Acoustical simulation

Speaker Directivity Modeler
May 12, 2023

Online simulation of a speaker mounted in an infinite baffle.

Room Boundary Simulator
May 2, 2023

Simulation of early reflections from the floor, ceiling and from the wall behind the speaker. Baffle step and speaker directivity are also simulated.

Noise perception modeler
April 5, 2023

Prediction of the audibility of noise in audio systems with "flat" noise floor from SNR.



Digital audio

Listening test: Quantization noise & bit-depth 🔊 🎧
December 20, 2021

Fortunately, investigation of bit-depth and quantization doesn't require complicated and tiring ABX tests and only takes a few minutes. At the end of the article, there is a short analysis of what 12 bits are enough for.

High-resolution audio vs. 16 bit / 44.1kHz
November 2, 2021

Does high-resolution audio sound better than CD? Investigation of the optimal sampling frequency and bit depth of distribution audio formats.

Dynamic range of MP3 and AAC encoding
August 9, 2018

Measurements of a fixed-point decoder and a floating-point decoder. 16-bit & 24-bit tests.


Loudspeakers & cables

Speaker cable guide
May 14, 2019

Main topics: Calculation of the minimum cross-section. Shielded and twisted speaker cables. Speaker wire plugs. Table with recommended cable length. Calculation of the inductance loss.

Audio interconnect cables explained
February 28, 2019

Brief tutorial about audio interconnect cables.

Frequency response of a speaker cabinet on the rear axis
April 25, 2018

Approximation of the frequency response of a speaker cabinet on the rear axis with a first-order low-pass filter. With this method, the reflection from the wall behind the speaker can be calculated simply and with sufficient accuracy.

Measuring the sound radiation of speaker cabinet walls
November 25, 2017

Measuring the sound radiation of different types of woods used in speaker cabinets. The effect of cabinet damping material on sound radiation.

How to remove internal standing waves from speaker cabinets?
November 21, 2016

The placement of sound absorbing materials is critical to achieve maximum sound absorption in speaker cabinets.


Headphones

Headphones & amplifiers - output impedance, load impedance and frequency response
October 20, 2020

How does high output impedance affect the sound of headphones; some notes on the damping factor; output impedance and nonlinear distortion.


Guitar amplifiers & speakers

Roland Micro Cube (v1) Classic Stack model analysis & measurements
November 27, 2018

Pre & post distortion filter measurements of a classic digital amp modeler.

Tube versus solid state: is tube distortion a myth?
November 9, 2018

Popular misconceptions about tube guitar amplifiers and tube distortion.

Celestion Seventy 80 guitar speaker measurements
February 26, 2019

Measurements for the crazy ones.


Psychoacoustics of sound reproduction

Noise perception, detection threshold & dynamic range
January 17, 2023

What is the "ear-perceived" dynamic range of 16bit/44.1kHz and some older formats? Why is the typical answer ("dynamic range of 16 bits = 96 decibels") wrong? Why doesn't Signal-to-Noise Ratio and "dBA" tell the whole story? What is the dynamic range of an audio system in which low-level signal transmission is affected by noise? - Dispelling the misconceptions about SNR, dynamic range and noise perception... The article also contains a comparison of noise audibility threshold of popular audio formats (16/44k, vinyl, reel-to-reel tape).