This is a long project and will take months due to my limited spare time, but if people show an interest it will motivate me to devote more effort to it on weekends -) Meanwhile, I intend to make one with RM4 or RM6 inductor cores and AWG 42 wire (the same size used for guitar pickups), and see if I can get similar sound response. I would very much like to do that, so if you know anyone who has one of these in SoCal please contact me!. Then I could calculate very accurate gyrator circuit elements to precisely replicate the original inductors using opamps. I don't own one of these amps, but if I could get my hands on one, I would do a thorough analyses of the inductors to find their ESR and EPC characteristics, and find out if the cores saturate easily (which would add some distortion to the sound) or if they are gapped to prevent saturation (which would increase the number of turns necessary and bump up the series resistance and parallel capacitance).

I used to look at the Mesa amps and wonder why they only used a 5-band EQ, but I realized that if it was indeed designed in the 70s and also used hand-wound inductors for the resonant circuits, anything more than 5 got way too big and expensive. While the circuit design is Randall / Mesa IP, this schematic and simulation setup (the waveforms attached to this project) were all done by myself. Refer to the site here (Viewed as of Jun 23, 2016): This EQ circuit design was originally developed in the early '70s by Randall Smith, according to Mesa Engineering's web site and a quote by Erik Kirkland of Guitar World. Later on I intend to make a similar EQ circuit that does not use the bulky inductors and is programmable, but will essentially have the same ability to shape tone the way this circuit does. Engineers and producers alike are shocked when they push up the faders and hear how well it goes direct-to-tape.Ĭarry V-Twin with you at all times, as backup insurance or for sit-in situations and always get your tone.Out of respect for Mesa Engineering I'm specifying the second-most restrictive license on this one. In the studio, either V-Twin is a child prodigy. Or can be plugged into any power amp - including the PA. It even has headphone capability that will embarrass the effects-laden digital wanna be's. Two out of three of these dedicated modes are footswitchable, leaving us room to include the Bypass for use with host amps. Though its layout is simple, V-Twin is supremely capable of producing pristine clean sounds and delivering purring blues tones and truly outrageous high-gain rock or metal sounds. With three modes, four stages of all-tube preamp circuitry and dedicated outputs for host amps, power amps and recording consoles, this fortress of a pedal is a fully evolved footswitching preamp. Sired by our Dual Rectifier Head and raised by a Hog-riding armadillo

Mes boogie schematics