Diffusion, primarily. The 25-grid QRD geometry scatters mid/high reflections (500 Hz – 4 kHz) in 25 different directions instead of soaking them up. You'll see absorption coefficients above 1.0 in the test data because the panel also dissipates a portion of the energy as friction inside the wells — but the dominant behavior is scattering, not absorbing. Pair with foam or bass traps if you also need absorption.

For a small home studio (under 150 sq ft / 14 m²): 2 panels on the rear wall is the highest-impact placement. For a control room or treatment room: 4 panels — rear wall pair plus ceiling pair. For a live room: 6+, distributed around the space. One panel will measurably reduce flutter; coverage scales the effect.

No — and nothing this thin will. STC 27 is a measurement of how this panel handles sound that hits it; it does not mean your neighbors will stop hearing you. Soundproofing (transmission loss between rooms) requires mass, decoupling, and sealed gaps — usually mass-loaded vinyl, double drywall, and resilient channels. KK1201 is room treatment, not soundproofing.

Three things. (1) Material — KK1201 is real solid lumber, not MDF or veneered particle board. You can feel the 15.4 lb / 7 kg weight in your hands. (2) Geometry — the 25 wells are cut to QRD-derived depths, not just decorative. (3) Published test data. We measured this in an accredited chamber and publish the full frequency curve. Most cheap diffusers publish nothing because the numbers wouldn't justify the price.

Effective scattering and absorption from 500 Hz to 4 kHz — voice, snare, vocals, guitar, cymbals, the range where flutter echo lives. Below 250 Hz the panel is mostly inert. If you have low-frequency room modes or boomy bass, you need bass traps (different product, different physics).

15.4 lb / 7 kg. Use four wall anchors rated for at least 20 lb / 9 kg each for safety margin. Drywall anchors (toggle or self-drilling) work for most homes; into a stud is even better. The panel has mounting points on the back — drive screws through them into the anchors. Don't hang it on adhesive strips. This is real wood, not foam.

Natural lumber finish only, as shown. The wood can be refinished — sanded and stained — if you want to match a specific room aesthetic. We do not recommend painting it; paint fills the diffusion wells and dulls the scattering pattern.

Handling time is 1–2 business days. Standard shipping is 7–14 days to the US and most countries (free worldwide on orders over $99). Express is 7 days or less. 100-day returns and replacement guarantee on every order. Ships from our nearest warehouse (US, EU, AU, Asia).