Was 1976 The Epicenter Of Inconsistency?

[Trapland]

We know Marshall made changes and used whatever parts were on hand many times in their history. It sure seems like 1976 was a banner year for changes and randomness. Why? My favorite amp is a 1976 JMP 4 hole. It's elephant, small logo, gold pipe, new feet, black toggles, no corners. It runs about 360vdc on the plates. I have others I love too, but this one sounds like heaven.

Some things I've seen from 1976 include:
Large logo/small logo
Different feet
Voltage changes
El34 and 6550s even on exports to the same country
Smooth levant, elephant
Random switch types
New models like 2204 with seemingly amp to amp changes
Drake and Partridge trannies.
Piping color
Fawn


What else? I'm curious about that year as the start of new designs, models, aesthetics and discontuation. Plus, does anyone have inside info about staff changes at the factory, etc?

 

[stickyfinger]

Is your model stock el34? Biased at 70% and wall voltage? Ive seem to notice the lower volts models may have only 3 10k droping resistors vs the normal 4 10ks. Lowering to 3 10ks would bring back some voltages to the preamp. Im trying to figure out if this is a good way of looking at guts and being able to assume that model is low volts

 

[Trapland]

I don't remember if it was el34 Or not. I always change 6550s to el34 anyway. If you find the dropping resistor is a real indicator, please tell us here.

And I don't want to bring back the preamp voltages.

 

[Tripel]

Thanks Trapland. Good thread idea.

 

[soundboy57]

76 was a cosmetic transition year to elephant tolex, larger 9" logo on the heads, small check grill (USA) and 11" logo on the cabs, white string for a time, as well as thicker side panels, and plastic corners on the heads.
Many variations during the transition, over many months, from what I have seen and owned.

1975 was the last year of the 6" logo/levant tolex on the heads, and 9" logo/large check grill, and levant tolex on the cabs.

Generally, the above is a rough guide, disregarding any special orders, etc.
There was also some smokey grey check grill cloth that was used for a time in 76-77, that matched
the grills on the USA made "Big M" cabs from 1975. (My first cab back in the day. It sucked and was heavy, but I digress)
My theory is they used up leftover Big M cloth on some of the UK cabs, after the US cabs stopped production (thank god).
I have seen about a half dozen cabs from that period in sale ads, including a friends cab from early '77, with that cloth installed.

By 1977, all the changes were in place, including the removal of the vertical baffle brace in the slant cabs early that year,
I assume to save money.
From many years of observation, the transition heads can be bought for less money than the 75, or 77 era. They don't seem to bring as much due to cosmetics, so keep that in mind when coming across one. All are obviously great heads.
I have never had a bad sounding JMP, from '67 to '79.

My two cents.

 

[Trapland]

My SN is late 5???H.

I didn't get time to open it up, I got sucked into dialing in a nice jazz tone and played big chords on the neck pickup of my Explorer. That darn 76 explorer wants to play anything but rock or metal. Loves country and jazz. It even makes a Marshall sound decent for jazz. Next thing I knew, it was bedtime.

It's been a really long time, but I seem to remember my 76 came with a cascading mod and Master Volume. I don't think it had a changed pot, and I know I didn't take any pots out but I remember tons of gain and a master with volume 1 and 2. There were also some reliability mods done, shielded inputs, screen grid resistors, etc. I restored the original function of a 1987 and left the reliability mods. I wish I would have written down that cascade mod, it sounded good. And if it used the stock parts and no holes, I'd like to try it again.

 

[troyvod]

had a 76 super lead, small logo, elephant tolex, old style box and switches. 76 superbass had new style box with big logo but old style switches..