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America's most censored book is here!

unseenenemycvr

Unseen Enemy

An Eyewitness Account of the Betrayal of America

Authored by Stegall

A chance encounter with persons associated with espionage activities make me a target of ongoing covert operations. In the course of doing so, my adversaries stir a maelstrom of trouble seemingly significant to the course of prophecy and to the future of the nation.  The truth is stranger than fiction.  Very strange!

Primary sales page:  link, Amazon.com:  link, Amazon.co.uk:  link

For other Amazon sites or if these links break enter my name in Amazon search box.

I will post links to other sales outlets later.

Testimony of Tyranny

Testimony of Tyranny

Testimony of Tyranny

God Disclaims Responsibility for Abnormal Weather

Proof of Censorship

Proof of Censorship

Proof of Censorship





 

Copyright © 2009 through 2016 by Wayne Stegall


Audio Home Page

Circuits or calculations should not be breadboarded until they are proven by SPICE simulation.  Even then breadboard and test a prototype before committing to a final circuit.  Unproven circuits or ideas are for mental stimulation only.  Note also that mistakes usually go unnoticed until I find and fix them; therefore I recommend letting ideas sit for a while before considering them complete.  For this same reason I try to provide proofs where reasonable or possible so that the user of an idea can verify it before use.

First Things


Theory

  • Phono Equalization Calculations  Updated February 6, 2014 .Added schematic and design equations for op-amp based current-input circuit.  Updated March 17, 2014.  Expanded derivation of two stage equalization equations to more easily show how current-input equalization derives from them.  Added more topologies and detail for current input designs..
  • When Is Phase Shift not Phase Shift?  January 2, 2009
  • Linear Phase Sinc Compensation Filter for Zero-Oversampling DACs  January 26, 2009
  • Mathematical Consideration of Some of the Limitations of Digital Audio  May 23, 2009
  • Phono Termination Calculations and Calculator  August 10, 2009.  Updated September 13, 2012  Raised program version to 3.3.0 adding shortcuts for entry of Bessel and Butterworth Q values.
  • Active Inductor Load  Updated March 11, 2010.  Changed designation for MOSFET constant to proper kn.
  • Power Supply Ripple Calculations and Capacitor Size  December 6, 2009
  • Simple Noise Calculations  Updated February 27, 2010.  Recalculated RIAA noise bandwidth by numerical integral.
  • Musical Feedback Amplifiers  Updated November 2, 2010.  Added AD847 to list of Possibly Musical IC Operational Amplifiers and a link to its datasheet.
  • Simple DC Servos  Updated July 21, 2010.  Spice verified.  First order servos reduce amplifier DC offset without fear of oscillation.  Musical Feedback Amplifier example.  Elaborated servo equations to better clarify integrator response.
  • A Musical View of Distortion  August 31, 2010
  • Transfer Curve Shape and Distortion  January 1, 2011.  Multiple bends in transfer functions reduce distortion quality.  Updated January 6, 2011.  Added investigation into distortion masking and made an immediate model correction to same.
  • Flicker Noise Calculations  January 26, 2011.  Noise of unknown origin causes a rise in noise at low frequencies.
  • Managing TIM  February 26, 2011.  Practical means to avoid a difficult-to-measure form of distortion.
  • Distortion Cancelation  May 26, 2011.  Three simple distortion cancelation concepts.  Updated May 31, 2011.  Added SPICE verification of voltage mirrors.  Updated June 8, 2011.  Recommended use of voltage mirror for BJT circuits only for unity gain pending further investigation.  SPICE results problematic with gain, only unity gain producing the desired results.  See text.  Updated June 11, 2011  Added SPICE verification of integer-gain BJT voltage mirror.
  • Optimizing the Class B Emitter Follower  August 5, 2011.  Is current drive better than voltage drive?
  • Local Feedback  August 27, 2011.  Is Local Feedback the same concept as Global Feedback?
  • Apples and Oranges  October 2, 2011.  A simple proof that class-A and class-B distortion specifications are not comparable.
