About Diffusers Guide
How QRD sound diffusers are sized and placed.
What this site covers
Diffusers Guide is an acoustics reference for sound diffusion in small rooms. It covers the mathematics behind quadratic residue diffusers and the practical constraints that decide whether one belongs on a particular wall.
- QRD well-depth sequences and prime selection
- Design frequency, well width and the high-frequency cutoff
- One-dimensional wells against skyline and binary amplitude panels
- Placement, mounting distance and periodicity across a wall
- Managing early reflections in a small room
- Build tolerances that matter and ones that do not
The two entry points are the QRD diffuser sizer, which generates a well depth sequence from a design frequency, and the well depth reference behind it. Everything here is arithmetic you can check, not product recommendations.
5 articles are published so far. New ones are announced on the RSS feed.
How these articles are produced
Articles here are researched from primary sources: vendor and project documentation, published standards and specifications, research papers and preprints, and measurements published by whoever took them. Drafts are produced with AI assistance and then edited against those cited sources before anything is published.
No article on this site is based on first-hand testing in a private lab, and nothing here should be read as a measurement report of its own. Where a number appears, it comes from a source that is named, so you can check the original instead of taking this site's word for it.
Everything is published under a single editorial byline. That byline is a publishing identity for the site, not a claim about a named individual, and it does not carry professional credentials.
Corrections
Corrections are welcome. If something here is wrong, out of date, or attributed to the wrong source, email [email protected] with the page address and what it should say. Substantive corrections are made in the article itself rather than quietly dropped.
How this site is funded
This site currently runs no affiliate links, sponsored posts, display advertising or paid placements. If that changes, the disclosure page will say so.
Contact
Email: [email protected]
Site: diffusersguide.com
Published by: Diffusers Guide Editorial
See also the privacy policy, the terms of use, and the editorial disclosure.