The Evolution of Marshall Super Lead

Check out how all changes between 1967 and 1974 affected tone on the Plexi / Metal Panel Superlead amp.
Roe Fremstedal:
The Evolution of the 100W Circuit: From JTMs to JMP Superleadsfolk.ntnu.no/ro...
Clay Finley: Marshall Circuits 101
www.amparchives...

[@dzemohendrix]

Johan, I truly am amazed how in depth you go in your videos. I really admire you, sir. I really do. I wish you any good to come your way. You have no idea how much knowledge you're passing on to us, your followers! I believe I speak for everyone to say: THANK YOU JOHAN!!!!

[@JohanSegeborn]

Thanks, that makes me glad. Have a great weekend! Cheers

[@frederickshawn713]

a tip : you can watch series on KaldroStream. I've been using it for watching a lot of movies lately.

[@jamesjameson5530]

@Frederick Shawn Yup, been using KaldroStream for since december myself :)

[@rombidaut1917]

I come back to this video often, superb lesson Johan

[@Penberth1]

Back to this video again today for more education. I can't remember the exact number of times I've needed to know something 'old Marshall' and the answer has been in a Johan vid, but I'm sure it's nearly ALL OF THEM. Thanks Johan!!

[@JohanSegeborn]

Thanks! Makes my day to hear that!

[@kevinhlavati6285]

You have a vast knowledge of marshall amps. Love your videos

[@100chuckjones]

it's amazing how these amps came along. but its even more amazing how much you know about Marshalls'.. great video J.

[@JohanSegeborn]

Thanks Chuck :-)

[@DIESELPGDOG]

+Johan Segeborn always impressed and more wiser from each video thanks johan for taking the time and effort to enlighten

[@JohanSegeborn]

+paul graham Glad to hear it! Cheers Johan

[@gill2675]

Great video I have a 1974 SLP MKII that belonged to Gary Richrath I bought in Texas, just restored it to stock love it! Roll with the changes, solo was done on that head. I have 6550 tubes

[@timothyn4929]

I am an electronic engineer and I found this really interesting! Not many people know much about tubes anymore.

[@JohanSegeborn]

Thanks man, I’m glad to hear that!

[@timothyn4929]

Johan Segeborn I built a 50W JMP and was thinking it sounded too thin. I used this and your video about the Model 1986 to decide I should do some mods. I converted it from the 1987 type spec to the 1986 and I love the fuller sound.

[@jaaprince]

your channel is an Audio/Visual Encyclopedia of Marshall Amplifiers (and other historically relevent guitar amps). An invaluable resource.

[@JohanSegeborn]

+John Prince Thanks John, it's so good to hear that!

[@JoeGuitar]

Amazing breakdown !! This is the "definitive" breakdown of Marshall 100 watt amps. Thank you for posting this Johan. This is a wonderful resource for all posterity.

[@JohanSegeborn]

+Joe Strabley Thanks Joe! Really glad you liked it. Cheers Johan

[@nathanburns8021]

Johan I love your videos. I really want my own plexi head some day and watching your videos tides me over until I can afford my own. Theyre so expensive but you make them seem insanely worth it. Cheers!

[@JohanSegeborn]

Thanks Nathan, I'm really glad to hear that!

[@sylvainbebert3704]

Thank Johan for all these great jobs you done ! For those interested in cathode resistor, they introduced the 2K7 value of V1b (1:18") to shape the low frequency fall-off in input, very important feature for that tchonk on palm-mute. Yes most pickups do have too much bass for proper distortion, this 2.7 value is the solution, really makes the difference as soon as the crunch and the associate compression comes, it sets the ideal amplitude balance between upper boosted, and lower almost non-distorted giving that playability Marshall are known for. Every and each amp in the world now uses this value in the boost channel, and now thanks Johan again I know what year it cames on, and it's 69 ! That's the year I come also, wonderful year !

[@JohanSegeborn]

Thanks man, glad to hear it!

[@judeconig9324]

Thank you so much. I've just finish a Point to Point PLEXI and this is excellent.

