FiiO
FiiO - K9 Pro ESS (Unboxed)
Flagship Desktop DAC & Amplifier
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2 days
Chi-Fi
Excellence
Ideal for
Indoor Use
Bluetooth with LDAC,
aptX HD & atpX Adaptive
4-Pin XLR & 4.4mm
Balanced Output
ESS Sabre ES9038PRO
Dual DAC Chip
Connect With
Optical, Coaxial & RCA
≥2.1W @ 32Ω
Power Output
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Returned headphones are fully functional products that have left the warehouse and therefore can no longer be sold as new as their packaging has been opened. The product may have been used once or twice by the customer who returned it.
Transit Damages
Sometimes we receive headphones in damaged packaging due to shipping accidents. These are brand new headphones with cosmetic flaws on the packaging.
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Since you won't get the original packaging, we give you a good discount compared to a new headphone.
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A thorough inspection means you receive a 100% working headphone with no sound output issues.
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All unboxed headphones carry the same warranty period as a brand new headphone would.
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ALL Original Accessories
The unboxed headphones itself comes with all original accessories.FIIO PRESENTS THE UPGRADED K9 PRO EQUIPPED WITH A DUAL ESS SABRE CHIP FOR PRISTINE AUDIO
FiiO introduces the flagship desktop DAC and Amplifier that houses the best components and features the latest engineering innovations. The team at FiiO has equipped the K9 Pro ESS with two high-performance ES9038PRO DAC chips made by ESS Sabre. The ES9038 Pro is a flagship-grade 8-channel DAC chip that is capable of providing ground-breaking performance in decoding high-resolution audio signals and offers 7 digital filters. FiiO has upgraded the K9 Pro ESS from the K9 Pro in terms of DAC count, the K9 Pro had only a single AK4499 DAC, and the latest K9 Pro has dual ES9038 Pro DAC Chips. With the help of this new DAC chipset, the K9 Pro ESS achieves ultra-low THD+N(<0.00025%) and high SNR(>129dB) ratings ensuring a super-clean performance.
EXEMPLARY DUAL THX AAA AMPLIFIER CIRCUIT DELIVERING AMPLE POWER TO DRIVE ANY HEADPHONE
FiiO K9 Pro ESS not only acts as a high performing DAC but also offers Amplification functions. Equipped with a pair of THX AAA 788+ chips, the K9 Pro ESS provides vivid details and dynamics whether you are using low or high-impedance headphones. The K9 Pro ESS with the THX AAA 788+ chip can output up to 46Vpp transients while driving high-impedance loads and up to an undistorted 2W when pushing low-impedance loads. The embedded THX AAA chip can produce an undistorted 1100mW under a 300ohm load and an undistorted 2100mW under a 32ohm load, 50% higher than the original THXAAA 788 amplifier chips with higher heat dissipation efficiency.
FULLY DIFFERENTIAL AND BALANCED DESIGN WITH A DUAL FEMTOSECOND CLOCK AND SIX-STAGE CIRCUITRY
The K9 Pro ESS is engineered to offer the best audio performance. To achieve this, a fully differential and truly balanced design is utilised for the K9 Pro ESS. Such a design ensures minimal interference between different components to fully maintain all details and the large dynamic swings in music for unmatched sound quality. Differential signals go through the four channels of the DAC, four channels of volume adjustment, and four channels of Amp for a truly balanced design. It also has a six-stage audio circuitry to ensure the users get the best possible sound performance. The analogue and digital circuits have separated paths with partitions for clean performance. Using an ultra-precise clock management system, the K9 Pro ESS can maintain maximum quality no matter the source. Dual asynchronous femtosecond clocks decode USB and Bluetooth sources, while automatic PLL clocks decode optical and coaxial sources.
FAST AND RELIABLE HI-RES BLUETOOTH CONNECTIVITY WITH LOSSLESS MQA DECODING CAPABILITY
Like every aspect of the FiiO K9 Pro ESS, it features the latest in Bluetooth technology to offer Hi-Res quality audio wirelessly. The FiiO K9 Pro ESS employs the Qualcomm QCC 5124 to handle Bluetooth connectivity, with support for formats such as AAC, SBC, LDAC, aptX, aptX LL, aptX HD and aptX Adaptive. This chip ensures that Bluetooth connections are both reliable and quick, satisfying both the low latency needs for games/videos and the high bitrate necessary for high-resolution audio. With the latest technologies found in the K9 Pro ESS, it supports the unfolding of MQA tracks, allowing you to listen to high-resolution audio files that are not only compact but also retain the master-level sound quality that brings you directly into the recording studio. Apart from these high-res MQA Support, the K9 Pro also supports high-res 32-Bit/384kHZ PCM as well as native DSD256 decoding.
