FiiO K9 Pro vs K9: Which Amplifier Delivers Better Sound Quality?

Picking between two audio amplifiers that look alike can be tricky, especially when they come from the same trusted brand. Audiophiles have debated extensively about FiiO K9 Pro versus K9, as both devices deliver outstanding sound quality at different price points.

The K9 stands as FiiO’s flagship desktop DAC/amp. Its sibling, the K9 Pro, takes sound quality to the next level with premium components and better features. The big question remains – does the Pro version deserve its premium price tag? And will your ears notice the upgrade?

We tested the FiiO K9 and K9 Pro ESS really well in different listening situations to give you a full picture. Let’s explore these powerful amplifiers and break down their technical specs and real-life performance to help you decide.

Technical Specifications Comparison

The technical core of these amplifiers reveals key differences that affect your listening experience. Let’s explore what makes them unique.

DAC Chip Differences: ES9038PRO vs ES9068AS

The K9 Pro has dual ES9038PRO DAC chips, each dedicated to a single channel. This premium setup achieves a remarkable signal-to-noise ratio of 129 dB. The standard K9 uses two ES9068AS DACs that deliver an excellent SNR of 124 dB. This difference stands out because the ES9038PRO is ESS Technology’s premium converter designed specifically for high-end audio equipment.

Power Output and Performance Metrics

Raw power is abundant in both units. The K9 Pro outputs:

• 2100mW at 32Ω (balanced)
• 1100mW at 300Ω (balanced)

The K9 delivers slightly lower but impressive power:

• 2000mW at 32Ω (balanced)
• 780mW at 300Ω (balanced)

Connectivity Options and Features

Both models share detailed connection options with notable differences. The K9 Pro has MQA rendering capabilities and a side-mounted USB-C port that you won’t find in the standard K9. These features are common to both units:

The K9 Pro’s dual femtosecond clocks for USB and Bluetooth decoding provide more precise timing management. Both units support high-resolution audio. The K9 Pro handles up to 384kHz/32-bit/DSD256, while the K9 extends to 768kHz/32-bit/DSD512.

Sound Quality Analysis

Our extensive testing with headphones and music genres of all types is complete, and we’re excited to share a detailed sound quality analysis of both units. These amplifiers show their differences in subtle yet meaningful ways.

Bass Response and Low-End Performance

The K9 Pro ESS delivers remarkably controlled and textured bass that decays instantly when tracks just need it. Its low-end performance shows excellent depth without bleeding into other frequencies. The standard K9 is nowhere near lacking – it maintains impressive bass control but doesn’t quite reach the same sub-bass extension. Both units handle complex bass passages beautifully, though the Pro version shows better layering and definition in the lowest frequencies.

Midrange Clarity and Detail

Each unit’s distinct character shines through in the midrange presentation. The K9 Pro ESS showcases vocals with outstanding articulation and vivid detail. It knows how to render even the smallest nuances in background instruments, which creates a more three-dimensional soundstage. The standard K9’s clean and balanced midrange stands strong, though instrument separation isn’t quite as distinct.

Treble Extension and Resolution

Both units excel technically in higher frequencies, but there are notable differences:

K9 Pro ESS:

• Delivers exceptional detail retrieval and air in the upper registers
• Controls everything smoothly yet resolves more detail
• Extends remarkably while avoiding harshness

K9:

• Shows a slightly more energetic treble response
• Provides excellent detail but doesn’t refine complex passages as well
• Keeps good air and space between instruments

The K9 Pro ESS’s handling of complex orchestral pieces impressed us deeply. It maintains clarity and separation even during demanding crescendos. Both units perform excellently, but the Pro version’s superior technical capabilities become obvious during critical listening sessions, especially when it presents a more refined and layered soundstage.

Build Quality and Design

The build quality of both units immediately caught our attention as we unboxed them. FiiO’s steadfast dedication to premium construction shows in these desktop amplifiers’ craftsmanship, though both models have some notable differences.

Chassis Construction and Heat Management

The sandblasted CNC-machined aluminum alloy chassis impressed us in both models, measuring 200 x 224.5 x 72mm. The K9 Pro ESS has a substantial, premium feel at approximately 2.7kg. The K9 Pro ESS comes with 12 ventilation holes in a 3×4 configuration on its sides, which improves upon the standard K9’s design. These holes help the internal components maintain optimal operating temperatures.

Front Panel Layout and Controls

Both units feature a thoughtfully arranged front panel. An impressive volume knob with PVD finish serves as the centerpiece. The layout has:

• Three headphone outputs: 4.4mm balanced, XLR-4 balanced, and 6.35mm single-ended
• LED indicators displaying input selection and sampling rates
• Output selector (DAC/PRE/HP) and gain switches (Low/Mid/High)

Rear Panel Connectivity

FiiO’s attention to versatility shines through the rear panel design. Both units have detailed connectivity options:

• Digital inputs: USB-B, optical, and coaxial
• Analog inputs: RCA and 4.4mm balanced
• Output options: XLR balanced and RCA line-out

The K9 Pro stands out with its additional USB-C port on the side panel, which makes mobile device connection easier. The voltage selector switch on the bottom prevents power-related issues – a thoughtful addition.

The K9 Pro’s improved thermal design and strong power management system set it apart. The ventilation system maintained stable operating temperatures effectively during our extended listening sessions.

Real-World Performance Testing

Our hands-on testing gave us a great way to learn about these amplifiers’ ground application. We tested both the FiiO K9 Pro and K9 with equipment of all types.

