SMSL SU-9 Ultrachat_bubble_outlineFrom real comments

The AK4499EX chipset delivers standout, reference-level sound. Commenters single out the AK4191/AK4499EX pairing as a genuine step up from ESS Sabre chips, with one user recalling being told this AKM combo sounds better than comparable Sabre DACs. Direct comparisons against the SMSL DO300 found the SU-9 Ultra's background noticeably darker and its overall presentation preferable, which listeners speculated came from a stronger power section rather than the chip alone. Pairings with amps like the Topping L50 or Aune S17 Pro produced glowing reactions, even through budget-friendly headphones such as the HiFiMan HE400se, suggesting the DAC scales well across different downstream gear.

It needs a separate amp, and reliability reports vary. Several commenters point out the SU-9 Ultra is DAC-only, with no onboard headphone amplifier, so it must be stacked with something like an SH9, L50, or AO200 MKII before it can drive headphones at all. One user found this pairing requirement confusing when first setting up cables with an older system. Separately, one buyer reported their unit died after just two hours, leaving only a red LED and no response to the remote, raising questions about consistency in build quality despite otherwise strong sonic performance from the chipset itself.

SMSL's sprawling, overlapping lineup makes shopping confusing. Multiple commenters struggle to differentiate the SU-9 Ultra from siblings like the SU-9 Pro, DO300, DO300EX, and the newer D400 Pro and RAW-DAC1, all sharing similar chipsets at nearby price points. One noted SMSL alone has over twenty overlapping DAC models competing with each other. Buyers also weigh it against Topping's similarly chipped E70 Velvet, which is priced lower, and wish for missing features like HDMI input. This flood of near-identical releases leaves shoppers needing detailed comparisons before committing to the SU-9 Ultra over its many stablemates.