ADVANCED POWER DELIVERY WITH LDO’S AND PORTIONED CHASSIS DESIGN FOR LINEAR TRANSMISSION
The FiiO K9 Pro ESS features a highly regarded linear power supply. The K9 Pro ESS’s linear power supply, with its low-frequency transformer and 4 massive 4700uF capacitors makes sure that the rest of the system gets abundant clean power for the whole system. The chassis of the K9 Pro ESS uses a portioned layout, wherein not only the power supply and signals are separated, but the analogue signal loop is also put in an independent section, guaranteeing the integrity of the audio signal being processed. The digital portions of the K9 Pro receive power separately from the analogue parts for effective shielding against audio interference between the two circuits. In each stage of the audio circuit, ultra-low-noise LDO is employed for voltage regulation. No expense was spared in ensuring a clean power supply, with the K9 Pro ESS in total having a substantial amount of 20 LDOs.
THREE WAY GAIN SETTINGS WITH ACCURATE VOLUME ADJUSTMENTS BASED ON ADC CURVE RECONSTRUCTION
OFFERING MULTIPLE CONNECTIVITY PORTS HOUSED IN A ELEGANT AND DURABLE ALUMINIUM CHASSIS
The simple, yet elegant all-aluminium black exterior of the FiiO K9 Pro ESS is anodised and finely sandblasted with painstaking craftsmanship for a textured, luxurious feel. Controls are clearly and intuitively laid out to make operating the device as smooth as possible. Rest assured, the FiiO K9 Pro ESS is the very definition of a reliable and loyal music partner in your collection. The FiiO K9 Pro ESS also comes with multiple connectivity options for easy connectivity. The front side features - XLR-4Pin, 4.4mm Balanced, 6.35mm Single Ended headphone outputs and the rear side features - 4.4mm Balanced Line In, Coaxial, optical, RCA, XLR out for more convenient connections to external amps and speakers. There is also a USB Type-C port on the side for easy connectivity.
ELEGANT USER INTERFACE WITH DEDICATED APP AND METAL SWITCHES TO CONTROL VARIOUS FEATURES
The FiiO K9 Pro ESS comes with a dedicated app to control various features of the device. Built-In Bluetooth Low Energy (BLE) technology allows you to use the FiiO Control App to control functions like channel balance and sleep timer, even when not in Bluetooth mode. This feature is handy and offers convenience. Controls are clearly and intuitively laid out for an effortless experience. Metal switches are used for controlling input selection and gain level to help you easily and quickly switch to your desired method of listening. The stainless-steel volume knob blends seamlessly with the alluvium alloy front panel to give a luxurious experience while controlling your music. The RGB indicator lights surrounding the volume knob can light up differently depending on the current playing sampling rate. The FiiO K9 Pro also comes bundled with a custom stand that reduces the amount of space the K9 ESS Pro takes on your desktop, it also allows for more efficient dissipation of heat through convection – making the stand a true example of both form and function.