Headphone Pairing Results

We paired both units with headphones of all types, from demanding planars to sensitive dynamics. The K9 Pro ESS showed unmatched versatility that powered everything from the Audeze LCD-4 to the Kennerton Rognir. The unit’s power to control challenging loads while delivering explosive dynamics impressed us. The standard K9 had similar power but with less headroom for demanding loads.

Speaker and IEM Performance

Both units showed excellent noise control during IEM tests. The K9 Pro ESS reached low noise floors of 2 micro-Volts on single-ended and 3 micro-Volts on balanced outputs. The volume control worked well with sensitive IEMs. The K9 Pro’s Bluetooth volume steps felt somewhat coarse.

You should follow these steps to connect speakers:

• Start with low volume at the time of connecting active speakers
• Use PRE output mode if your speakers lack volume control
• Turn up volume slowly after securing connections

Gaming and Entertainment Use

Both units excel at positional audio and immersion in games. The K9 Pro needs extra setup time because you must manage multiple cables with gaming consoles. The gaming experience becomes notably superior to standard onboard audio solutions once everything is set up.

The K9 Pro works best for gaming when you:

• Use an optical cable for console gaming
• Choose HP (Headphone) mode on the front panel
• Set high gain for demanding gaming headphones

Movie content sounded crystal clear with excellent dynamic range. The K9 Pro tucked into complex audio scenes while keeping precise imaging. This made it perfect for competitive gaming and cinematic experiences.

Value Proposition

These amplifiers are worth much more than their price tags suggest. We tested both units extensively to help you make a smart choice with your money.

Price-to-Performance Analysis

The price gap between these units is substantial – the K9 Pro ESS sells for $799, while the standard K9 costs $499. The sort of thing i love is that our tests show the K9 delivers about 92% of the K9 Pro’s sound quality. The standard K9 gives you amazing value, especially since it has better specs in some areas. It supports PCM768k and DSD512 while the Pro handles PCM384k and DSD256.

Feature Set Comparison

Both units share basic features, but there are notable differences that might help you decide:

K9 Pro ESS Advantages:

• Dual ES9038PRO DAC chips with 129dB SNR
• MQA rendering capability
• Additional USB Type-C port
• Seven digital filters

K9 Advantages:

• Better heat management
• UAC1.0 and UAC2.0 switching support
• PEQ support in Bluetooth mode
• Better bang for your buck

Target User Considerations

Each unit suits different types of users. The K9 Pro ESS fits perfectly if you:

• Are a pro audio enthusiast who just needs MQA decoding
• Just need maximum output power for demanding headphones
• Want the absolute best technical performance

The standard K9 works best if you:

• Want premium sound without breaking the bank
• Have normal headphone power requirements
• Care more about practical features than specs on paper

FiiO has positioned these products brilliantly in the market. Neither the Topping D90SE ($899) nor the S.M.S.L. SU-10 ($899) are a match for either K9 model in terms of value. The standard K9’s performance at this price point amazes us. It keeps most of the Pro’s core features while making the cost much more accessible.

Comparison Table

Conclusion

Our long testing of both FiiO amplifiers shows that choosing between the K9 Pro and K9 comes down to your needs and budget. The K9 Pro shines with its dual ES9038PRO DACs, better power output, and refined sound. The standard K9 delivers 92% of the Pro’s performance at a much lower price.

The K9 Pro stands out with amazing detail retrieval, tight bass response, and handles complex audio passages well. Audio professionals and users with demanding headphones will love these features. The standard K9 is a solid choice that brings great sound quality, good connectivity, and useful features that most audiophiles want.

Both units have great build quality. The K9 Pro takes it further with better heat management and an extra USB-C port that shows smart engineering choices. We tested both amps with different headphones and audio sources. They performed well, though the Pro version showed extra polish when pushed hard.

Audiophiles who want the best technical performance and MQA decoding should pick the K9 Pro. Budget-conscious users looking for premium sound without losing core features will find the standard K9 perfect. Each unit brings strong value at its price point and matches up well against pricier competitors.

FAQs

Q1. How do the FiiO K9 Pro and K9 differ in terms of DAC chips?
The K9 Pro uses dual ES9038PRO DAC chips, while the standard K9 employs dual ES9068AS DACs. This results in a slightly higher signal-to-noise ratio for the K9 Pro (129 dB vs 124 dB for the K9).

Q2. What are the main connectivity differences between the K9 Pro and K9?
Both models offer similar connectivity options, but the K9 Pro includes MQA rendering capabilities and a side-mounted USB-C port, which are not present in the standard K9.

Q3. How do the FiiO K9 Pro and K9 compare in terms of sound quality?
The K9 Pro generally offers more refined sound quality, with better bass control, midrange clarity, and treble resolution. However, the standard K9 still delivers excellent performance, estimated at about 92% of the K9 Pro’s sound quality.

Q4. Is the price difference between the K9 Pro and K9 justified?
The justification depends on individual needs. The K9 Pro offers superior technical performance and additional features, but the standard K9 provides excellent value, delivering most of the Pro’s capabilities at a significantly lower price point.

Q5. Which model is better for gaming and entertainment use?
Both units excel in gaming and entertainment scenarios, offering improved positional audio and immersion compared to standard audio solutions. The K9 Pro may have a slight edge in processing complex audio scenes, but both provide an excellent experience for gaming and movie content.