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So, following from my NAD thread earlier in the week, http://www.guitarforum.co.za/amps-speakers-and-valves/noad/

I thought it might be interesting to start a project thread to keep track of the restoration.

As I said in the other thread, the amp is in working condition, but does have some issues, and also has had some work done to it that I would like reversed in favour of returning it as close to original spec as possible/practical.

The 4x12 cab I got with the amp has some wonderful 1968 Celestion Greenback speakers in it, but the cab is really ugly, having being painted and recovered rather badly at some stage.

So far, My Program of Work for the project is going to look something like this:

Amp Head

1.) Recover head in original Marshall Levant tolex, including original spec gold piping.
2.) Replace hard wired power cord with kettle style power recepticle.
3.) Replace all pots.
4.) Replace all input jacks with original mono Marshall vintage style ones.
5.) Replace front face plate.

4x12 Cab
1.) Recover Cab with original Marshall Levant tolex, and install original spec gold piping.
2.) Replace grill cloth with original Marshall Salt and Pepper basketweave grill cloth
3.) Rewire cab to 16ohm.

    To start off the project, I've placed an order for tolex, grill cloth, pots and other goodies that I will need. Hope it won't take too long to get here.

    I also decided to explore what would be involved in getting a replacement front panel made. As you can see, the existing one isn't in the best shape, but at some point in its life, someone thought it would be a good idea to make marks on it with a permanent marker, and also a lot of the markings have worn off over time:





    Having chatted to several laser cutting, engraving companies, it sounds like it may be possible to get a new one made, however all of the companies I spoke to require a to-scale design in either some type of CAD or Corel Draw format. With this in mind, I set about removing the existing panel, carefully measuring every aspect of it, looking at other reference pictures to fill in the missing markings and then working in Corel Draw to produce one:
    .

    Anyway, so next week it's off to go and see if I can get this faceplate made. If I'm successful, I'm considering getting the a new rear plate made too.
      Keen to see this, keep the pics flowing.

      As for the front panel, I like the worn beat up look but thats just me. You can probably order a new one from someone like: http://www.ceriatone.com/

      I need a small amount of tolex for a rear amp panel which I need to create as mine didnt come with it. Keep me in mind when you are done please ?
        Yeah I also like the beat up look. The problem is the amp and cab have already been recovered but not very well and not with the proper stuff and I can't live with it as is. So if I am going to recover it then the old panel will just look crap. If it had original tolex, even if it was scratched up I would just leave it as is and then the panel would match.

        Besides I am not getting rid of the original panel so I can easily put it on again.

        Will let you know about tolex. Should have plenty left.
          Stripped head and cab both down to bare wood over the weekend. Eish! Getting the tolex off the cab was a mission! It was well and truly stuck. Eventually made progress by grabbing the tolex with a pair of waterpump pliers and levering it off, inch by inch!

          Filled some dings and chips with some wood filler and then the rain came down so will begin sanding everything down this weekend. Will post pics then.

          *Edited to add: When I removed the speakers for safe storage, it was absolutely amazing to see the amount of dust and debris that had collected in the cone over time. I wouldn't be surprised if 3 of them had in fact never been removed from the cab before.
            7 days later
            After some careful measurements and with the assistance of a local laser engraver, I've managed to resurrect the old faceplate and get all the markings redone.

            From this:




            To this:


            What do you think?


              That's a very good start Shaun. I'm really looking forward to watch the progress made on this project. Good luck hey !
                16 days later
                Looking really great so far, Shaun! Fantastic work! especially on the new front panel! Have you tried the amp at the marked settings? See if the previous owner knew what he was doing or not ?

                (Btw check out JJ "E34L's", a variant on EL34's. More body and very nice. For when the time comes to replace valves ? )
                  Sebastian wrote: Looking really great so far, Shaun! Fantastic work! especially on the new front panel! Have you tried the amp at the marked settings? See if the previous owner knew what he was doing or not ?

