WiiM Ultra Review: Budget King of Digital Pre-amps?

For the last two years, the WiiM Pro and Pro Plus have been the "default" recommendation for anyone entering the world of high-fidelity streaming. They offered bit-perfect transport at a price that made the established hi-fi brands look nervous. However, they were always "black boxes"—functional, but utilitarian. The WiiM Ultra changes the narrative, moving from a mere streaming bridge to a legitimate centerpiece of a high-end audio system.

Hardware: The SABRE Difference

The most significant internal shift is the move to the ESS ES9038 Q2M SABRE DAC. While previous WiiM models used AKM chips known for a "velvet" or smoother sound, the ESS implementation in the Ultra provides a noticeable leap in micro-detail and transient response.

• THD+N: -116dB (0.00015%)

• SNR: 121dB

• Sample Rates: Up to 32-bit/384kHz and DSD512 support.

In our listening tests using the Aful Explorer 5+2 and Monolith T6, the Ultra revealed layers in complex orchestral recordings that the WiiM Pro simply smoothed over.

The Connectivity Hub: HDMI ARC and Phono

WiiM listened to the primary complaints of the modern desktop and living room listener. The Ultra adds two massive features:

1. HDMI ARC: You can finally connect your TV directly to your hi-fi system without the latency issues of Optical (Toslink). This turns your 2.0 or 2.1 system into a high-end soundbar replacement.

1. Built-in Phono Stage: For those who want to integrate vinyl without adding another box to the shelf, the Ultra includes a surprisingly capable MM phono input.

Display and User Experience

The 3.5-inch vibrant touchscreen isn't just for show. It provides immediate album art visibility and access to the WiiM Home app's deep feature set, including the 10-band Graphic EQ and Parametric EQ. For the "tinkerer," this is a godsend. You can create specific EQ profiles for your bookshelf speakers to tame the treble or boost the low-end of your beefier towers.

Mobile App

We recognize the lack of Apple airplay in this device and where it is disappointing we still believe it is a very capable device. The app provides good support for Tidal, Amazon Music and Quboz. These can be started within the mobile app and will remain playing should you take a call or leave the house. You can pause the music directly from the front of the device if needed. The room correction and subwoofer sync were very close to our optimal settings with minimal adjustment.

The Subwoofer Management Moat

One area where WiiM currently destroys the competition is in Bass Management. The Ultra features a dedicated Subwoofer output with a fully adjustable crossover (from 30Hz to 250Hz). Testing this against a vintage Velodyne 10 and a new speedwoofer 10s mkii, we were pleasantly surprised on the granular controls available from our smartphone. Dialing in the woofer to blend into our tower speakers was seamless. Most streamers in this price bracket simply send a full-range signal and rely on the sub's internal filter; WiiM gives you total control.

Technical Comparison

When comparing the Ultra to its predecessor, the Pro Plus, the hardware upgrades are significant: