Trinity Amps has prototyped a 2-tube, single-ended "Tramp" that features a variable DC power supply and a swappable output tube for power stage distortion at a variety of volume levels. Despite the nouveau circuitry, owner Stephen Cohrs tells us not to expect a trendy, all-metal lunchbox for the new amp. The low-power addition to the Trinity line-up, in a hand-crafted pine cabinet, is expected to make its commercial debut by late April.

From his basement workshop in Michigan, MetroAmp owner George Metropoulos tells WJRT television reporter Marc Jacobson that he doesn't need to be in Los Angeles or New York to build amps for big name players like John Mayer. "It's a 21st-century business model all the way. It's Internet based with a lot of networking." Watch the video.

Little Walter Tube Amps is still building octal-based preamps, most notably in the Kelton Swade Vintage Combo, despite a dwindling supply of high-mu triodes in an 8-pin format. "I am buying up all the octals I can find," says chief designer Phil Bradbury. "I sure hope they get back into production soon." Recent 6SC7 inventory at Antique Electronic Supply: zero. We hope tube manufacturers are listening.

Eminence Speaker is launching a new power attenuation technology that varies loudspeaker efficiency at the turn of a dial. Fully cranked the control provides about 10dB attenuation, enabling a guitar player to create 50-watt sounds at a 5-watt volume level.

Return of the rack? 3rd Power has ramped up production of a 2RU rack-mounted guitar amp. The model SV3015 has four EL34 power pentodes split into two independent channels. In contrast to conventional wisdom that players want "bright" and "normal" channels, 3rd Power markets a low-frequency enhancement technology it calls Push.

Vox Amplification says that computer design and visualization software accelerated the time to market for its AC30C2 and AC15C1 models. According to Vox product development manager Dave Clarke, Autodesk Inventor and Showcase software reduces Vox's expenditures on physical prototypes and cuts the company's product development time in half. Boutique amp builders may not share Clarke's enthusiasm for point-and-click design, however, especially at a licensing cost of $6290 per workstation.

Grid 1 launched its Class D battery-powered amp. It uses 1U4 battery tubes for preamp distortion and routes the results to a highly efficient Class D power amp. The amp produces 60 watts for 4 to 6 hours on lithium batteries, very impressive compared to 3S4 pentode power amps. Power efficiency comes at a substantial price premium, however - the amp retails for $3.5k to $4k depending on cabinet options.

According to the Fort Worth Star Telegram, Mouser Electronics has acquired an additional 18.9 acres adjacent to its 432,000-square-foot facility in Texas. We have no information whatsoever that the company is planning a new warehouse dedicated to carbon composition resistors, high-voltage polypropylene capacitors, and other components for guitar amp building, but let's start the rumor here!

Should Peavey Electronics Corporation have been granted a patent for "Methods and Apparatus for Variable Harmonic Distortion?" You be the judge. In his latest post, Pentode Press author Richard Kuehnel explains the technology behind US Patent 7,145,392.

In response to consumer demand, Ampeg's "Heritage" SVT head will be designed and assembled in the USA. The 300-watt stadium blasters are expected to roll off its Woodinville Washington assembly line by the end of this month. Tubes are by JJ (3x12AX7 and 2x12AU7) and Winged C (6x6550).

Budda Amplification will deliver leather-covered guitar amps to retailers by June 2010. The company has teamed with boot designer Mark Nason to adorn 100-watt heads and 4x12 cabinets in fine Italian cow hide.

University of Illinois at Urbana-Champaign is conducting a repeat of its popular Physics of Music Class. Professor Steven Errede continues to push the envelope on vacuum tube amplifiers, guitar pickups, and anything else in the signal chain that can be quantified by a well-equipped lab run by highly motivated students.

Eric Collins at Speedster Amplifiers has re-created Bluesbreaker grill cloth circa 1966 and is offering it cut-to-order to retail customers. Germino Amplification now installs the new grill cloth as a $400 per cabinet option.

Mack Amps has ramped up full production of its Gem heads and combos. The head is only 8 inches wide and 5.5 inches high and weighs in at just 4 pounds. Size and weight reduction are facilitated by an NOS 6AC10 triple triode followed by a single-ended EL84, just two tube sockets to achieve full overdrive that is switchable between 0.4 and 4.0 watts output.

Technical University Berlin released its latest project report on SILVESTRIS, an all-tube mixing board created using advanced design and manufacturing techniques. For those of us living on the unbalanced, 8-ohm side of a circuit board it is interesting to learn about 600-ohm balanced circuits at their finest.

Fargen Amps, which has been producing custom-built guitar amplifiers for more than a decade, has added vintage amp restoration and resale to its business model.

Krank Amplification has re-established its online store to compliment its network of more than 100 dealers nationwide.

Headstrong Amps has signed new dealers in our neighboring metropolis of Portland as well as in Canada and Sweden, where the builder has established its first retailers outside the United States.