                  (Btw check out JJ "E34L's", a variant on EL34's. More body and very nice. For when the time comes to replace valves ? )
                  Hi Seb,

                  The faceplate is still the old, original one. I just cleaned it up and had all the markings reprinted.

                  I haven't tried those settings. I literally got the amp, tried it for an hour or so, and the next day started stripping it for the restore. The amp chassis is with Glen Turrell at the moment getting some work done, but I'll be sure to try them when I have it back and back in the head box. You must come and give it a try sometime when it's back together, probably later this month or in January.

                  Thanks for the tip re the tubes. I'm definitely going to replace the power tubes and have been trying to decide what to put in. If I end up going with new production tubes, I'm pretty sure it will be the EL34L's.
                  Also looking into the preamp tubes and trying to decide whether to replace all/any of them. The amp currently has a NOS Mullard, a NOS Phillips tube, and a Haltron.
                  Just by way of a general update to this thread, this is where I currently am:
                  • Amp head box stripped, sanded, dings filled and recovered
                  • Speaker baffle painted matt black and new Salt and Pepper Backetweave grill cloth installed
                  • Rest of the speaker cabinet stripped and in the process of removing old glue, sanding and filling dings and chips
                  Will attempt to take pics this weekend, if it will just stop raining for 5 seconds! :?
                    Some more pics...

                    Headbox complete:


                    Speaker cabinet stripped and in the process of being sanded and dings filled:


                    Speaker baffle recovered with Marshall Basketweave grill cloth:


                    I'm quite pleased with the way the headbox came out considering this is the first time I've ever worked with tolex.

                    Stretching the basketweave grillcloth over the baffle was an absolute bitch of a job. I managed to get it really nice and tight but it's a job I really wouldn't want to do again.

                    What do you guys think so far?

                      Fantastic ! Few people can really appreciate the amount of work that goes into a project like this. Well done so far.
                        this is looking super cool. hopefully you'll be posting before and afters at the end?! good luck! you're nearly there. also, i might also suggest a cap job if it hasn't already been done recently. a set of spragues and sozo's would probably do wonders.
                          makepeace wrote: this is looking super cool. hopefully you'll be posting before and afters at the end?! good luck! you're nearly there. also, i might also suggest a cap job if it hasn't already been done recently. a set of spragues and sozo's would probably do wonders.
                          Thanks guys. Makepeace, the amp is currently with a tech to have a look at and he did mention possibly recapping especially the big cans. Quite a few of the caps on the turret board seem to have been replaced with square yellow ones, that I think say Phillips on them. I'm clueless on the electronics side so will mention the spragues and sozo's and see what he says. If you click the link in the first post you will see all the "before" shots as well as a pic of the amp guts. Would appreciate any input or advice you guys have for me, so please keep it coming.
                            9 days later
                            Shaun - do not be in too much of a rush to replace those Philips yellow caps - they can certainly be original.
                            They are known as "Chicklets" and do crop up fairly regularly in early 70's marshalls. You should try to keep the amp as original as possible.

                            There have been many strange caps used in Marshalls - here is a pic of my '67 T head with some odd caps - all original

                            If you look closely at those Philips/Mullard ECC83, you will find a code etched into the glass, which can tell you the date and where they were made.
                            The PT has been replaced as well as quite a few pots. Have a look at the OT - should be 784-139 to be original to that amp.
                            I have a bunch of Marshalls from this era, so if you want any info, I can help you out.

                            I suspect this amp was rebuilt many years ago - the chassis appears to be galvanised or something. Not too easy to make out in the pics.
                            The turret board also looks like it is fibreglass, which I think is not correct
                            Buzz

                              Buzz wrote: Shaun - do not be in too much of a rush to replace those Philips yellow caps - they can certainly be original.
                              They are known as "Chicklets" and do crop up fairly regularly in early 70's marshalls. You should try to keep the amp as original as possible.