[@DANTHETUBEMAN]

engineering a sound , there are so many ways to get there in a amp, when i herd you play the plexy 50 Watt 1987X, it was all there, and that is all modern caps and resistors, so it can be done. the variety in the old amp runs and tube runs was and often is quite a lot, a jazz guy may find a clean marshal and love it, right after playing a dirty sounding one with more early brake up that the blues rockers swears by. its a interesting thing we do try to express out selves through electronics

[@JohanSegeborn]

Yeah indeed, well put

[@lennyluzitano8920]

JOHAN YOU ARE AWESOME ...THANKS....

[@soapboxearth2]

This is so helpful for the build inhale coming up next. Doing a 68 1987 . But it's great to be able to reference the differences. I'm thinking about adding an nfb switch or maybe pot

[@Mister_Greg]

Thanks Johan. I’ve been tweaking the preamp in my Vintage Modern and your information has been extremely helpful. Love all the work you’ve put into your videos. You know your shit.

[@incubism]

Wow, that was epic. I am going to take my plexi home from the rehearsal room and examine the board again. Thanks Johan!

[@JohanSegeborn]

Thanks!

[@manawarrior2010]

You know more about my amplifier than I do. Subscribed. Many thanks.

[@JohanSegeborn]

Thanks Gareth

[@Auxend]

Johan, from your first utterance of the word "Hi" to every single video since, you have constantly inspired me to stay with what I love by intuition and science and thoroughly geek out on it for the pure joy of it. Thank you, I'm glad you are on the same planet as the rest of us.

[@davemcafeeguitar]

Excellent analysis, been looking for a comparison of all the specs. Thank you so much for posting and sharing this!! 🙏

[@PoJoWo]

Such a well designed video Johan your approach to highlighting the table really gives the data some focus with what you're saying. You'd make a great lecturer in engineering. I have an old 2203 that I got and someone had rebuilt it as a super bass with tag board. I made it back to plexi specs as used it as a test bed for mods for years. I once set up a switch on the back to swap between the extremes of the nfb 27k on the 16 and a 100 on the 4 ohm. Such a hugely influential element I'd not realised till then. The lesser amount of feedback made the cab so much more influential in the tone, but so much louder. Given that this made the amp louder sooner I found that the bright cap would suck more low end at gigging volume. I know I could have rendered that moot if I'd got into attenuators but it certainly told alot about how the later amps must have been in common gigging use and got me thinking more about influence of stages of eq than I would have otherwise. People must have had a real shock getting a newer Mk2 in the seventies after having a plexi. No wonder there are so many tales of the players saying they couldn't find amps to replace older ones. And when you think of the simplicity and low price of the significant few components it's amazing to think how close they were. That's why I started blueprinting mine before selling in trying to catch the magic lol

[@PoJoWo]

Sorry for waffling on!

[@JohanSegeborn]

Hi my friend, I always appreciate your feedback, so the longer the better :-) I've held a couple of engineering lectures in my day actually :-) at Chalmers University of Technology in Gothenburg. Cheers

[@igorsuv]

would be nice to see the same video about jmp/jcm. especially to show to us why later jcm800s sound thinner (horizontal inputs, etc)

[@pho2]

This makes for compulsive viewing. My 1971 Purple 100w super bass is being over hauled. I have not played it for 27 years. In fact i have not had the opportunity to play it cranked since 1978. I never forgot that incredible sound and energy, I want it back now.

[@reneotten7376]

Do you have it back and are you enjoying it?

[@johnmarshall3903]

Hope its sounding great.

[@diegofernandezregueiro5814]

great lesson of history my friend

[@JohanSegeborn]

+Diego Fernandez Regueiro thanks my friend! Cheers

[@HofiAgilAghov]

Beautiful video Johan. Each year of these vintages, sounds different and unique. Its great to see the correlation between musical needs of the era and the amplification manufacturing responding to that, striving for more gain and more highs each time. In my opinion they all sound better with KT88’s. The EL34 sound classic but just somewhat standard. Cheers!

[@cornraft]

Absolutely amazing Demos as usual !!! Awesome info on these early Marshall's !!!

[@JohanSegeborn]

Thanks, glad you like it :-) Cheers!

