproduce high-frequency details without being harsh or tiring on the ears. Even with the treble switch turned on, the treble is still smooth with proper control, and does not encroach into the territory of bright or sibilant treble, thus over more prolonged listening periods, the treble does not tire the listener.
Treble Tuning Switch
There are three tuning options available, and the treble tuning switch is probably the most conspicuous of the three, it adds a slight but noticeable increase to the overall treble range. Upward when turned on, treble switch, allows the enhancement of treble reproduction and brightening of overall sound. This is advantageous with music that incorporates fairly pronounced treble, like in orchestral or electronic music genres, or with people who simply enjoy a pronounced high end to their sound signature.
In the event that the treble switch is turned off, despite the fact that the FH5S offers quite a significant amount of treble energy, the attention to this particular frequency is somewhat lowered, producing a more relaxing and comfortable sound. This can be preferable for those that dislike treble or for styles of music that do not call for such a response in the higher frequencies.
Soundstage and Imaging
With its semi-open back construction, the FiiO FH5 S produces sound that is astounding for an in-ear device. This makes it easier for sound to breathe freely, providing the audience with the three-dimensional orientation that is usually absent in closed back IEMs. At the same time, it is quite easy to picture the sound of each instrument in the stereo space, making it even easier to locate it. Such details can especially be observed in the genres with harmonically rich structures, such as classical or orchestral music, where each instrument is neatly placed and can be distinctly heard.
It is because of the width that the soundstage presents that it feels like wearing headphones over the ears in the case of the FH5S, where sounds protrude past the ear. That quality furthermore enhances the listening experience, making it full and not stuffy. It is a perfect feature when dealing with live, ambient and cinematic soundscapes, where the surround presentation of sounds is the focus of concern.
Imaging or the accuracy and precision in putting sounds in certain locations within the soundstage is yet another forte of FH5S. Instruments and vocals are clear bordered, while the elements of the mix are distinguished well. Such clarity makes the content more enjoyable because the individual violin or harmonized voice can be distinctly heard without its interference by other sounds.
Tuning Switches: Adjusting the Frequency Response
One of the most interesting aspects of the FiiO FH5S is its system of tuning switches, which enhances the frequency response of the device to the preference of the user. There are three switches – each designed for different sections of the frequency range: bass, mids and treble. These switches make a small but appreciable change to the sound signature, thus the FH5S is flexible and suitable for a number of music genres and listening habits.
Bass Switch
The purpose of the bass switch is to extend the focus well beyond the confines of the standard audio range within both the sub and mid-bass playback. This low-end extension is especially useful for the people who like their EDM, hip-hop, or rock music with heavy bass drops. The switch adds quite a punch while the bass frequencies are boosted by approximately 3-4 dB, enhancing the sound and energy.
When not switched on, the bass is more controlled and less pronounced which would work well for those who seek a more flat response or for styles such as classical or acoustic which do not have a prominent bass line. For those keen on experiencing bass in its extremes, a switch that allows interchange between these two bass profiles is a welcome feature.
Midrange Switch
However, the midrange switch pushes the mids forward a bit to make it easier for the vocals and midrange instruments to cut through the mix. This is very important in such genres as pop, R & B and classical where the sound has to be rich and there is a considerable amount of emphasis on the midrange due to the vocal sections. The switch does not change the mids very much, but it somewhat accentuates them enough for one to hear them without cutting through the other frequencies in the mix.
At the midrange switch’s off position, things sound clear and defined, however, instead of being a little warm, it tends to stay more neutral. This is suitable for those who love balanced sound sigs with no colorization of any of the frequency ranges. In both cases the mids are still natural and creamy, they offer incredible detail and separation at the same time.
Treble Switch
With the treble switch activated, a bit more sparkle and air is added to the high frequencies, contributing to a perception of more detail and brightness in the sound. This is great for such music types as electronic and classical or even jazz, in which brighter treble is very energetic and adds definition to the sound as the treble switch is activated. The treble is boosted by around 3-4 dB making cymbals and hi-hats as well as female singers sharp but not shrill for example.
Hence, when the treble enhancement feature is switched off, the treatment of treble frequencies does not seem overly aggressive and is more relaxed. This is an advantage to those who tend to show aversion to treble or dislike a treble heavy sound signature. The FH5S shows satisfactory details and resolutions within the high frequencies even in the absence of any treble boost.
Frequency Response Summary
Bass (20 Hz – 250 Hz): The FH5S reproduces bass range that is deep and punchy while remaining well controlled. The sub-bass is present and strong, whereas mid-bass serves its role in warming up the sound with addition of energy. The bass switch permits a delicate enhancement of the low-end presence which satisfies the bass enthusiasts without being too heavy for the mix.
Midrange (250 Hz – 4,000 Hz): The midrange response is clear and detailed, and pleasantly balanced. The bass midrange has warmth and body, and the mid to high midrange is clear and uncolored, especially for vocals and instruments in the middle frequency range. The midrange switch slightly enhances the vocals, which sound more pronounced with the switch in that position.
Treble (4,000 Hz – 20,000 Hz): The treble is clean and well textured but not piercing. The lower treble gives definition and brightness while the upper treble reaches much higher frequencies to give a sense of air. The treble switch tends to add a little more brightness which increases the presence of details.
Final Thoughts
The FiiO FH5S is a remarkable hybrid IEM featuring a well-rounded frequency response that can be adjusted depending on one’s tastes given the tuning switch system. The bass is punchy and deep, the mids are clean and natural, and highs are bright and detailed without fatigue. Such capacity to adjust the frequency response further allows using the FH5S IEM across different music genres without limitations.
The semi-open back design enhances the soundstage and imaging and sound provided by the FH5S suits listeners who loves sound spatiality and good instrument separation. Be it a broad-banded sound signature for a basshead or treble head or just moderate output sound that comes out balanced, then customization offered by the FiiO FH5S allows the user to listen to their preferred sound.
As for the frequency response offered by the FH5S, it is a proper mid-range expecting sound that Engages even in audiophiles harsh listening periods. The Hybrid Dynamic & Armature system drivers ensure that no matter what part of the frequency spectrum is being reproduced, it is being done with utmost care and precision which lends to the overall enjoyment of the listening experience.
If you require a high-end IEM that has a flexible sound mode ranging from the softest and widest sound as possiбle, fit for the FiiO FH5S. It’s built well, has a decent sound quality range, and there’s some interesting frequency response adjustment possibilities which makes it one of the best hybrid IEM class within price range.