  • Phono Preamp Input Protection  November 3, 2011.
  • Transistor Preference  December 14, 2011.  The effect of transistor choice on distortion performance
  • One-Bend Amplifier  January 31, 2012.  Part 1:  Compare a current-feedback amplifier allowing a one-bend distortion characteristic to its voltage-feedback equivalent.  Updated  March 14, 2012  Added correction concerning output stage transconductance factor and added a link to the next article.
  • Digital Audio Formats  April 18, 2012.  Updated April 19, 2012  Added graph illustrating how oversampling improves analog filter application.  Updated April 20, 2012  Added extra material correcting presumptions contrary to the limitations of the successive-approximation ADC.
  • Feedback Distortion Analysis  August 11, 2012.  Taming the capricious transfer curve.  Updated August 11, 2012.  Added footnote about polynomial representation, improved some wording, added derivation of gain polynomial from transfer curve polynomial, and added an example of long  division.
  • Understanding the S-Domain  October 26, 2012.  Updated October 27, 2012.  Added Q to legend of figure 6 and another link under examples.
  • Delta-Sigma Modulators  January 15, 2013.  Their basic theory of operation.  Updated January 16, 2013.  Corrected some grammar and added an extra phrase of text and graphs of analog FIR filter kernels.
  • Single-slope Safe-area Limiter  March 16, 2013.  And other transistor limiters.  Updated April 5, 2013.  Added an improved component calculation sequence and additional power calculations.
  • Electrical-Mechanical Equivalence  April 27, 2013.
  • Analog is Digital  May 24, 2013.  Quantum mechanics defines quantization of analog signals comparable to that of digital audio.
  • Thermal Design  July 12, 2013.  Part 1:  Thermal design for gainclone and one-bend amplifiers is used to illustrate the presented theory.
  • Thermal Design  August 17, 2013.  Part 2:  Thermal design for one-bend amplifier is used to illustrate theory advanced to include thermal capacitance.  August 23, 2016.  Restored missing subfile to SPICE model.
  • Square Law  September 17, 2013.  How the square-law of field-effect devices arises from physics.
  • Room Effect and Speaker Alignment  December 6, 2013.
  • Differential Equalization  May 27, 2014.  Differential circuit transformation has application to differential RIAA equalization.
  • Perspective  August 16, 2014.  The mathematics of the perception of acoustic distance and the possiblity of altering it with equalization.  Updated August 18, 2014.  Corrected some misspellings and grammar, improved some wording, and completed footnote.
  • Decibels  November 21, 2014.  The calculation and use of decibels in audio.
  • Noise Shaping Music  April 3, 2015.  DSD-like coding inside PCM digital audio content increases its resolution.  Updated May 27, 2015.  Corrected equations 2 and 3 making pole only dependent on b1; the a0 coefficient only affects gain.
  • Digital Phono Equalization  June 6, 2015.  Updated September 1, 2015.  Added capability to digitally equalize a current-input preamplifier.  Updated September 7, 2015.  Added results of an actual test recording.  Updated  May 3, 2016.  Added inverse RIAA functionality to software.
  • Turntable Geometry  October 26, 2015.  Theory, calculator, and protractor useful to setup your turntable's tonearm.  October 26, 2015.  Added a more precise statement about what software will print the protractor.  October 29, 2015.  Added explanation of overhang to the end of the theory section.  Updated November 14, 2015.  Added |φerr/r| graph to calculator to give feedback that calculations are correct.
  • Dual-slope Integrator  January 16, 2016.  Reduce high frequency amplifier distortion.
  • Lossy Compression  February 27, 2016.  How does compressed audio like mp3 work and what effect does it have on sound?  Updated February 29, 2016. Added time anomalies to Analysis of sound effect
  • Butterworth Filter Synthesis  November 18, 2016.  Updated November 25, 2016.  Added highpass bode plot and example of calculation of pole angles and Qs.
  • Chebychev Filter Synthesis  December 31, 2016.
  • State Variable Tone Control  July 14, 2017.