| MODEL | K9 Pro |
| COLOR | Black |
| WEIGHT | ≈2750g |
| GAIN | L/M/H |
| BLUETOOTH FORMAT INDICATION | Supported |
| FIRMWARE UPGRADE | System firmware and Bluetooth version can be upgraded via USB |
| LOW BATTERY REMINDER | NA |
| BLUETOOTH TRANSMISSION | NA |
| BLUETOOTH FORMAT INDICATOR | SBC: blue, AAC: cyan, aptX HD: yellow, aptX: purple, aptX LL: purple, LDAC: white, atpX Adaptive: green |
| MAXIMUM SUPPORTED SAMPLING RATE | 384kHz-32bit/DSD256（USB DAC） 192kHz-24bit (coaxial) 96KHz-24bit (optical) |
| HARDWARE SOLUTION | DAC: ES9038PRO*2, USB: XMOS XUF208, Bluetooth: QCC5124, LPF: OPA1612 * 2, volume IC: NJU72315 * 2, AMP: THX AAA788+ * 2, linear transformer |
| VOLUME SCROLL | Potentiometer+ADC Sampling |
| CHANNEL BALANCE | L12~R12 (0.5dB per level) |
| FIIO CONTROL | Supported |
| SAMPLING RATE INDICATION | Supported |
| DEEP STANDBY | Long press the multi-function button for about 3s |
| BLUETOOTH RECEIVER (5.0) | AAC/SBC/aptX/aptX LL/aptX HD/LDAC/atpX Adaptive |
| DIMENSIONS | ≈200x224.5x72mm (excluding feet) |
| CHARGING INDICATOR | NA |
| RECOMMENDED HEADPHONE IMPEDANCE | 16~600 Ω |
| BUTTON | Physical key + toggle switch |
| SINGLE-ENDED LINE INPUT INTERFACE | RCA socket |
| SPDIF IN | Optical fiber socket |
| BALANCED OUTPUT INTERFACE | 4.4mm socket, XLR4 balanced socket |
| BALANCED LINE OUTPUT INTERFACE | XLR3 balanced socket |
| USB | Type-C, USB B (data transmission) |
| BALANCED LINE INPUT INTERFACE | 4.4mm balanced socket |
| DIGITAL COAXIAL INPUT INTERFACE | RCA socket |
| HEADPHONE OUTPUT INTERFACE | Standard 6.35 mm socket |
| SINGLE-ENDED LINE OUTPUT INTERFACE | RCA socket |
| POWER SUPPLY | AC 110-115V~/AC 220-230V~ （Recommended） |
| CHARGING TIME | NA |
| BATTERY CAPACITY | NA |
| PO BATTERY LIFE | NA |
| THD+N | ＜0.00042%(1kHz/10kΩ/dbA) |
| CROSSTALK | ≥115dB (1kHz/10kΩ) |
| FREQUENCY RESPONSE | 20Hz~20kHz (-3dB) |
| SNR | ≥123dB (dbA) |
| NOISE LEVEL | ＜1.9μV（dbA） |
| LINE LEVEL | 2.5Vrms (1kHz/10kΩ) |
| THD+N | ＜0.00025%(1kHz/10kΩ/dbA) |
| CROSSTALK | ≥125dB (1kHz/10kΩ) |
| FREQUENCY RESPONSE | 20Hz~50kHz (-1.5dB) |
| SNR | ≥128dB (dbA) |
| NOISE LEVEL | ＜1.9μV（dbA） |
| LINE LEVEL | 5Vrms (1kHz/10kΩ) |
| CONTINUOUS UNDISTORTED OUTPUT POWER 1 | ≥1.1W（16Ω / THD+N＜1%， AUX IN) |
| CONTINUOUS UNDISTORTED OUTPUT POWER 2 | ≥2.1W(32Ω/THD+N＜1%，AUX IN) |
| CONTINUOUS UNDISTORTED OUTPUT POWER 3 | ≥281mW（300Ω / THD+N＜1%，AUX IN) |
| NOISE FLOOR | ＜2μV（dbA，AUX IN) ＜3μV（dbA，UAC/SPDIF/BT IN） |
| FREQUENCY RESPONSE | 20 Hz~50kHz (-1.5dB) |
| OUTPUT IMPEDANCE | ＜1Ω（32Ω） |
| CROSSTALK | ≥75dB (1 kHz/32Ω，AUX IN) |
| THD+N | ＜0.00033% (1 kHz/32Ω/dbA) |
| SNR | ≥129dB (dbA) |
| MAX OUTPUT VOLTAGE | ＞26Vp-p |
| CONTINUOUS UNDISTORTED OUTPUT POWER 1 | ≥1.1W（16Ω / THD+N＜1%) |
| CONTINUOUS UNDISTORTED OUTPUT POWER 2 | ≥2.1W（32Ω /THD+N＜1%) |
| CONTINUOUS UNDISTORTED OUTPUT POWER 3 | ≥1.1W（300Ω / THD+N＜1%) |
| NOISE FLOOR | ＜3μV（dbA， AUX IN） 4.5uV(dbA,UAC/SPDIF/BT) |
| FREQUENCY RESPONSE | 20Hz~50kHz (-3dB) |
| OUTPUT IMPEDANCE | ＜1Ω（32Ω） |
| CROSSTALK | ≥114dB (1 kHz，AUX IN) |
| THD+N | ＜0.0003% (1 kHz/32Ω/dbA) |
| SNR | ≥123dB (dbA) |
| MAX OUTPUT VOLTAGE | ＞52Vp-p |
| WHAT YOU WILL GET | 1. FiiO K9 Pro ESS |
| 2. Power Cord | |
| 3. Square port USB data cable | |
| 4. Bluetooth antenna | |
| 5. 6.35mm male to 3.5mm female Headphone jack adapter | |
| 6. Quick start | |
| 7. Warranty card | |
| 8. Instruction card for voltage selection | |
| 9. Fuse | |
| 10. Voltage protection plug | |
| WHAT YOU WILL NOT GET | 1. Original packaging of FiiO K9 Pro ESS |
2. Slight difference on the internal circuit: due to needs on adjusting the power supply, indicators and sound properties, we have made some slight adjustments on part of the electric circuits (But the key parts are still the same, as excellent as the former ones).