                              There have been many strange caps used in Marshalls - here is a pic of my '67 T head with some odd caps - all original

                              If you look closely at those Philips/Mullard ECC83, you will find a code etched into the glass, which can tell you the date and where they were made.
                              The PT has been replaced as well as quite a few pots. Have a look at the OT - should be 784-139 to be original to that amp.
                              I have a bunch of Marshalls from this era, so if you want any info, I can help you out.

                              I suspect this amp was rebuilt many years ago - the chassis appears to be galvanised or something. Not too easy to make out in the pics.
                              The turret board also looks like it is fibreglass, which I think is not correct
                              Buzz
                              Hi Buzz,

                              Thanks very much for taking the time to comment, I really appreciate those more knowedgeable than I, commenting and assisting me to learn more about this amp and to restore it.

                              The amp tech that currently has the amp is convinced that those Phillips caps are not original, but has also advised that they are good ones and shouldn't be changed unnecessarily, so they'll probably stay.

                              The chassis has been painted with Hammerite paint. The amp tech who has it seems to think he knows who did the previous work on the amp, and knows him well and will have a chat to him and see if he can get anymore of it's history.

                              The turrent board does look a little different to the pic you posted. I've looked at a lot of turrent boards on the internet and pre '69 boards seem to look like yours, however I've found a bunch of '69 and '70 original JMP's that have boards that look identical in colour and material to mine, so I think the board is original.

                              Look forward to your further input in this thread. I will be adding a couple of pics of the 4x12 cab recovering in progress tonight or tomorrow.

                              I don't have the amp in my possession at the moment, but will check out those valves and the code on the OT when I have it back, but that code you mention sounds familiar and it did have a number stamped on it.
                                I think I remember reading somewhere that the chicklet caps that were originally in '70s Marshalls had the values printed on them, as opposed to later caps of the same type, which had the values impressed into the yellow covering. From your pics it looks like they are impressed, so maybe someone nicked the original mustards along the way. You can see what I mean here

                                  A bit OT, but welcome to the forum Buzz. ? You seem to be an interesting character with similar gear. Mind posting a couple of pics of your gear and an introduction for the rest of us folk?
                                    Thanks Mike
                                    I love old valve amps, and have collected over the past 25 years or so. Mostly old Marshalls, but I also have an old Princeton black face from around '67 as well as a Vox AC50. Most of the amps were in really bad condition, and I have slowly been trying to get them back to as original as possible.
                                    My price and joy is my 1967 JTM45 combo, not really a Bluesbreaker, as it is the first version. The cab had been recovered with something nasty, and i will one day recover it with correct period Tolex if I can find some - it is the Black tolex with the green bits in the depressions. I am just using it as a head at the moment - it is completely original inside, apart from a couple of resistors and a bias cap. (Jim Marshall kindly signed it for me some years ago)

                                    Second is a JTM50 Black flag from '67 or '68, all original except PT has been rewound (badly) I will rewind correctly when I have some time - it is a laborious task.

                                    Third is a JMP50 Tremelo, also 67 or 68 - PT replaced as well, but otherwise all original

                                    No 4 is a JMP50 plexi circa 68, but with replaced OT and PT
                                    No 5 is JMP50 from 69 or 70 with Metal panel ( Much the same as Shauns') I use this as my experimenter - been playing with cascade mods, switchable gain stages and generally fiddling with. I always find I go back to the 67 Bass spec, as that seems to be the best sound for me.

                                    I also have a PA20 from 69 or 70 which is actually the best sounding amp of the lot - unfortunately it does not have quite enough volume clean to gig with. Perfect for recording with tho'.

                                    The little Fender Princeton is actually a lovely little amp - I use it for practises - I have heavily modified it, with and extra gain stage at the expense of the tremelo circuit. I don't get on much with the AC50 - I'll just hang on to it and maybe trade it for something I need one day.

                                    I am always on the lookout for old parts to keep my amps as original as possible, so if anyone has old blown up transformers or anything else, I am always happy to trade (got a bunch of 60'sMullard ECC83)