Acoustics 201 : Loudspeaker measurements
4.4 (285 ratings)
Course Ratings are calculated from individual students’ ratings and a variety of other signals, like age of rating and reliability, to ensure that they reflect course quality fairly and accurately.
1,357 students enrolled

Acoustics 201 : Loudspeaker measurements

Learn how to make frequency response and impedance measurements and set up the foundation for designing crossovers.
4.4 (285 ratings)
Course Ratings are calculated from individual students’ ratings and a variety of other signals, like age of rating and reliability, to ensure that they reflect course quality fairly and accurately.
1,357 students enrolled
Created by Marius Tanasescu
Last updated 1/2020
English
English
Current price: $69.99 Original price: $99.99 Discount: 30% off
5 hours left at this price!
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This course includes
  • 3.5 hours on-demand video
  • 5 downloadable resources
  • Full lifetime access
  • Access on mobile and TV
  • Certificate of Completion
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What you'll learn
  • Measure frequency response of a speaker or sound system.
  • Make distortion measurements.
  • Measure impedance and create impedance plots.
  • Measure the Thiele / Small parameters of a speaker driver.
  • Create FRD and ZMA files for crossover design applications.
  • How to make anechoic frequency response measurements in your own room.
Requirements
  • Basics on acoustics and enclosure design.
  • Microphone designed for measuring.
  • Device for impedance and other electrical measurements.
Description

Learn how to measure frequency response

The first thing you will learn from this course is to measure the frequency response of a certain speaker driver, loudspeaker or sound system. The difficult part is to get an anechoic response without an anechoic chamber. Using different measuring techniques and with the help of intuitive software, you will learn how to measure the full frequency bandwidth anechoically in your own living room. This will help you set up your audio system using measured data, or it can be used to design crossovers for your particular DIY loudspeaker.

A little bit of electrical engineering

A sound system is a combination of both acoustical and electrical parts. You will also learn how to measure impedance and create impedance plots. Measure different electrical components like capacitors, inductors and resistors. Also, if you have an unknown speaker driver you will learn how to measure the Thiele / Small parameters without much fuss.

Dip your feet into crossover design

While this course will not teach you how to design a crossover, it will show you how to create FRD and ZMA files. These are frequency response and impedance files which are used in crossover design apps. At the end of the course I will show you how to load these files into such program, and tryout different circuits and see how adding crossover components behave. A comprehensive course about crossovers will be released in the near future.

Do I need certain equipment?

Yes, you will need 2 core pieces of gear :

  • A measurement microphone (like miniDSP UMIK-1).

  • A device for measuring impedance (like Dayton Audio DATS v2 (recently released v3 as of 2020).

These are roughly 100$ each, but you will get a more comprehensive list of the equipment needed inside the course. With alternatives that you can buy, or more cheaper options. Also, some accessories that will make your life easier are included in the list.

Software option

For the different acoustical measurements we are going to use Room EQ Wizard (or REW). This is a free to use software. Usually, acoustics software are quite expensive and difficult to follow. However, REW is free and quite intuitive to use. Pretty much a complete package. It only misses one function, which I consider important. Don't worry, we're are not going to step up to those complicated application. I devised an Excel spreadsheet which handles this shortcoming. You will find the spreadsheet inside the course.


Nov 2018 Update - Added English subtitles.

June 2019 Update - Corrected a measurement error for the 3-way speaker and added more info to that section

Jan 2020 Update - Update the equipment list

Who this course is for:
  • Audiophiles who want to learn more about sound and speaker systems.
  • DIY-ers who want to build their own loudspeakers.
  • People who want to set up their audio gear using measurements.
  • People who want to set the foundation for learning how to design a crossover.
Course content
Expand all 39 lectures 03:30:38
+ Setup
5 lectures 18:15
UMIK-1 wiring diagram
02:08
Dayton Audio microphone wiring diagram
02:33
Calibration file
05:33
UMIK-1 - Room EQ Wizard setup
05:09
Dayton Audio microphone - Room EQ Wizard setup
02:52
+ Measurement theory
3 lectures 14:13
Measurement techniques and Far field explained
07:42
Near field
04:19
Half space and Ground plane
02:12
+ 2-way speaker measurement
12 lectures 40:30
Presenting the setup
04:27
Measuring distances
01:48
REW Interface 2020 Update
01:37
Far field mid-bass
07:27
Far field tweeter
02:48
Near field mid-bass
03:29
Near field port
02:00
Error, heads-up!
02:34
Combine mid-bass + port
03:07
Box diffraction for near field measurement
05:12
Splice near field with far field
04:04
Create FRD files
01:57
+ 3-way speaker measurement
4 lectures 37:22
Presenting the 3-way speaker
02:24
Presenting the 3-way measurement process
07:12
Raw measurements
09:39
Processing of the measurements
18:07
+ Other acoustical measurements
3 lectures 34:11
Speaker full frequency response - anechoic
11:47
Speaker full frequency response - at listening position
11:37
Distortion measurements
10:47
+ Electrical measurements
4 lectures 25:38
Presenting DATS v2
02:48
How to measure the Thiele / Small parameters
13:00
How to create ZMA files
05:17
Measure electrical components
04:33
+ XSim
4 lectures 23:03
XSim presentation
07:33
Acoustical offset - measurements
08:36
Acoustical offset - processing of data
03:52
XSim - finishing touches
03:02