How to install Master Volume Marshall Super Lead Plexi easy method without removing circuit board

[@analogblues9606]

Thanks Terry! Between this video and Triode diagrams your demonstration made it easy to do on my 1972 50 watt Marshall! 👍

[@joeyvanostrand3655]

That is such a beautiful amp! The circuit board is so clean, so perfect!

[@doofwop]

It's a reissue, not a real vintage piece. PCB has tiny modern components on it. A real vintage amp would have turrets, or at least much much larger PCB components. Because caps & resistors were much larger back in the day.

[@SeanRomin]

Hello! I just want you to know that I’m absolutely enjoying your channel and aim to learn everything you are teaching. I consider it a huge privilege to get to learn from you. In this video you mentioned you would send documentation for this mod and would be very interested in getting the documentation for this. Cheers!

[@dennisflock3958]

Always great amp repair. Happy Wednesday from extra Windy Chicago.

[@1thess523]

I really enjoy story time and just your normal humor it really makes the technical stuff for a non technical person like me watchable 😀👌. If you lived in my city i would supply you with juice from the vine 🍇🍷because i work for a wine distributor 👍. As a matter of fact I have 4 case's of wine I need to give away 😁.

[@sski]

Nice clean mod for a beautiful amp. Thanks for the walk-through, Terry.

[@halbertking2683]

Leave the 220 k bias feed resistors on the board. Install a dual 1 meg pot linear pot . Wire each half of the pot across each 220 k . 1 dual pot , 2 wires , 1 knob. Least invasive .

[@JohnHorvath73]

What's the name of this type of master volume?

[@monto39]

Pretty nice, seamless job - the placement, knob choice and lettering look like it was done at the factory. I kinda like the PCB layout Marshall used also. It's still got a layout like it'd be on a Turret Board, just no wires or visible leads.

[@kenhancock8931]

THX TERRY .hope you marsha & shortwave girl :) are having a great day!!!

[@Finom1]

Brilliant Terry. Thank for this educational and informative video. We love love it, your the best.

[@rciancia]

Clean neat and clear job Terry !!!!! You showed them Brits how to do it :)

[@GL64]

Good vid. Having done quite a few of these myself, it might be helpful for some people to pre-wire the pot before you make the board and tube socket connections.

[@d-labelectronics]

I agree

[@Tboyhoot777]

amen ... that can really slow slow slow ....... you down and is frustrating ..... to watch lol

[@edwardhannigan6324]

Top fix Terry..Great video and thanks for sharing your knowledge..Ed..u.k...😀

[@tjsogmc]

That's a slick trick. But I like to remove the board anyways anytime I have to make a repair like that so I can inspect the solder joints. It's amazing what you find sometimes. Every broken or dry joint I fix is one problem that I won't have later on. It's worth it to me to take the time to inspect the underside of the board for just that reason.

[@glenndavis6793]

You're the man Terry

[@miguelrichartmellado2834]

Thanks Terry ! Fantastic channel.

[@billyrey9679]

Super nice job!

[@stephensallak2059]

Re: your professional anecdote... There's no work like rework. 👍

[@d-labelectronics]

Yes Sir, we call them redo loops

[@jackvai2681]

THANK THE GODS FOR TRIODE!

[@peterday7077]

Maybe sometime you could show us how to install a pre-phase inverter master volume on a Marshall.

[@NINEWALKING]

Pre PI Master Volume install is way easier. All you need is single 1MOhm Audio/logarithmic potentiometer and some shielded cable. All you need to do is take the wire from the middle pin of the treble pot and connect it to a slider of the new pot. Then connect that treble pot slider/middle lug to the top lug of the new pot. Last step is ground the lower lug of the new pot. Use shielded wire and ground it only from one side. There you go. There is a lot of discussion on pre and post PI master volume pots. If you are reducing power output stage and want preamp distortion only it will never sound as good as with the distortion from the power stage. Many pro players will tell you that Marshall Plexi tone is that not there when the whole amplifier is creating the distortion and is begging for its life. Non experienced players don’t anticipate that huge Plexi headroom and bone crashing volume that comes with the 100 Watt Plexi and half or God forbid full stack. If you can’t use it get the 50 Watt version and the load box. Or get 18 Watt Bluesbreaker. Some people will advise yellow jackets adapters and EL84 tubes. Some people will note that some amps can work with 2 tubes only. Sure both versions will reduce power but will omit output transformers distortion. Part of the output stage distortion is in the saturation of the output transformer. It adds sort of compression and it shows best on highest volume. Two tubes or 4x EL84 can’t do that. Marshall Plexi Super Lead 100 Watt with the full stack at 10 feet away will scare every player first time you experience it. You will think that you are going to explode. Sadly before that level those amplifiers sound just extremely loud and clean. Even to get them t the edge of the breakup volume levels will be scary high. So choose your amplifier according to your needs and venues where you play. 100 Watt Plexi at home is nice to have but almost useless. You want know what you have until you let it spread its wings.

