"While on Weezer's Northern California tour in August '92, Rivers bought a curious Mesa/Boogie amplifier (pictured inside the Blue album cover on the left side) at the Berkeley Guitar Center. I have never ever seen an amp exactly like this one since. It was a very early issue Mesa/Boogie, from approximately 1977 or 1978, and its face plate said "Mesa Engineering", which predates the addition of "Boogie" to Mesa/Boogie's name. It was a 60-watt head which apparently didn't even have a model number (I remember looking for one several times). It sounded incredible, and its real bonus was still sounding rich and thick even at low volume, making it ideal for recording demos late at night in the Garage. Sadly, while on tour in '96 (by this time as a backup amp), the Boogie suffered a near fatal blow from an unknown source during shipping. At some point during the tour, the amp was fired up to check it, and it sounded terrible. It was supposed to have been taken in for repairs, but apparently was lost somewhere, either at Weezer's storage facility in Los Angeles or later, when Rivers was living in Boston. No one seems to remember where they saw it last, and it is gone. Several fans have written in with info on this amp, but most identify it from the reissues. I have checked the reissues but none are exactly the same. However, several people wrote in with the explanation that this was the 60-watt version of the Mark I head. The reason that the amp had no name on it is that it was not named until Mesa/Boogie issued their next amp, the Mark II. A reissue version of the Mark I is available right now from Mesa/Boogie in a 100 watt head or combo form with a switch to reduce the power to 60 watts, and it is that edition that some people were confusing the "vintage" amp with. Patrick Wilson today owns a Mark I reissue in fact, and can confirm that the old one had some pull out knobs that produced amazing sounds that the current reissues do not produce. It's entirely possible that the pull-out knobs were a custom job..." - Karl Koch, weezer.commore
This 60W mini head has a push-pull high gain stage that really gives you the 70's distortion you're looking for. Each amp was made-to-order, and in this case you can get them in combo or heads. Rare as hen's teeth, mine has an international voltage selector along with reverb and an fx in/out. This is one serious amp!