3. Slight improvements on the output power, distortion and SNR compared to the FiiO K9 Pro.
【Main differences in the structural portion】
1. Due to larger output power, we have designed heat dissipation holes on both sides to help dissipate more heat. (Placing the FiiO K9 Pro ESS horizontally can help to dissipate more heat).
2. The volume knob was changed to a PVD processed gold one, which looks more attractive.
3. The internal structure has been improved to dissipate more heat.
4. Included are the support stand and isolation feet, helping to save more space on the desktop when placed vertically.
[Android phone]
1. FiiO K9 Pro ESS input setting: FiiO K9 Pro ESS [INPUT] switch to USB gear
2. FiiO K9 Pro ESS output setting: switch to the corresponding output port according to the interface used, switch to [HP] on the front panel, switch to [PRE] or [DAC] on the rear panel
3. Connect the phone and FiiO K9 Pro ESS via USB data cable (both side and back data ports are available)
[IPhone/iPad]
You need to purchase a Lightning to TypeC data cable which supports OTG function(e.g. FiiO LT-LT1) to connect FiiO K9 Pro ESS and iPhone/iPad/iPod, and you can enjoy high-quality music by playing songs.
2. Open the Bluetooth settings on the phone, and click after finding FiiO K9 Pro ESS
3. Select the corresponding headphone port output
[Clear Pairing]
If you have connected to other Bluetooth devices, you can long press [INPUT] for 5 seconds to force the FiiO K9 Pro ESS to pair with the new device.
After turning on the K9 Pro, the Bluetooth control function of FiiO K9 Pro ESS can be used at any time, as long as it is turned on, you can set the K9 Pro through the software without switching to BT mode.
Why is there no response when Bluetooth is connected?
1. Clear the pairing of FiiO K9 Pro ESS
2. Delete the FiiO K9 Pro ESS from the Bluetooth settings on the phone and then pair it again
3. Long press [INPUT] to clear the pairing, and the FiiO K9 Pro ESS will re-enter the pairing mode with the red and blue lights flashing
2. Input settings, connect the coaxial or optical fiber cable to the corresponding input port
3. Output settings, switch to the corresponding output, connect headphones to realize the decoding function of FiiO K9 Pro ESS
[Note]
The FiiO player uses coaxial output. Please pay attention to use the coaxial adapter cable, change the PO output to SPDIF, and change SPDIF to D2P.
Coupled with the blessing of THX, the sound reproduction is relatively high, and the background sound is clean; the soundstage is regular (longitudinal and horizontal are regular)
In addition, due to the high magnification and strong driving ability, when matching different headphones, please pay attention to matching gain and volume.
Although they are all headphones, some have high sensitivity, you can use medium gain + large volume for them which will make the sound softer and more delicate. If the sensitivity is low, it is recommended to use high gain + loud volume to get sufficient power.
