The very first Mark I was made in 1969, when Smith, as a joke, modified Barry Melton's (Country Joe and the Fish) Fender Princeton amplifier. He removed the standard 10 inch speaker and modified the chassis to fit the larger transformers that were needed by the 4-10 tweed Fender Bassman, the circuit that he had added into the 12 watt Princeton. Finally, mounting a 12 inch JBL D-120, a popular speaker of the time, Smith had created what would be the first Boogie. Randall Smith took the "hot-rodded" Princeton into the front store. Coincidentally, Carlos Santana was present and "wailed through that little amp until people were blocking the sidewalk." Impressed, Santana told Smith, "Man, that little amp really boogies!", thus providing the current name for the amplifier and the company.[1] "Mark I" is the moniker given to the first Boogies ever made, although they were not called "Mark I" until the Mark II came along. They were 100 or 60 watts combo amps with a 12-inch speaker, primarily Altec-Lansing 417-8H Series II. The Mark I had two channels: one clean (voiced somewhat similar to the original Fender) called "Input 2," and one "high gain," called "Input 1," which produced the overdriven "Boogie lead" sound used most notably by Carlos Santana on the "Abraxas" album, and after by The Rolling Stones, with Keith Richards and Ron Wood using the amps live from 1977 until 1993 and in the studio on classic albums as Some Girls and Tattoo You. This amp in its original form is very collectable, but does not have footswitching capabilities--one plugs into one or the other input for the two tones. Reverb was optional, and not present on many early Boogies. Later, Mark I models were available with reverb and/or graphic EQ. Early models have "slave out" and "reverb" labeled on the back with Dymo stick; they do not have any "pull lead" capabilities on the volume controls. Later models had "Pull Bright" and "Pull Boost" on the volume controls. The front panel controls were Volume 1, Volume 2, Treble, Middle, Bass, and Master. These early models are fairly inconsistent, since many of them were "custom" models, made-to-order for various buyers. Mesa/Boogie has stated the original and the reissue have a "looser" lead sound since the first two preamp stages occurs before the tone controls. In the various later Mark II and III models, there is only one gain stage before the tone controls. This signal chain is an issue of some dispute among Boogie owners.[citation needed] [edit] S.O.B. (Son of Boogie) The S.O.B. was introduced sometime during the Mark II era. This was Mesa/Boogie's first attempt at having a "reissue" of the Mark I. It had 2 inputs and its controls were Volume 1, Volume 2, Master, High, Middle, Low, Limit. The "Limit" seems to give distortion to the amp while maintaining the volume. This amp is highly collectable...There a NO NICKS, SCRATCHS,DINGS, DENTS!!! It is in MINT condition!!!!see if you can find one on ebay!!!! there is a mark II which came after the sob for over two grand!!! Call me now before it goes for bid on ebay. 443-825-0239 Location: BALTIMORE it's NOT ok to contact this poster with services or other commercial interests maryland