[@Cpt_Adama]

I'd go with the lock washer, looks better than the hole.

[@tubeDude48]

Nice!

[@markn4526]

Good info. Isn't this Super Lead a reissue 1959?

[@debbozell6639]

I have a whites coin master 6000/Di professional series metal detector with an empty battery pack . No connection points or anything except to wires at the top of the case inside that have been clipped , I believe for recharging. Is there anyway I could rebuild this so that I can use my detector? Can I purchase the things I need to do that and is there a charger still available? I have search all over the web for a battery or replacement and can’t find one anywhere. Help please!

[@peterk743]

Awesome!

[@josephwzappia]

Hi, great video,. Would this work on a Marshall SV-20h ? thank you.

[@Curtislow2]

5:12 is the diagram .FYI

[@isexuallyidentifyasanovenm1617]

I used this video as a reference when putting in my ppimv. Im having issues though. Everything is connected exactly how it should be but when checking the terminals to ground like you did, i was getting resistance, which you said is indication of a short, but for the life of me there isnt anything that could possibly be causing a short so im kind of at a loss right now trying to figure it out

[@R3TR0R4V3]

That'll work on a 1987X? I have a early 2000s reissue I thought about doing this to.

[@GL64]

Yup I've done it on my own 1987x

[@lousekoya1803]

Thank you !

[@upholsterybycarlos]

hello < nice video, where I can buy the 250k volume control ??? I have 100w Marshall plexi and I can't enjoy because is to loud for my hear.

[@stevewatson1599]

Hi Terry, how about pre-wiring the coax & resistors to the pot prior to installation in the chassis?

[@d-labelectronics]

Yes, That would streamline the operation

[@danielsaturnino5715]

Nice walkthrough. So that master volume is just a power tube bias control? Thanks Terry.

[@d-labelectronics]

Nope, Bias remains constant, the signal is just attenuated

[@kbkman7742]

They mix each side of the output signal together which cancels it out.

[@jamiem3279]

@@d-labelectronics When you turn the master volume towards 0, it lowers the resistance in the bias circuit, which apparently isn't a problem. But it does make me wonder why they had the two 220kΩ resistors in the circuit in the first place.

[@TheAlpineProject]

Is this the same layout as the 1970's PCB 100w Super Leads?

[@Aceandbob23]

Update: I have -140v on the grids on pin 4 How can the negative voltage go across the pot if it's on full? All the way off, the pot gives the negative voltage straight to the tube but how does it go to the grids if the pot is full on? I'm doing this mod at the moment and it got me a bit concerned since I'm almost done. Thanks!

[@tremdoctor007]

Nicely done. I’d like this on my Marshall DSL100H. I use a JHS Little black box to accomplish the same thing. I also want to move the Pentode/Triode switch from the back to the front replacing my Standby m/On switch. My local tech says I can’t. I can’t see why, the back is a switch, tge front is a switch. The front switch on the HR Model is a 3 way, low/standby/high. Just switch differences. I ordered their Marshall 3 way used on the newest DSL HR heads. Anyone else try this?

[@hrsey71]

my MV is wired differently from this, but i cant figure out which type it is.. the orange and green wires are still connected to the board, and go to the dual gang pot. another wire goes from the dual gang pot to the spot where the 2 resistors are removed. then 2 wires go to the 2 tube sockets. any idea what this type is?

[@johnb4024]

Hey Terry, some people complain about master volumes not sounding right because of the negative feedback reduction. Do you recommend any kind of NFB mods whether on a potentiometer or switch?

