All Acoustical Simulation Audio Cables Digital Audio Guitar Headphones Loudspeakers Psychoacoustics

Psychoacoustics of sound reproduction

Nonlinear distortion: measurements with complex signals, audibility questions, model of music
July 18, 2023

Modeling polyphonic music with complex tones for worst-case testing.

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

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...

Digital audio

Demonstration of sampling (interactive chart)
June 4, 2023

Sampling theory made simple. Online simulation of sampling, demonstration of aliasing, oversampling.

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

12-bit, 14-bit and 16-bit noise floor comparison.

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.

Acoustical simulation

Speaker Driver Simulation With Room Response
July 24, 2023online

Extended version of Speaker Directivity Modeler with room response calculation from radiated sound power and free-field response (direct sound).

Speaker Directivity Modeler
May 12, 2023online

Online simulation of a speaker with a flat, completely rigid diaphragm mounted in an infinite baffle.

Room Boundary Simulator
May 2, 2023Windows

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, 2023online

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

Tools for studying speaker directivity
September 9, 2019Excel

Excel workbooks for studying speaker directivity. Polar chart, frequency response vs. angle, sonogram (color map).

Sound waves between two walls
August 12, 2019Excel

Simulation of a sound source between two parallel walls. Frequency response, CSD (waterfall), impulse response.


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 & 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.

Audio 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
February 28, 2019

Brief tutorial about audio interconnect cables.

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.