This is a glorious 1x12 vintage Australian valve amp that's also a bit of a mystery regarding its brand name, Jason.
Jason guitars were the brand name used to market Japanese-made Ibanez guitars in Australia in the 1950s and 1960s,and it seems that the Jason brand name was around at least in 1958 for a Jason Amplifier and there are mentions of other amps with Jason brand. It also seems Jason may have been the house brand of the music shop Palings in Sydney (I have very fond memories of wandering around Palings on numerous occasions in the 1970s, lusting after the wonderful guitars and amps on display).
The amp has a valve-rectified (6X4) power supply, 2 x 12AX7 pre-amplification and splitter/driver, and two 6EM5 valves in push-pull into a vintage Alnico-magnet speaker. I sounds absolutely killer! I have never come across 6EM5 valves used in a guitar amp before. They are constructed similar to an EL-84 (9-pin miniature beam pentode), but have a slightly higher plate dissipation, at around 10 watts maximum. Assuming this amp isn't designed to screw every last ounce of performance from the valves, you could safely assume the amp is rated around the 15 watt mark. Think of it as a distinctly Aussie-flavoured AC-15®!
A date stamp on the output transformer indicates 1966, while the original MSP 12PQ Alnico speaker has a May 1967 production date, which will pretty-well define the amp's production date - just like this amp's little brother! (click here to see it)
Sonically, this little amp is bloody beautiful! Even with single-coil pickups, it's a surprisingly loud and efficient little amp.
This vintage amp measures 51cm(W) x 42cm(H) x 25cm(D) and weighs in at 12.5kg.
I have been emailed by a Grouse Guitars customer with some interesting information regarding the Jason brand. Here it is in edited form;
Sold to James