[@nighttrain022]

Priceless, incredible, Invaluable video. Thank you, Johan

[@TheStrangebone]

Dude thank you so very much for taking the time for such an informative presentation. For many years I had based the year model of my SL on the serial number alone and everyone I spoke to agreed it is a '69/'70, but based on the 100k NF resistor, the C2542 choke and the C2668 OT I now believe I hold a 1971

[@hrsey71]

well, this answered so many questions i had about tweaking the components in my amp.. amazing video!

[@angusmcflynn]

Love it Johan. Please do more of these videos! Thank you.

[@brentstewart59]

This is gold right here Johan Thank you

[@brianlycliter]

God bless you brother..... love the fact that you have taken the time out of you life and to make Marshall amps a large part of your life .... im currently using Marshall 2466 1/2 stack and bogner Shiva 6L6 combo ... hoping you can answer question about v4. of the vintage modern and recommendations of a tube PI.

[@shakeyjonez]

Thank you for this. Now I have the basis I need to mod my Ceriatone Plexi to get what I want out of it.

[@pauloacedo7461]

Nice .I read somewhere a long time ago that Hendrix had his heads running on 6550 in US and EL34 in Europe .This explains the more open and not so distorted natural sound in Woodstock ,Filmore East and so on during some 1970 gigs compared to the early gigs in 67/68 a much more harsh and distorted sound .This was stated by one of Jimi´s amp techs .This guy also revealed that Hendrix favorite heads were those with the higher +B voltage up to 480+ volts ,he had personally checked that ... But the video chart shows 6550 only from 1971 and up ... anyway ,very good info there

[@roncarter2188]

Great video and great job of breaking this all down as to what is laying down the distinct Marshall tone of the early years and the later years, these specifications on these components is what I resort to when I tweak my amplifiers and modify them it's between these specs for Fender and Marshall. Fender has the great clean tone and Marshall has the awesome overdriven sound. And then you have all the great variations of both.

[@krauz111]

you my friend are a Historian !

[@JohanSegeborn]

Thanks Carlos! :-)

[@bluevd12]

In 1968 i bought my first marshall 100 watt. Super bass is the only one i could find on the shelf. It stopped working on my first gig with it . Took it to merson in westberry ny abd kenny frank attended to my amp personally and found two filter cap unsoldered laying on the bottom. As he resoldered everything he asked if i would sell the amp to him for Jimi because its transformers put out a larger amount of current . I said no id really like to keep it . He said then let me set it up like Jimi and he did a few things like changed out the cathode caps and the main thing he did was change the cap on the volume pot to a 1 i think it was. This made the amp come on straight away at about 3 . It was outragious ..as i found out later as i knew nothing about amps in those days that jimi kept his amps full on which would really defeat the initial caps action . Who knows i knew that amp was outta control after what he did .. anybody know anything more ??

[@jprg1966]

I've wanted someone to do a video demo of something like this. Thank you, Johan!

[@JohanSegeborn]

Thanks!

[@davebird534]

Hey Johann you are a national treasure to your country in the United States as well as the uk! I learned a hell of a lot! I had many bassman and vox ac30s back in the day. And while I was pretty darn happy with my tone I still wanted to get that really good vintage Marshall tone that I've heard before it records but I just didn't know what exact model amp and what year was used. And now I know ! Those older transformers and the 67 jtm45 and jtm Black flag cancel magic in him the change in that particular camp you talked about 68 camp in 1968 started to dig maybe it had more gain but it wasn't a good smooth and detailed kind of gain. Can you pointed out the pinstripe grill cloth was use in 1967 to the basket-weave. You said depends for a girl called had a positive effect of removing a lot of the harsh iron frequencies. I suspect that probably helped the 67 is well sound better. Although you did not say whether or not the basket we was any better or worse than the pinstripe grill cloth. But you did say the checkerboard was not very good because it little out of the high-end ha frequency through. I believe you said maybe it was 69 or 71 or something like that. So the the earlier late 60s celestion speakers would have had a slightly smaller ceramic magnet could have affected the tone and most likely in a positive way. I've experimented with Alana speaker magnets Jensen's celestion and I sometimes found a slightly smaller magnet ceramic magnet of medium size not too big or not too small, oftentimes can sound better. They're a little bit looser and liquid sounding but not overly so. And they can had a really nice smooth grind when they breakup ad to saturate the overdrive quality and amount. . and like you pointed out and send me your earlier videos where you proved and demonstrated that one 12-in speaker bigger and warmer sounding than a 4-12 marshall cabinet !!! That absolutely blew me away when I heard holyshit standing waves frequentcies in the speakers cabinet were cancel themselves out input each other and weird nasal out of phase sound.

