FiiO K9 Pro ESSFrom real comments

Verdict distilled from 38 mentions across 12 aspects in comments under product review videos.

Positive sentiment61%
PROS 61%
CONS 39%

Rank based on 38 mentions across 12 aspects

View the verdict as

Buy this if...

  • You want an all-in-one desktop DAC/amp with wide connectivity (balanced, coax, optical, Bluetooth)
  • You value crisp, energetic, highly resolving sound at this price point
  • You want to drive a wide range of headphones and powered speakers from one unit

What users love

Skip this if...

  • You're sensitive to a higher noise floor or need extended sub-bass extension below 20Hz
  • You rely heavily on the FiiO Music app for stable Bluetooth/filter control
  • You want guaranteed long-term reliability, given reports of gain and channel failures

What users complain about

Compare in seconds

Based on user comments

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1Premium
SMSL VMV D2
Natural, non-fatiguing soundMQA and AK4499 chip appealClear upgrade over harsher rivalsUncertain heat outputHigh priceNo sharper sound signature option
SMSL VMV D2
Natural, non-fatiguing sound
MQA and AK4499 chip appeal
Clear upgrade over harsher rivals
Uncertain heat output
High price
No sharper sound signature option
2Premium
SMSL H400
Strong power deliveryReliable alternative to competitorsSound-tuning flexibilityCosts more than cheaper alternativesHigh price
SMSL H400
Strong power delivery
Reliable alternative to competitors
Sound-tuning flexibility
Costs more than cheaper alternatives
High price
3
HiFiMan Goldenwave GA10
Fully Balanced ArchitecturePremium, Understated BuildRich Tube Sound
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Fully Balanced Architecture
Premium, Understated Build
Rich Tube Sound
4Premium
iFi iCAN
Drives almost any headphoneUnique xBass and 3D tuning controlsMusical, layered, engaging soundHigh price questionedOverdamped decay / odd dynamics reportedCannot switch preamp and headphone outputs independently
iFi iCAN
Drives almost any headphone
Unique xBass and 3D tuning controls
Musical, layered, engaging sound
High price questioned
Overdamped decay / odd dynamics reported
Cannot switch preamp and headphone outputs independently
5Budget
SMSL VMV SAP1
Excellent value for moneyDrives demanding headphones with easeExceeds initial expectationsInconsistent regional pricingCheap-feeling volume knobLimited availability at some retailers
SMSL VMV SAP1
Excellent value for money
Drives demanding headphones with ease
Exceeds initial expectations
Inconsistent regional pricing
Cheap-feeling volume knob
Limited availability at some retailers
6Premium
iFi Pro iCAN
Extremely versatile tuning options
iFi Pro iCAN
Extremely versatile tuning options
7Mid
Monoprice Monolith THX AAA 887
Balanced XLR ConnectivitySought for Driving Hard-to-Drive HeadphonesSolid Metal Volume Knob
Monoprice Monolith THX AAA 887
Balanced XLR Connectivity
Sought for Driving Hard-to-Drive Headphones
Solid Metal Volume Knob
8Mid
Creative Sound Blaster E3
Strong Value on SaleGaming Software FeaturesImproved Dynamic RangeFull Price Feels HighUncertain Value vs E5
Creative Sound Blaster E3
Strong Value on Sale
Gaming Software Features
Improved Dynamic Range
Full Price Feels High
Uncertain Value vs E5
9Budget
SMSL RAW-HA1
Strong speaker amp performance
SMSL RAW-HA1
Strong speaker amp performance
10Mid
iFi Hip-DAC
Detailed, engaging sound
iFi Hip-DAC
Detailed, engaging sound
You are here
31Mid
FiiO K9 Pro ESS
Highly resolving, detailed soundVersatile connectivityAttractive, solid build designDebatable value of ESS over AKMMinor usability quirksBuggy FiiO Music app
FiiO K9 Pro ESS
Highly resolving, detailed sound
Versatile connectivity
Attractive, solid build design
Debatable value of ESS over AKM
Minor usability quirks
Buggy FiiO Music app

Who wins on what

Ranked by what users actually praise

Overall Impression

Sound quality is the K9 Pro ESS's biggest strength, described as crisp, detailed, and highly resolving. Users repeatedly describe the ESS as crisp, clear, and energetic, revealing details and orchestral noise they'd never heard before, and outperforming similarly priced DACs like the Gustard X26 Pro in preference despite technical specs. It's praised for driving planars, IEMs, and powered monitors well, and for making entire headphone collections 'open up' at a new level, though a few feel it lacks 'full note quality' compared to alternatives like the Shanling H5.

The ESS vs AKM debate leaves many unconvinced the upgrade is worth the price difference. Multiple commenters who compared both versions say the $150 premium isn't justified, since 90-95% of listeners won't notice a difference, and note the ESS actually has a higher noise floor and less bass extension below 20Hz than the AKM. Some canceled ESS orders in favor of the cheaper AKM, though others feel both versions are worth their respective prices given the AKM's diminishing availability.

Software and occasional hardware reliability issues are a recurring frustration. Owners report the FiiO Music app disconnecting, unreliable filter switching, and Bluetooth dropouts, plus quirks like defaulting to RGB lighting or standby issues interrupting playback. A subset of buyers experienced serious hardware failures including dead channels, gain stage failures, overheating requiring extra cooling, and unexpected reboots, prompting hesitation about future FiiO purchases.

Outdated / Not-accurate data?