audioXpress 2021 Back Issues on CD

audioXpress 2021 Back Issues

Volume 52
Issue 1
January 2021
FROM THE EDITOR’S DESK—Celebrating a Double Anniversary, by J. Martins, p. 4
MARKET UPDATE—Drivers, Speakers, and Transducers: Optimization of the Species, by J. Martins, p. 8
Electrostatic Pure Silicon Microspeakers for Wireless Earbuds, by Hermann Schenk and Lutz Ehrig, p. 26
Bass Shakers and Tactile Sound, by Mike Klasco, p. 30
SOUND CONTROL—Cone Loudspeaker Radiation and Directionality, by Richard Honeycutt, p. 40
AUDIO SCOPE—Simple Improvements to a Recent Audio MFB Filter Lowers Harmonic Distortion, by Michael Steffes, p. 46
Four Digital Stylus Force Gauges, by Gary Galo, p. 50
Vanderveen Trans-SE10 Secrets, by Menno van der Veen, p. 58
The Live-Edge Dipoles, by Perry Marshall, p. 68
Getting Started with Automotive Audio Bus (Part 4): Designing and Building Systems, by Brewster LaMacchia, p. 76

Volume 52
Issue 2
February 2021
FROM THE EDITOR’S DESK—An Audio Renaissance, by J. Martins, p. 4
MARKET UPDATE—From Home to the World: Microphones Get Essential Status, by J. Martins, p. 8
MARKET UPDATE—Enabling Voice Capture and Developing for Voice Interfaces, by J. Martins, p. 22
Why Thousands of Virtual Microphones Matter: The Impact of Acoustic Spatial Resolution in a 3D Space, by Erica Yorga, p. 34
AUDIO SCOPE—Design Considerations Imbedding a High-Output Buffer Inside an Op-Amp Loop, by Michael Steffes, p. 40
Widex Moment mRIC RD Hearing Aid, by Brent Butterworth, p. 44
The Science and Physics of High-End Mic-Preamp Design (Part 1): Principal Mechanisms for Audio Designers: Engineering the Sound of Silence, by Mike Meechan, p. 52
X-Altra Moving Coil/Moving Magnet RIAA EQ Preamplifier (Part 1): Design Overview and MC Preamplifier, by Andrew C. Russell, p. 60

Volume 52
Issue 3
March 2021
FROM THE EDITOR’S DESK—Audio Sensing in 2021, by J. Martins, p. 4
MARKET UPDATE—Distributed Testing: Changing Processes for Remote Collaboration, by J. Martins, p. 8
QuantAsylum: A Real-World View of Test and Measurement, by David Logvin, p. 24
The Lab Bench of 2021: Virtins Multi Instrument Measurement Software: The Research, by Stuart Yaniger, p. 32
AUDIO SCOPE—Very Low Distortion, Greater Than 400mA Output Composite Amplifier Headphone Driver, by Michael Steffes, p. 40
The Science and Physics of High-End Mic-Preamp Design (Part 2): Principal Mechanisms for Audio Designers: Minimizing Noise and Distortion While Maximizing Headroom, by Mike Meechan, p. 46
Clever Engineering, by Ethan Winer, p. 52
X-Altra Moving Coil/Moving Magnet RIAA EQ Preamplifier (Part 2): MM Preamp, System Gain Amplifier, Filter, PSU, and Measurements, by Andrew C. Russell, p. 56
HOLLOW-STATE ELECTRONICS—Souped-Up Practice Amps, by Richard Honeycutt, p. 62

Volume 52
Issue 4
April 2021
FROM THE EDITOR’S DESK—Enhanced Audio Quality Frontiers, by J. Martins, p. 4
MARKET UPDATE—Unifying Communications with Amplified Intelligence, by J. Martins, p. 8
Speaker ID Technology, by Vikrant Singh Tomar, p. 18
MARKET UPDATE—True Wireless Earbuds Evolving Toward Hearables, by J. Martins, p. 22
The Evolution of True Wireless Stereo, by Jean-Marc Luneau, p. 30
SOUND CONTROL—One Traditional Way to Increase Loudspeaker Directionality, by Richard Honeycutt, p. 38
AUDIO SCOPE—Improving the Input Noise Model for High Output Current Dual Headphone Driver, by Michael Steffes, p. 44
Measuring Vibration with Piezoelectric Sensors (Part 1): The Research, by George Ntanavaras, p. 48
The Science and Physics of High-End Mic-Preamp Design (Part 3): Considering the IC Options, by Mike Meechan, p. 56
The Best of Two Worlds: An Old-Fashioned Tube Amp and Multilevel Class-D Hybrid DIY Bass Guitar Amplifier Project, by Jens Tybo Jensen, p. 62

