Amp seem the Scandinavian model. Appears to be a 1987 50 watt model with 4 inputs. Headshell is not original to the amp as only 100 watt JMP's had vent on top. 79 is first year for JMP serial on front so good possibility its a 79. Canada & Scandinavia models have no 16 ohm speaker tap so limited there. Also these two export models have internal mounted fuse boards. Daly filter cans seem original. Likely time for new ones if going to be gigging, replace the bias caps as well.
Ok so the mystery continues Probably a canadian/scandinavian export non-master, 4 input, 50 watt 1987, installed in a 100watt head box ending up in sweden in the early 80's. Very nice. I will check the drill holes when i get back home. Any other suggestions? Fellow Swede Wenander has posted a picture of his 50w 1987 export with the same backpanel as mine in this thread, 6 posts down. https://www.marshallforum.com/threa...questions-if-you-have-one-please-read.114245/ So the problem now is the volume since i live in a small flat in a building from 1905... Any tips on attenuators? this is the setup now. The ibanez bp10 compressor was also included...
No mystery. Its a "built for Sweden" amp. You can tell by the "S" sticker. It's the approval of "Semko" swedish equivalent of UL in USA or SCA in Canada. The heat breaker between the output tubes was a Sweden only thing, I believe, that appeared a few years in the seventies. It will have fuses for everything, almost, on a separate board on the inside. Similar to Canadian Market amps. Probably sounds great after some tlc. J
The 100w cab is interesting. Might it have been a combo? As for attenuation, it depends on the ohmage of the cab. If it’s 8 ohms, I would always recommend a Marshall Power Brake.
Hehe I still want it but maybe someone who can actually play on more than 0.5 volume has better use for it so might have to sell it unfortunately.
If there is metal shielding on the bottom of the headshell beyond the 50 watt chassis which there should be for a 100 watt you have your answer. Hard to tell in the pics but i thought i saw it. Im positive about the vent on top for 100 watt only.
Check out these videos from Euge Valovrita. It's a great review of what I believe you're trying to achieve: BUGERA PS1 Power Soak vs SUHR Reactive Load / I.R. - Direct Recording - YouTube BUGERA PS1 POWER SOAK - Crank your tube amp and play at bedroom levels. - YouTube
No extra shielding, no extra drill holes either - looks factory made. I guess the 100W amp is wider and there would be some signs of a change from a 50 to a 100w during the years.
Congrats. Great amp! Michael Shenker's favorite for lead work . . . and you can't argue with his tone!!
Nice amp. Beats the $900 I paid for a '73 1987 and 70's cab a few years ago (non-original greenbacks though.)