[@kirkgreenman1386]

Johan, That was an Amazing video. Thank You.😊

[@TwoSheds160]

This is fantastic stuff! Thank you so much for all the work you put into these videos!

[@JohanSegeborn]

+Daniel Culley Thanks Daniel! Glad to hear it :-)

[@atbear]

This was great. Great explanation and visualization of a topic I'm currently researching. Thanks!

[@JohanSegeborn]

Thanks! Check this one out too: kzbin.info/www/bejne/Z2GQmHyihtdsntE

[@erickrada0]

i feel i owe yo so much. Your explanations are simple but really understandable. I'm bout to build an amp and wanted to inform myself of this kinds of things. Thank you so much, johan.

[@wammbarro]

Great video...as always, Johan. Keep it up. Many thanks!

[@JohanSegeborn]

+wammbarro Thanks! It'll be my pleasure, Cheers

[@brianbuckner2768]

Hi Johan, I myself have a pretty good knowledge about amp circuits and you're done a fantastic job on this video and made it very easy to understand. You have the knowledge, why don't you try to build a circuit of your own? That's how Dave Friedman started, he just loved Marshall amps. Anyways Bravo sir, great job and thank you for being one of the best channels on KZbin!

[@JohanSegeborn]

+Brian Buckner Thanks Brian, glad to hear that. Cheers Johan

[@xorbster]

tjena, vore grymt kul att se en liknande video för super bass! cheers.

[@JohanSegeborn]

Tjena! Det kan jag fixa. Superbass kretsen ändrades mindre än SuperLead.

[@aijb]

Love your videos Johan! Wondering if you'd be able to do a similar video on the evolution from 1976-1981? Thanks!

[@JohanSegeborn]

Hi! Glad to hear it! That would be my pleasure, consider it done! Cheers Johan

[@aijb]

YES! Lookin' forward to it :D

[@alejandrogabasabarcoj8658]

@@JohanSegeborn Yes please, it would be very interesting

[@rts4133]

I love all Marshall amps. I took my old 1980's Marshall Lead 12 practice amp and I drilled a hole in the back and put an output jack , and I use it as a head. I run an Ibanez Tube Screamer through the gain channel. Gives me the exact sound I'm looking for . But one of my favorite mods of a Marshall amp is the "Bradshaw Dookie mod" . The singer and guitarist from Green day had Don Bradshaw his amp tech modify his old Marshall plexi head. He modded it by adding a master volume and beefed up the gain curcuit. So , you get the classic plexi tone but with a super cranked gain . The sound is very similar to taking a Variax and pushing the power to the limit. So basically it gives you the exact same classic plexi tone but the gain curcuit pushed to the limit.

[@Bat21bravo]

Great job, well played sir !

[@gustavojazz4514]

Amazing vídeo, great work!!!!

[@BlackBalloonGraz]

Great video Johan. Thanks alot.

[@harleybrujo]

Well done Johan! Cheers from Merida Yucatan México

[@JohanSegeborn]

Thanks Harley, Cheers!

[@Eywadude]

That was a very good video with some excellent information. Thank you very much for making it. Bookmarked. :)

[@JohanSegeborn]

Thanks! :-)

[@FreddyFuFu]

Holy fucking shit! People analyze the effects of grill cloth on the sound! I never took that into consideration when I chose a grillcloth for my custom cab. I just went for the most pleasing visual effect.

[@bradt.3555]

Very cool, I don't think people realize just how many changes Marshall made over the years. That's why I find it kind of funny when people use generic terms like the tone of a super lead. It's like which one? Though all Marshalls have a distinct tone. I have to admit I am a Soldano nut, but still love the " Marshall " tone. I've got an old Elk 30w amp from the late 60's given to me dead. Had holes melted in the OT tube plates. So many caps later it runs great. Lately I've kinda been Marshall obsessed so I did some revoicing on it and made it kind of a cross between a super lead and super bass, but only 30 watts. Sounds pretty cool. It uses 7189 OT tubes which are a higher rated el84. B+ is 420v as opposed to around 325 for 84's. Enough of my rambling, like your vids when I want to hear different Marshalls.

