SunAudio Purified 4 Review: Ranked #9 of 87

Last updated: September 10, 2026

The SunAudio Purified 4 ranks #9 out of 87 total Medium Size Bookshelf Speakers for sound quality. See Top Recommended Speakers By Attribute for all the top speaker suggestions.

Prices on this page were last checked September 9, 2026 at 6:54 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.

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#9 SunAudio Purified 4: $3,650 as tested (pair); modular kit, pricing varies by driver/finish configuration SunAudio eBay

Pros: On-axis response is essentially dead flat from 100Hz to 20kHz, staying within about ±1dB through most of the band and widening only to a gentle +1.5dB rise in the top octave. The listening window curve tracks on-axis almost exactly, meaning off-axis output stays consistent rather than diverging. Both directivity index curves rise smoothly and monotonically from the bass straight through to 20kHz with no bumps, dips, or discontinuities - a sign of very well-integrated driver-to-driver handoff from the beryllium-dome tweeter. Early reflections and sound power both decline smoothly with frequency, with no resonant peaks anywhere in the response. The manufacturer’s own preference-score modeling comes out to 6.65 unequalized (rising to 9.36 with an ideal subwoofer) with a frequency deviation of just 0.8dB across 300Hz-5kHz - genuinely flagship-tier numbers for a 4-inch woofer design. Distinctive modular build: separate CNC-machined aluminum enclosures for the Purifi 4” woofer and BlieSMa T25A beryllium-dome tweeter, mounted on their own tripod stand, with cone-material and finish options.

Cons: A 4-inch woofer means real bass extension is limited - -3dB around 71Hz and -10dB around 53Hz - so a subwoofer is needed for anything below the low-100s. Measured sensitivity of 84.4dB is on the low side, meaning it needs more amplifier power than more efficient designs to reach the same volume. This is manufacturer self-measured data with no independent third-party review, so there’s no outside verification of distortion, unit-to-unit consistency, or how the reference crossover performs outside SunAudio’s own lab. The modular two-sphere design and tripod stand is unconventional, and pricing is steep for such a small woofer given the niche, boutique nature of the brand.

How it compares: Just above it: Arendal 1961 Monitor - $2500 cheaper, 1.5Hz higher bass extension (-3dB). Just below it: Ascend Acoustics Luna V2 Mini-Monitor Titan - $2752 cheaper, 2.4Hz lower bass extension (-3dB).

Bass Extension (-10dB)53Hz (measured, manufacturer spinorama data)
Bass Extension (-3dB)71Hz (measured, manufacturer spinorama data)
DriversBlieSMa T25A beryllium-dome tweeter (own CNC aluminum enclosure), Purifi 4" Ultra Low Distortion Extended woofer (PP-coated paper/fiber cone)
Impedance4 ohms
Power Handling200W long-term max (woofer)
Sensitivity84.4dB (2.83V/1m, measured, manufacturer spinorama data)
Woofer Cabinetsealed, separate spherical driver modules on tripod stand