Volume 52
Issue 5
May 2021
FROM THE EDITOR’S DESK—A New Window for Vacuum Tubes, by J. Martins, p. 4
GLASS AUDIO—The Original Western Electric 300B Vacuum Tube: Now Shipping Worldwide, by Richard Honeycutt, p. 8
GLASS AUDIO—Using Chaffee’s Method of Load Lines, by Scott Dorsey, p. 14
GLASS AUDIO—Experimenting with Tube Sound, by Bill Reeve, p. 20
GLASS AUDIO—The Cranberry: A Versatile Stereo Vacuum Tube Amplifier, by Bruce Heran, p. 26
AUDIO SCOPE—Determining the Real Output Current for Op-Amps and Fully Differential Amplifiers, by Michael Steffes, p. 36
Measuring Vibration with Piezoelectric Sensors (Part 2): Design and Construction, by George Ntanavaras, p. 40
Noise Is Everywhere—Even in MC Input Transformers (Part 1): A Special Survey for Skeptics, by Burkhard Vogel, p. 48
The Science and Physics of High-End Mic-Preamp Design (Part 4): Different Approaches, by Mike Meechan, p. 54
HOLLOW-STATE ELECTRONICS—Vibrato and Tremolo, by Richard Honeycutt, p. 60


Volume 52
Issue 6
June 2021
FROM THE EDITOR’S DESK—A Glimpse of the Future, Inside a Car, by J. Martins, p. 4
MARKET UPDATE—Tech for the Automotive Framwork, by J. Martins, p. 8
The Changing Automotive Environment in 2021, by Roger Shively, p. 20
Vehicle Electrification and Active Noise Cancellation: The Driving Forces Behind Innovation in Future In-Vehicle Infotainment (IVI) Systems, by Krunal Maniar, p.28
SOUND CONTROL—Using Line Arrays to Control Directivity, p.32
KEF LS50 Meta Loudspeaker: A Material Improvement, by Oliver Masciarotte and Kent Peterson, p. 38
Measuring Vibration with Piezoelectric Sensors (Part 3): The Piezoelectric Amplifier, by George Ntanavaras, p. 48
Noise Is Everywhere—Even in MC Input Transformers (Part 2): Additional Proof for the Skeptics, by Burkhard Vogel, p. 56
The Science and Physics of High-End Mic-Preamp Design (Part 5): The Best Practice, by Mike Meechan, p. 62

Volume 52
Issue 7
July 2021
FROM THE EDITOR’S DESK—Multiple Ways to Amplify, by J. Martins, p. 4
Nuheara IQbuds2 MAX Hearing-Assist Earphones: Digitally Enhanced Hearing Devices, by Brent Butterworth, p. 8
NAD Electronics M33 Masters BluOS Streaming DAC Amplifier: The Complete Wireless Package for a Wireless Life, by Stuart Yaniger, p. 16
MARKET UPDATE—The Multiple Faces of Amplification Evolution, by J. Martins, p. 24
MARKET UPDATE—Professional Power Amplifiers: A Market in Recovery, by James Kirby, p. 38
The DH-220C MOSFET Power Amplifier (Part 1): The Circuit, by Bob Cordell and Rick Savas, p. 40
A New Type of Amplifier for Direct Driving Loudspeakers (Part 1): Theory Behind the Design, by Paul Marchese, p. 50
Low-Distortion Voltage-Controlled Floating Resistor, by Dimitri Danyuk, p. 56
HOLLOW-STATE ELECTRONICS—Negative Feedback Amplifier Circuits, by Richard Honeycutt, p. 62

Volume 52
Issue 8
August 2021
FROM THE EDITOR’S DESK—Making Acoustics Personal and Safe, by J. Martins, p. 4
MARKET UPDATE—Acoustical Solutions Round-Up 2021: A Growing Awareness of Acoustics!, by J. Martins, p. 8
Acoustic Room Treatments: Taming the Gorilla, by Thomas Perazella, p. 22
An Introduction to Measuring Rooms, by Ethan Winer, p. 32
SOUND CONTROL—Zooming Toward Better Online Audio, by Richard Honeycutt, p. 40
Audio Precision APx517B Acoustic Audio Analyzer, by David Logvin, p. 44
Parameter Estimation and Box Simulation with Speakerbench (Part 1): Model Parameter Comparisons, by Claus Futtrup and Jeff Candy, p. 52
The DH-220C MOSFET Power Amplifier (Part 2): Construction and Testing Instructions, by Bob Cordell and Rick Savas, p. 56
A New Type of Amplifier for Direct Driving Loudspeakers (Part 2): Feedback and Power, by Paul Marchese, p. 62