[@JohanSegeborn]

+Brad Tomlin Thanks man, glad to hear that!

[@vadlasletta]

Love this! You should do a collab video with fenderguru from norway! Now we need same kind of video about the super bass!

[@chivato666]

Great information tremendous, congratulations. You could make a video of how the capacitor fuses affect the current input of the amplifier, and also the difference when using parallel capacitors in the diode bridge in the ac /dc rectifier.

[@inlasttonowhere4459]

Thank you good sir for you wonderful and enlightening videos :^)

[@davebird534]

Oh yeah and it one guy mentioned tubes of course that will make a huge difference as well as the speakers do. I can tell you as a vintage tube seller on eBay and being a guitar player in fellow tone chaser you can't do much better than mullard ecc83. However I find that I like to mix the muilards with either telefunken ecc 83 or good ole' long black plate square Getter RCA 12a x 7. Even the long gray plates and pretty good to from1959. What's the Telefunken does is it smooths out the crunchy bite. The Millers had an excellent overdrive quality to them and they actually pump up the mid-range and they got good strong bottom end, and a round topend. Donnelly do they do that but they extend the high in frequency in the extend the the low end frequencys. Causing the sound the sound bigger and more open. Almost 3 d like. RCA's don't have quite the top 10 in the bottom in the extension but they have a really nice rich colorful in the mid mid range. Are just a lot more smooth and detailed on my vox ac30 generally I will run a mo Mullard in V1 a Telefunken long smooth plate in v2. Canyon V3 on my vox ac30 hand-wired that happens to be the phase inverter. Honestly I don't want to run to Hot n crunchy have a team there because it would detract from my detail and clarity. That's why I run the RCA long black there. Of course in the vintage 60s voxes you had an extra tube or two 12ax7. In that case i would us two molars one in v/1and another balanced mullard in v/2. . The older mullards with a long plate square getter mc1 from the late50s are supposed to be the best best. Honestly most all of them up to revision 165 blackburn England sound pretty damn good. As long as you're using balanced pairs together. The revision 161 and 165 from the years between 1961 and 1965 where the round Halo get her short plate version. Didn't even need still had a lot of power and strong mid range forward sound. . I sold these to Rich Robinson and Chris Robertson's guitar Lindsay of The Black crowes. Lindsey told me that rich likes those better live because you're not nearly as microphonic on stage yet still sound strong and good. Those guys also like amprex 12ax7s.red label for hammond in the early to mid 60s. Rich likes mullards el84 particularly 1959 square getter. Chris usually uses a marshal 50-watt jmp and he likes the mullard el34 double o getters on the bottom of the tube. Brown base.

[@alexfarmer9051]

priceless info, thank you sir! love your work

[@Jose-li2uw]

Thanks Johan!great video!!

[@JohanSegeborn]

Thanks Jose, glad you liked it!

[@danagboyer]

Excellent video, Johan!

[@JohanSegeborn]

+Dana Thursday Thanks Dana!

[@etronnel]

VERY precious information thanks for this video

[@JohanSegeborn]

+steeve thomas Thanks Steeve, that's great to hear!

[@ainsleystones4600]

Fantastisk Johan! Oi Oi! I have what is apparently a late '67/early '68 Super Lead, which apparently is identifiable as such because of the power board...or something! Jeez, I'll stick to playing through it! 😅

[@mariosavard2863]

Thank you !

[@bradt.3555]

One thing that would be cool is take a couple of the different 4 input amps and compare the hi-lo, dark- bright of each. Thanks for the great videos.

[@roncarter2188]

Beautiful breakdown of these amplifiers, can I download or can I get a copy of the chart you are referring to in this video? Thanks so much, keep up the good work.

[@pablorey7392]

thank you very much for your work and contribution. Would you comment sometimes on vivid examples of Marshall tone on certain classic tracks? your licks sound classic and your use of bar chords sounds like a good use of Marshall tone. Thanks again.

