Killahertz Acoustics
Domestic
audio and acoustics a collection of practical and accessible articles and tools.
Room Treatment.
Practical Domestic Room Acoustics.
This is a
practical and approachable article concerning the application of acoustical treatment
in a domestic environment. Primarily concerned with 2-channel stereo
reproduction, and rooms of shared domestic function, the article describes the
need for, and use of, low-impact OEM and domestic-equivalent room treatment.
(This is a Microsoft Word document that will open in your browser window
266kB)
(This is a zipped version of the article available to download in zip
format 118kB)
An Introduction to Room Acoustics Theory.
A comprehensive introduction to the subject of room
acoustics. Introductory but comprehensive
theory complements illustrated practical DIY room treatments. From modal room response to specular reflection response and
calculation. Includes a Microsoft Excel spreadsheet,
which calculates axial room modes and analyses their effect, giving a visual
indicator of potential room mode problems. The spreadsheet also includes
a section on room treatments formulae, allowing for easy calculation of DIY
treatments.
(This is a Microsoft Word document that will open in your browser window
138kB)
(This is a Microsoft Excel spreadsheet that will open in your browser
window 129kB)
(This is a zipped version of the article and spreadsheet available to
download in zip format 96kB)
[PLEASE
NOTE THAT THE MODECALC EXCEL SPREADSHEETS USES MACROS THEY ARE ESSENTIAL
FOR THE CORRECT OPERATION OF THE SPREADSHEET. THEYARE GUARANTEED VIRUS-FREE AT
THE TIME OF UPLOADING]
Helmholtz Resonant Absorber.
A two-page article (including illustrations and
embedded test results) hosted by Audioholics regarding the theory,
practical design, and in-room tuning of an Helmholtz
Resonant absorber. An interesting (and readily replicable) DIY project
regarding this demonstrably effective narrow-band bass trap.
(This is a link to the article on the Helmholtz Resonant Absorber, which
is hosted on the Audioholics website)
Loudspeaker/Subwoofer Design.
The Fundamentals of Transmission Line Enclosure Design.
An introduction to the theory and design of
Transmission Line Loudspeaker/Subwoofer enclosures. Including numerous illustrations, formulae, and
guidelines borne of design experience, the article is approachable to all
levels of experience, including novice designers. Yet, whilst introductory in
nature, all aspects of design are covered. This not only enables reasonably
complex design (without recourse to additional information or modelling
software), but serves as a grounding for further study.
(This is a Microsoft Word document that will open in your browser window
340kB)
(This is a zipped version of the article available to download in zip
format 256kB)
Audio Principles.
Crossovers and Filters.
A two-part introduction to the theory and design of
passive crossovers. Including
numerous illustrations and formulae the article will guide the reader through
the theory behind, the application, and the design of high, low, and bandpass filter designs up to a practical 2nd
order (12dB/Oct).
(This is a Microsoft Word document that will open in your browser window
113kB)
(This is a zipped version of the article available to download in zip
format 33kB)
Equalisation.
An
introduction to the theory and application of graphic and parametric
equalisation. Includes
useful information on ISO octave spacing (10, 15, and 30 bands), and an
illustrated explanation of the theory and application of filter Q.
(This is a Microsoft Word document that will open in your browser window
83kB)
(This is a zipped version of the article available to download in zip
format 29kB)
Tools and Calculators.
Cable Design Calculator.
A comprehensive Microsoft Excel spreadsheet designed initially to debunk
audio cable mythology. In doing so, however, it naturally has use in cable
design where parameters such as inductance, capacitance, characteristic
impedance, skin effect, etc, are considerably more valid. Other calculations
include resistance, cable area, volt drop, velocity of propagation, etc.
**please note that the calculator is under
almost constant revision with reference to accuracy and content email any
questions/points**
(This is a Microsoft Excel spreadsheet that will open in your browser
window 139kB)
(This is a zipped version of the spreadsheet available to download in
zip format 38kB)
[PLEASE
NOTE THAT THE CABLECALC EXCEL SPREADSHEETS USES MACROS THEY ARE ESSENTIAL
FOR THE CORRECT OPERATION OF THE SPREADSHEET. THEYARE GUARANTEED VIRUS-FREE AT
THE TIME OF UPLOADING]
Links.
Noteworthy
audio forums and sites.
Talk Audio
....The
Hifi Wigwam
..The
AV Forums
The
RPG Europe
....UK-based arm of
RPG, OEM acoustical product manufacturer and retailer.
Audioholics
....An excellent resource for
objective hardware reviews and technical audio and acoustic articles.
Art
Ludwig
.An excellent resource for audio and acoustic science articles.