[@kurtslilgirl]

how to mod it for clean tones only

[@jessek.beauchamp1356]

Hi, I have a fender BassBreaker 30r combo, Kendrick once told me there was a mod to place a master volume near the phase inverter in a bassman or a 79 silver face dlx. Can you figure out where to place a Master just like this. Same place. Thanks.

[@d-labelectronics]

Sorry man, never worked on that model

[@richard66754]

My plexi doesn’t make anywhere near as much white noise as that one. I wonder if something is wrong with his amp? Maybe I’ve just never listened that closely.

[@waldemarpierzchalski]

Is this called larmar ppimv?

[@Legend_Randy]

Will this work on a marshall studio vintage 20 plexi?

[@wlrIII]

Does anyone know how master volume compares to power scaling sound-wise?

[@leonardwilson980]

Hi Terry. I have a question if you don't mind. I have a Fender Champion 100 with the tap button for setting all the speed effects. My question is. Can it be replaced with a pot?

[@d-labelectronics]

Sorry man, That PCB tech cannot be bypassed with a pot

[@leonardwilson980]

@@d-labelectronics Thanks Terry, It's the only think I don't like on the amp

[@tremdoctor007]

Nicely done. I’d like this on my Marshall DSL100H. I use a JHS Little black box to accomplish the same thing. I also want to move the Pentode/Triode switch from the back to the front replacing my Standby m/On switch. My local tech says I can’t. I can’t see why, the back is a switch, tge front is a switch. The front switch on the HR Model is a 3 way, low/standby/high. Just switch differences. I ordered their Marshall 3 way used on the newest DSL HR heads. Anyone else try this? Subscribed!! Nice video

[@Ken-wd4wk]

sorry off topic, but I am going to add mp3 to my vintage 1005 chassis . saw on your vids 1st way is (2) 47k ohm then another way was (2) 1k ohm and a 10k ohm to ground for input any major reason why 2 different ways ?? .//// Thnx ken

[@PoppysGuitar]

Doug can't you just remove one of the speaker jacks?

[@Mega_trav]

Hey D-Lab, I know you don’t always like circuit boards. Do you prefer tag board, turret board, etc?

[@d-labelectronics]

eyelet boards are my fav

[@shredding51]

I guess this will work on a 1987x?

[@PoppysGuitar]

"you just use an 8th inch hole" at 3:19. Terry what in the heck does that mean? Sorry. Great Video btw.

[@indioflechudo6221]

nice

[@cgavin1]

The problem with those dual gang pots is they are so darn large. Had a nightmare getting them in to old Fenders.

[@Einzatskommando]

That's why you use Marshall 🤭

[@cgavin1]

@@Einzatskommando Its true but at least I can derive satisfaction from the fact she's still tight after 50 years.

[@michaeldowning796]

When I do these master volume installs, I remove one of the speaker jacks and move the presence knob to the rear and install the master in the presence position on the front panel No holes drilled and fully reversible

[@Wizardofgosz]

Wait, WHAT??! An amp that doesn't come with a master volume? That's weird, right?

[@jeffreycollins7297]

WHY, they were made to be played LOUD at concerts, they weren't made to be played in bedrooms.

[@Wizardofgosz]

@@jeffreycollins7297 well then you'd better explain that to every other amp in the world that comes with a master volume

[@trefwoordpunk2225]

@@Wizardofgosz These amps were designed before the concept of a master volume was even invented! 100W Marshalls came about because guitarists of the day were asking Marshall for LOUDER amps....it wasn't until the 70s that master volumes came into being (1976 was when the first Marshall with a master volume came out I think).

[@Tonetwisters]

Seems like Marshall led the way with PCB's ...

[@analogblues9606]

Hi Terry, yes please email me the jpeg. Thanks

[@jeffreycollins7297]

For an amp like that MV is cool, but i'd rather just have a THD hot plate or some other kind of break for the amp to feed into.

[@PoppysGuitar]

why?

[@josephmartinez3851]

Oh yes I be 🥇.....

[@TheTrueVoiceOfReason]

I've got a story... Bout a man named Jed Poor mountaineer Barely kept his family fed Sorry, wrong video. :)

[@ronjinks8932]

This is a totally useless endeavor. While this will enable lowering the volume, it will result in no difference to lowering the input .

[@jubyerhashin8214]

Circus board 🤡