Volume 52
Issue 9
September 2021
FROM THE EDITOR’S DESK—Beyond Stereo, Speakers and Reproduced Sound, by J. Martins, p. 4
Parasound Halo JC 5 Stereo Power Amplifier: Traditional Goodness, by Oliver A. Masciarotte and Stuart Yaniger, p. 8
MARKET UPDATE—New Ways to Formulate Speakers, by Mike Klasco, p. 18
The Tetrahedral Test Chamber Story (Part 1): Recognizing the Need for Consistent Measurements, by Geoff Hill, p. 26
Parameter Estimation and Box Simulation with Speakerbench (Part 2): Introducing Speakerbench, by Claus Futtrup and Jeff Candy, p. 34
Roger Russell (1935–2021): A Lifetime of Passion for Sound, p. 40
The Sound of a Column, by Roger Russell, p. 44
Dual Speaker Columns, by Ken Bird, p. 50
Central-Channel Upmixer Delivers Stereo Nirvana, by Peter H. Lehmann, p. 54
HOLLOW-STATE ELECTRONICS—The Development of Hollow-State Home Music Systems, by Richard Honeycutt, p. 62


Volume 52
Issue 10
October 2021
FROM THE EDITOR’S DESK—Home Theater and Home Entertainment, by J. Martins, p. 4
USound Megaclite 4.0 UH-R2040 MEMS Earphones, by Brent Butterworth, p. 8
MARKET UPDATE—Raising the Bar on Residential Entertainment, by J. Martins, p. 14
The Complete Linear Audio Library on USB, Review by Gary Galo, Bob Cordell, and Dimitri Danyuk, p. 28
SOUND CONTROL—A Tale of Speakers in a Room, by Richard Honeycutt, p. 32
Ultra-Linear: Why It Works And When It Will Not (Part 1): The Fundamental Questions, by Morgan Jones, p. 38
Cascodes, Folded Cascodes, and Current Mirrors (Part 1): Cascodes and Folded Cascodes, by Morty Tarr, p. 44
Refurbishing Altec Lansing Vintage Speakers, by Bruce Heran, p. 50
The Tetrahedral Test Chamber Story (Part 2): Consistent Loudspeaker Measurements, by Geoff Hill, p. 56
HOLLOW-STATE ELECTRONICS—Effects of Negative Feedback, by Richard Honeycutt, p. 60

Volume 52
Issue 11
November 2021
FROM THE EDITOR’S DESK—What’s Old Is New Again, by J. Martins, p. 4
SPL Phonitor One d Headphone Amplifier System: Entering the Matrix, by Stuart Yaniger, p. 8
MARKET UPDATE—DSP Evolution: Audio Processing Powered by AI, by J. Martins, p. 18
MARKET UPDATE—Automotive Audio: Interior Car Acoustics and DSP, by Roger Shively, p. 28
A DSP Audio Processor at Heart, by Al Clark, p. 34
SOUND CONTROL—From Open Office to A/V Recording Complex, by Richard Honeycutt, p. 38
Ultra-Linear: Why It Works and When It Will Not (Part 2): Some Interesting Conclusions, by Morgan Jones, p. 44
Cascodes, Folded Cascodes, and Current Mirrors (Part 2): Current Mirrors and Line Stages, by Morty Tarr, p. 50
The History of the American Magnetic Head Industry, by Scott Dorsey, p. 58

Volume 52
Issue 12
December 2021
FROM THE EDITOR’S DESK—A New Chapter in Audio Development, by J. Martins, p. 4
MARKET UPDATE—The Self-Calibrating Loudspeaker, by J. Martins, p. 8
MARKET UPDATE—The Arrival of Spatial Room Correction Technology, by Lars-Johan Brännmark, p. 20
Dayton Audio DAX88, An Eight-Source, Eight-Zone Distributed Audio Matrix Amplifier: Setting Up a Whole-House Audio System, by Thomas Perazella, p. 24
Directivity Measurement of In-Wall Loudspeakers, by Christian Bellmann, Ruben Hauschild, and Mattia Cobianchi, p. 30
Improved Loudspeaker Crossover: For the Parts Express “Solstice” Kit, by Richard Modafferi, p. 36
SOUND CONTROL—Miking the Audience, by Richard Honeycutt, p. 43
Thinking About DC Power Supplies (Part 1): Circuits Used as Potential Power Sources, by Frans de Wit, p. 46
Cascodes, Folded Cascodes, and Current Mirrors (Part 3): Using a Test Circuit, by Morty Tarr, p. 52
Simple Xtal-Based Motor Control for Turntables, by Michel Nieuwenhuizen, p. 58
HOLLOW-STATE ELECTRONICS—Sbuminiature Tubes and Effectrode Pedals, by Richard Honeycutt, p. 62