Welcome to viva Analog

Vacuum Tube Ckts /// Guitar-Bass Effects /// DIY pages

Analog Circuit Design and Modeling

JC Maillet (c) 1996 - 2010

R.I.P. Gar Gillies & Ken Fischer


www.viva-analog.com


Thermionic Tech

** NEW ** Low Voltage "Triode Plate-Dynamics" Emulator (posted 19/11/09)

Bias Modulating Tremolo Circuits for Vacuum Tube Amps (11/19/03, update 12/08)

Elliminating Hum in Tube Amps (4/13/04)


Appreciation Pages

Garnet Tube Amps

Garnet Amplifier Variable-Bias Mod

Traynor Tube Amps

** Traynor Amplifier Schematics & Mods Archive **

Fender Tube Amps

Marshall Tube Amps


Selected Tube Projects

'72 Deluxe Restoration/Conversion ('05)

Concert Rig for Ken Hamm ('05)

Traynor mkIII /// Tweed-Reverberization ('04)

Hot-Rodded Fender Combos ('01-'03)

Mesa-Boogie S.O.B. /// Marshall MkII Mod ('01)

JCM900 - Silicon Removal ('97 & '98)

1960 Bassman Restoration

TSL-122 Repair/Mods

'72 Fire Breathing Champ


"Inside Fender and Marshall Tube Amps"

ISBN 0-9684849-0-5

(c) March 2002

Basic research in Vacuum Tube technology // Amp Mods and Tweaks


\\\ Mathematical Explorations ///

A Generalized Algebraic Approach

to Modeling Vacuum Tube Triodes

(1a) Original Glass Audio article - issue 2/98; Pspice Modeling Technique for Vacuum Tube Triodes

Permission to post kindly given by Mr. Ed Dell www.audioxpress.com

(1b) Retyped Glass Audio articlePspice Modeling Technique for Vacuum Tube Triodes ('98)

(2) MATLAB & Pspice Sourcefiles used in this work

(3) My Triode Reference Data RCA 12ax7 // RCA 12at7

(4) Pspice Rectifier Models : 5Y3GT, 5V4GA, 5U4GA, and 5AR4

(reference) Measurement of Nonlinear Transfer Moeller, Gromowski, Zoelzer 2002

(5) Opto-coupler Modeling (*NEW 10/08*) Silonex NSL32-SR3 Static Spice Model


~(: \\\ Rainbow of Sounds /// :)~

DIY Analog Effects

LFB - Little FET Booster *original design* (c) 2009 organic sounding jFET amplifier without the usual gear-sensitivity issues ... MOJO *original design* (c) 2008 class-A tube output stage compression emulator/booster, Super MOJO II *original design* (c) 2008 linear dynamic class-A circuit exaggerator/booster ... click-less Triggered Swell II *original design* (c) 2008 foot activated opto auto-volume circuit with dual mode effect loop ... Vibe+ *original design* (c) 2007 complete make-over of the signal path and control circuitry of the Univibe concept - providing extended depth and timing ... Acoustic 360+ *original redesign* [kit project] - Pro Version ... Envelope Locked Loop *original design* (c) 2007 true dual mode optical compressor/limiter function with threshold and ratio controls ... Nyquist Aliaser [project] *original design* (c) 2005 audio frequency under sampler with narrow-pulse clock ... true anti-phase Stereo-Vibe circuits: (i) Stereo-Vibe 480 *original design* adaptation of Don Bonham's Stereo "Maggie 480" bulb based emulator using Mieda (univibe) class-A phasor stages; (ii) Stereo-Vibe 45 *original design* dual 2-stage light coupled op-amp signal path with original tri-mode (tri-sine-square from one control) super wide range constant amplitude LFO, (iii) Stereo Vibe+ *original design* dual 4-stage light coupled filter using same LFO circuit and signal path style as "45" but with univibe phase shift equivalent caps throughout (based on original theory) ... Range Mistress *original design* full spectrum Si/Ge RangerMaster type booster ... Unicord "Univibe" Phase Shifter *original re-design* [kit project] - extension Mods ... "Harmonic Multiplier" [project] *semi-original design* 4-quadrant multiplier based Squaring "Octaver" circuit with variable linear Mixer for Tube Harmonic Simulations and unique Octavia type sound ... Super "Full-Wave" Octaver [project] *not original at all really* very close approx to f(x)=|x| ... SWR Limiter pedal [project] *original mods* adapted for low supply including two-band active sidechain filtering ... "MutronIII" Filter/Follower [project], *original* Pro version with extensive Mods ... Ranger "ParaExciter MkIII" Filter/Overdriver [project] ... "MXR DynaComp" - Tired Battery Simulator [project] ... EH Small-Stone" Phase Shifter [project] - The "Original" Univibe cap ratios Mod ... PAIA "Infinity+" sustainer circuit re-design [project] ... 4-transistor Pitch-Only Theremin with Line-Out mod [project] ... MXR "Phase45" [project] - Univibing Filters, LED speed Indicator, Vibrato/Phasing mods ... Dan Armstrong "Green Ringer" [project] - Nulling mod ...

Photo: Harry Primate - Missaussaugua Ontario


2008 viva Analog "360+ Pro" Bass Preamplifier-Fuzz


\\\ 2010 viva Analog 360+ DIY Bass Preamp Kit ///

** 2nd Edition RELEASE 07/10 **



\\\ Super Vintage - Mammoth Ivory ///

Organic Tone for Acoustic Guitars



jc -> lynx.net

Copyright JC Maillet (C)1996-2010