1. After decompressing the folder, install the Foobar 2000 and FiiO DAC driver
2. Use the data cable to connect the computer and the decoding device: K9 Pro, Q3, BTR5, etc.
3. Open the playback software Foobar2000 and set the output to: ASIO: FiiO ASIO Driver, some computers will not switch automatically, you need to switch the computer's audio output device to the corresponding decoding device
Additional settings are required to play DSD
1. Install the components, install all the plug-ins of the package
2. Click output, select the output mode ASIO: foo_dsd_asio
3. Click on SACD decoder, drive mode selection: DSD
4. This needs to be set according to different decoding devices. DoP Marker 0x05/0xFA is preferred. Some decoders also support ASIO Native"
Generally speaking, whether a set of equipment can successfully unfold MQA tracks can be analyzed from the direction of the audio signal.
Audio signal direction: audio source -> playback software, playback equipment -> connection cable -> FiiO K9 Pro ESS
1. Audio source: the song is MQA coded track
2. Playback software: supports MQA playback, if the software does not support it, only ordinary lossless tracks will be played.
3. Playback device: install software that supports MQA on your mobile phone or buy a player that supports MQA, such as FiiO M11 Plus LTD.
4. Adapter cable: When connecting the MQA decoder, the player and the decoder need to be connected with an OTG adapter cable. Both USBs of FiiO K9 Pro ESS can be connected to the mobile phone or the player through the OTG adapter cable to unfold MQA
5. FiiO K9 Pro ESS only supports USB MQA unfold, the panel output button [OUTPUT] pay attention to the corresponding output.
According to the feedback from most audiophiles after listening to both of them, AKM is more musical, while ESS is of higher quality. There is no better or worse between them.
Since everyone's listening experience is not exactly the same, it is recommended to try and compare them before buying to choose your favorite and appropriate one.
Just like the FiiO K9 Pro, we found during testing that noises would occur when playing DSD512 and above 768k sampling rate. We have attempted many times yet still cannot absolutely settle it. Since we have strict quality controls and there are not many DSD512 and 768k sampling rate songs on the market, we decided to leave DSD512 and 768k sampling rate behind.
2. Power cord*1
3. Square port USB data cable*1
4. Bluetooth antenna *1
5. 6.35mm male to 3.5mm female Headphone jack adapter*1
6. Quick start*1
7. Warranty card*1
8. Instruction card for voltage selection*1
9. Fuse*1
10. Voltage protection plug*1
[Why do you use the fuse?]
The fuse is used to cut off the power supply when there is a short circuit or voltage mismatch, which protects the FiiO K9 Pro
It can be replaced with other fuses of the same specification, fuse tube specification @T 250V500mA H 5.2x20mm
[Where should the red voltage level at the bottom be toggled? ]
The voltage protection plug is plugged to the bottom to prevent dust. There are two voltage ranges of 110V and 220V, which can be adjusted to the corresponding voltage according to the local voltage range.
1 Year Warranty
Don't sweat it, this FiiO - K9 Pro ESS (Unboxed) comes with a warranty
from FiiO that covers manufacturing defects.
All products featured on Headphone Zone are backed by an original manufacturer's warranty.
Read more about FiiO's warranty in India.
GOLD AWARD
SoundNews.net
Mar, 2022
"If the M17 was out of your budget then the FiiO K9 Pro ESS is the more affordable and wiser choice for headphone users. You get a very similar coloration and presentation style for one-third of the price."
Read More
"K9 PRO is a well-crafted, well-thought and great sounding unit, that will be putting to shame pricier units,. Good tonality/timbre versus all other THX-AAA equipped devices, Good layering and depth."
Read MoreThank you Headphone Zone team for timely delivery especially in this situation and bringing this product to India I recommend everyone to check this one before considering other alternatives in the market.
Good Purchase with Good Delivery Experience!!! Delivery Experience - Extremely satisfied. The packaging was sufficient and delivered 2 days before the committed delivery experience. Delivered in almost 48 hrs.
Good and quick delivery from Headphone Zone and would recommend others to buy from them too. No issues from their end whatsoever.
Amazing support from the Headphone Zone team, this is my second product purchase. Delivery at critical times (COVID19), is just awesome, received my headphones one day before the committed time. Kudos to the team.
It’s one of the best sites to get premium quality headphones. Their service is unparalleled!! Would recommend 10/10. A Grade service!!
Experience was smooth. The Headphone Guru was kind and answered all my queries. The delivery was super fast. The product is genuine This is my go-to destination for everything audio from now on.