[@JohanSegeborn]

+pablo rey Thanks Pablo! I like the Matshall tone on 1975 Kiss Alive! Which are likely 1973 SuperLeads, The Van Halen track Unchained. Jimmy Pages live tone, to name a few. Cheers

[@pablorey7392]

Thank you for your help with my education on classic rock!

[@brandonhupp464]

Johan your English is so fun to listen to!!.. I sound too much like John Wayne happy Friday brother your reviews are always keep rockin!!! :)

[@JohanSegeborn]

Thanks my friend :-) but you can't sound too much like John Wayne, he has the coolest speaking voice ever!

[@BlakeC27]

Great information my friend!

[@JohanSegeborn]

+Blake Coster Thanks, Have a great weekend my friend!

[@BlakeC27]

+Johan Segeborn I forgot to ask; any information on the changes in value of the bright cap across the volume pot of the High Treble channel across the years?

[@JohanSegeborn]

+Blake Coster that one was constant throughout the Super Lead years. Earlier (JTM45/100) it was smaller or not there. Cheers

[@BlakeC27]

+Johan Segeborn 5000pf?

[@JohanSegeborn]

+Blake Coster yeah, it was 5000 pf for Superlead, but may´be 100pf before, but I'm not sure. Cheers

[@michaelbousquet2362]

A great lecture on timeless amps! Question, are those same changes present throughout the evolution of the 50 watt models?

[@JohanSegeborn]

Thanks Michael, thats an interesting question, many of these changes are applicable on the 50 W Lead too, but not all. They had different suppliers of transformers for instance. I'd be glad to do a 50W clip too! Cheers Johan

[@uwetittmann1423]

This is incredible, what an extensive work! Unbelievable and many thanks to you, Johan. However: I had an 1967 original 100 Watt amp at home and the incredible thing was: I had an almost infinitive "standing" tone on my old Fender Stratocaster with it at moderate loudness. How can this be? No modern amp, except maybe my Hughes & Kettner Black Spirit 200 can do this?

[@johnnyz3532]

Is the year vs. component table shown in the video available for download? Amazing information.

[@scottdunn2178]

Man, I would love to have heard Ken Fischer's input on this.

[@kenjohnson6368]

Johan, like others I watch tons of your videos as it truly adds to the "book learning" we get from the books on Marshall. I now know I need to find a Dagnall C2668 for a 71 SL with a replaced OT ! On another note I have a pair of 1979 checkerboard cabs with g12h blackbacks and wanted your advice on the ideal head to get the most from those cabinets sound wise? 2203? 1959? Would love to stay I the 78-80 year range wise. Thanks

[@JohanSegeborn]

Hi Ken, glad to hear it. I would check out a 77-80 Super Bass with those speakers

[@doggorman]

Im not sure if u mentioned this but in 1971 some superleads still had Drake transformers. Also these transformers had diffeent numbers on then then the usual Drake and Dagnall transformers Ive only seen this with 1971 Marshall superleads(custom colour) Ive seem this documented on the forums with owners of 1971 Superleads including my 1971 superlead. Im not sure but the current "Mike DoyleMarshall book" has photos of this showing various custom coulour Marshall superleads of the early seventies? Id like to say also that of coatse all these Marshall amps sound great but I especially have good luck when plugging into a 1971 Marshall superlead(not to agressive and just right) Thats my experience!

[@jefferyaeastman]

Don't forget about a small amount of the early 70's models got the C2373 Dagnall. Rare enough that nobody can tell me the specs for it across the primaries!

[@danwguitar8651]

Awesome video Johann! I can't believe I have only just found this considering how long I've been watching your videos. I have always wondered about what changes have been made through the years to make them sound so different. Do you know what year Superleads Jimmy Page and Angus Young used? And do you know if Angus' were modded? It seems like there is a lot of gain in his signal in particular.

[@TheOldgitarist]

you know your stuff

[@peterschaefer1665]

Thanks again for another very valuable informative video. So it sounds like the early '68 circuit was the one to have?😉

[@blop1738]

What a video! Hi Johan. I'ld like to know if there's any circuit difference (cathode resistors, caps, tone stack or anything else) between the ''65-66 JTM45/100 and the '67 JTM100. Thanks

[@fredyvh1]

Hello Johan !Do you really find differences between Drakes and Dagnalls transformers ?, I suppose it is a difficult question but I would like to know which are yours experiences ....cheers from Spain !!!!