Application

  • Line Level Class A Power Supply  Updated March 11, 2010.  Corrected for improper gfs presumptions.
  • Low Noise 2-Stage All JFET Phono Preamp  Updated July 2, 2010.  SPICE verified.  Recalculated with 48V power supply and RIAA standard gain.
  • A Linear Logarithmic Volume Control  September 29, 2010.
  • Low-noise Hybrid Op-amp/Discrete Phono Preamp  October 29, 2010.  SPICE verified.  Desire discrete output buffer to add neutral euphony to nearly distortionless op-amp preamp.  Updated October 29, 2010  Improved visibility of graphs.  Updated October 30, 2010  Added links to semiconductor datasheets in parts list.  Move class-a bias to connect to positive supply, and verify no operational changes.
  • Cascode Selector  November 17, 2010.  SPICE verified.  Audiophile-grade semiconductor selector for input or other switching.  Updated November 27, 2010 Added power supply recommendations and a schematic for an LED indicator.
  • Cascode Phono Preamplifiers  May 3, 2011.  SPICE verified.  Capacitively coupled cascode enables an easily adjustable single-stage preamp.  Updated March 3, 2012  Added transfer error curve analysis for both circuits.
  • One-Bend Amplifier  March 14, 2012.  Part 2:  Improving important details of a current-feedback amplifier.
  • One-Bend Amplifier  June 6, 2012.  Part 3:  Modified circuit adds a predriver stage.
  • Floating Source-follower Regulator  July 7, 2012.  One-Bend Amplifier Part 4:  Hum injected in stage 2 of amplifier required the design of a useful general purpose voltage regulator.  Updated July 8, 2012.  Added comment about the MOSFET's limited hum suppression capability after equation 11.
  • Warp Filter  September 22, 2012.  Highpass notch filtereliminates dangerous LP warp signals.
  • DAC Cascode   December 1, 2012.  Analog DAC circuit designed with one BJT.  Updated  December 2, 2012.  Added text recalculating a new C4 value for the second circuit under load.  Updated December 7, 2012  Correcting SPICE model error changed distortion results somewhat.  Reworded statement about useful DACs to indicate that the AD1955 will require an NPN design.  Added paragraph on the interpretation of the datasheet.  Updated January 1, 2013.  Added an NPN design and analysis based on the AD1955.  Updated January 2, 2013.  Changed schematics to show how unused DAC outputs should be terminated.
  • Voice Control  October 26, 2013.  Circuit enables adjustable euphonic control.
  • Distortion Grapher  March 5, 2015.  Circuit enables distortion error to be graphed.
  • One-Bend Amplifier  August 20, 2016.  Part 4: Improvements include lower hum
  • Sealed-box Speaker Equalizer  January 14, 2017  Part 1:  Chebychev design methods allow the design of speaker equalizer.  Updated January 14, 2017  Added missing last curly brace not copied with program and added mention of use of SPICE Opus.  Updated January 14, 2017  Added input for user to input his own C1/C2 choice to program
  • Sealed-box Speaker Equalizer  March 18, 2017  Part 2:  Design of equalizer with n-channel JFETs.  Updated March 19, 2017.  Corrected incorrect filenames in program use instructions and added a brief paragraph on buffer design.  Updated March 21, 2017.  Added section Determining speaker parameters.
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Downloads

  • CD Exerciser – Improve your CD player with a homemade test disk  April 20, 2009
  • Op Amp Noise Calculator  Updated January 17, 2011.  Added considerable new program functionality including accounting for flicker noise.
  • Phono Termination Calculations and Calculator  Details in Theory above.
  • FETCurve  June 26, 2011.  A FET parameter calculator.  Updated May 31, 2012.  Added SPICE verification.  Updated program to version 1.1.0 to flag alias error and to show kn for transconductance factor to avoid confusion with SPICE parameter KP.  Updated June 2, 2012.  Updated program to version 1.2.0 adding input checking for numeric entries.  Immediatedly released version 1.2.1 to allow negative number entry.
  • Turntable Geometry  Theory, calculator, and protractor useful to setup your turntable's tonearm.  Details in Theory above.

Obsolete


External Links


Real Stereo program sponsored by TNT-Audio


  • Affordable$$Audio  Internet audio magazine archives, just merged into HiFi Zine below (subjectivist, some advertising)
  • Audiophilia  Internet audio magazine (subjectivist, some advertising)
  • AudioWorld Web Directory  This website has reverted to an Audio Web Directory again for now.
  • AudioXpress  Website of print audio magazine emphasizing DIY (subjectivist/objectivist, some articles on website)
  • Enjoy the Music  Internet audio magazine (subjectivist, some advertising)
  • High-end Audio  The personal audio website of Arthur Salvatore (subjectivist, no advertising).
  • High Fidelity  Internet audio magazine (subjectivist, some advertising)
  • Hi-Fi Choice  Website of print audio magazine (subjectivist/objectivist,  some articles on website)
  • Hi-Fi News & Record Review  Website of print audio magazine (subjectivist,  some articles on website)
  • HiFi Zine  Independent internet audio magazine (philosophy?, some non-audio ads)
  • Positive Feedback  Internet audio magazine (subjectivist, some advertising)
  • Six Moons  Internet audio magazine (subjectivist, some advertising)
  • SoundStage! HiFi  Internet audio magazine (subjectivist, some advertising)
  • Stereophile  Website of print audio magazine (subjectivist,  some articles on website)
  • Stereo Times  Internet audio magazine (subjectivist, some advertising)
  • TNT-Audio  Independent internet audio magazine (subjectivist, no advertising)
  • Ultra High Fidelity Magazine  Website of print audio magazine (subjectivist,  interesting general hifi reading on website, but no magazine articles)