[@andrewanderson3746]

You're videos have been really interesting and useful, thanks man! have you ever done a comparison of a variety of humbuckers? I'm currently trying to find the right one for me.

[@andrewanderson3746]

although i should probably specify that it is output levels of different humbuckers that id like to compare

[@JohanSegeborn]

Thanks Drew, I'm comparing a high output to a low output humbucker in this clip: kzbin.info/www/bejne/fqTcnWusqLmtfLc

[@LPCustom3]

Johan; Hi! Even though you did this a couple years ago, it would be fantastic if you did a similar video for the 50 watt heads as well. Cheers mate!

[@JohanSegeborn]

That’s a great idea. I will! Cheers

[@lennyluzitano8920]

Johan Segeborn the master speaks... So listen and learn....good buddy thanks....

[@phildemetro]

Another great video! Johan, do you have any mods done to your late 70's JMP? Disconnected bright cap, etc...?

[@JohanSegeborn]

Thanks Phil, I havent done any mods myself, and I think they're pretty according to spec. Cheers Johan

[@WW-jz8zd]

Thanks for doing this. Such great information in there. Is it possible to download this chart from somewhere?

[@Smartmax79]

Hi Johan, I like your Videos and many thanks for the enormous Information we get from you :) Great work. Do you also compare cables ? Like a VoVox against normal cheaper one ?

[@qua7771]

Odd that some had a V2 cathode cap, and some didn't. Spec's shows a cap was used, but I don't see one on many of the amps I've seen.

[@piamp4012]

Thanks a lot ! great vid ! Do you know how the B+ evolved too ?

[@danielborotto299]

Hi! Very clear explanation, thanks! How the change of the choke transformer in 1971 influences the tone compared to 1969 specifications? Thanks!

[@Dateninkontinenz]

Hi Johan, do you know if the same changes where applied to the 50 W lead model over the years? Or was it unaltered?

[@JohanSegeborn]

+Dateninkontinenz No most of these changes were applied to the 50W too

[@Bourbon-Canted-Ky-Windage]

Excellent as always!! On the G12H30s, which years had 55hz cones and 75hz cones?

[@JohanSegeborn]

Thanks Danny, Marshall actually only used the 55Hz (T1281) version. I think those existed between 66-80. The 75Hz version (T1217) were used by orange and Laney for instance. I’m not sure if they also were introduced in the mid sixties or if they came a bit later. The earliest I have are from 71. Cheers

[@alejandrogabasabarcoj8658]

Hi Johan! Thank you for these videos!. I would like to ask you about the 90's and current super lead reissues. What is the exact era reissue of the 1987x and SLP? 1968 PLEXI? 1971 metal panel? 1974-1976 mkII? And the 1959 HW? Which transformers use these current models? Thank you!

[@rocker8692]

I wish youd check out the Friedman runt 50 circuit, hows its different then a Marshall, cause I really like the runt 50.

[@emergencynurse02]

Nice Survey ! exactly what I needed....How do I get that awesome chart, that would be Very helpful in my "tonequest" are you preparing a survey for the 50 watters or are they pretty much the same ....?

[@JohanSegeborn]

Thanks, they are similar but there are differences. I'm gonna do a 50W version soon. Cheers Johan

[@zakmichael]

You should do a video about the transformers and the difference. The Heyboer and the Drakes specifically.

[@JohanSegeborn]

+zakmichael Yeah, the Output transformer is the amp basically

[@tweedguitar9103]

Dear John, Would the data on the '67 Super Lead model be the same, and applicable to the 1967 JTM50 Black Flag with Solid State rectifier, and the 1967 JMP 50 with Solid State rectifier, in relation to component values listed ? thank you for your valued assistance. TG

[@JohanSegeborn]

+tweed guitar much of it yes

[@ak01q]

Johan, FYI the Clay Finley: Marshall Circuits 101 link doesn't work.

[@rastan17]

Is it the same specs for 50W amps?