If this was my amp I wouldn’t hesitate to swap out those 82K splitter-resistors, since in conjunction with the 0.022uF coupling caps they create a quite noticeable high pass filter. If fitting the amp with EL34s, I would go for 220K. Also check that the volume pots have a logarithmic taper. For some reason a lot of 75 Marshalls came with linear 1M pots.
I now because of you, I am making sure all components are tightened down well. I did it before ,but now I am always doing it when I do a twice the year clean and maintenance on my amps and guitars. Thanks for the help. 5:31
MY FAVORITE AMPS SINCE CHILDHOOD!!!! 1987 AND 1959 SUPERLEAD'S.....GOLDEN TONE!!! THANKS FOR ALL YOUR EXPERTISE IN KEEPING THESE AMPS THE BEST THEY CAN BE .....LOVE YOUR CHANNEL!!! ❤
@@qua7771 That and the WARMTH and PUNCH....a post phase master volume is a must to get great overdrive at a level that doesn't destroy your hearing (even though my ears always ring after I play regularly loud....got to get the half stacks moving air and power tubes adding their tone)
@@curtisprice9806 Yes, sir. I have a '68 Ceriatone build. It works amazingly for everything I care to play. I used the best parts I could find. I added a little more gain to V1. These seem to like NOS/ vintage glass. I've been using modern greenbacks though. I'm considering checking out Weber pre-rola clones.
That is one pristine '75 Marshall! Very cool. And if anyone has a DSL, make sure to tighten the transformer hold down screws - if they are loose, they hum and buzz.
I’ve had a ‘75 lead and bass 50 head for a few years now and can’t believe I’ve never looked inside..lol It doesn’t have the original iron so I guess I never felt precious about what the guts looked like as the amp sounded good…..feeling inspired now.
Thanks for that transformer tightening tip. Just went through my '79 2204 and found a couple of loose bolts. In fact, this past May it celebrated it's 45th year, and will celebrate it's 45th year in my possession in July. A great amp that really picked up when I switched to EL34s, and now using KT77s. I do all my servicing, but always look forward to your video for more tech tips!
Seems like you could make a replacement for that impedance jumper with a couple of nice fitting banana plugs (or something) that works well, keeping thing otherwise unchanged.
Those old jumper plug impedance selectors were never a great idea. I've installed a plate with a DPDT switch in the past to permanently fix the issue. The new selectors that are available now don't fit right and have problems of their own.
I have a '95 1987X reissue with a master volume on the back and I wish they put it on the front so I don't lose the second output. Love your channel and sharing your knowledge!
Thanks Ryan. I’d drill a new rear panel hole in a reissue but I’m not drilling this original. I’d gladly make the owner a small 1 in 2 parallel out box to replicate the original two output jacks, but it’s rare for anyone to use two cabs these days.
TAD offers a drop-in replacement switch and mounting plate with vintage correct holes. Haven't done it on my own 1986 (converted to 1987), but I just ordered it after watching this video. It was €30 including shipping to another EU country, so not cheap, but not unobtainable either.
Not sure. The really good rotary one went off the market a few years back - that’s the one TAD lists as out of stock. The one they’re selling now might be as good as any rotary these days - certainly better than the one they sell as Bogner style. Those break. My preference is a good DPDT switch instead of a 3 position rotary.
@@PsionicAudio Thanks a lot for all this information. I would guess that a DPDT switch would leave the owner with only 2 options for impedance, but as it's rare to use all three I suppose it makes sense!
Consistency was not Marshall's strong suit. You cant identify them by cosmetic differences as easily as you can Fenders. Also the model designation numbers are notoriously confusing. I swear they were trying to confuse people with them. Lets identify the models with a number that sounds like a year! Great idea! Really few amp manufacturers done things as well as Fender on alot of things and documentation/ identification is just one aspect of that.
Something to think about. For adding a selector switch on the back a tube socket blank plate cover matches up with holes on the chassis. This will allow you to install the plate from inside the amp and drill a 3/8 hole and install the selector switch. Then purchase a selector knob that looks like the original.
Regarding those metal tube retainers - how about putting a dot of silicone caulk at the points of contact so as to create little bumpers between the metal and the glass? There's a light fixture over our breakfast nook here and I am always bumping my head into one of the 10 hanging glass globes. I added a dot of silicone to the two places where they collide, and now when it inevitably happens, there is no damage, barely any sound, even.
I am hoping it has a bit of hiss on the treble channel and the amp squeals when the presence is turned right up if the amp is running loud. Then I might have more of an idea what's up with my JMP 50 build. The guy who built it went to replica lengths using mustard caps etc. Hopefully they are not the culprits, because I like how they look.
Hey Lyle your audio is very bassy in this video. I listen with a surround sound system that has a subwoofer but that is not it. Not trying to rag on you but I know you like to know how things are sounding. Love the content though! I have a 1970 Super Bass that I converted to SL with NOS mustards and period correct resistors, etc. Mine came with a pre PI master, I kept it because I love how it stays cleaner with that one and I also put in a Post PI master and a bright cap selector switch. It is so nice to be able to have all of the options with both masters along with the channel volumes it is so versatile now. Thank you for the awesome videos!!!
Thanks Scott. I was trying a different overhead mic setup at the bench to get fewer reflections off all the hard flat surfaces, and I guess there was too much proximity. I was editing at a moderate volume because it was late at night, so I didn’t hear it. This was with a highpass at 130Hz! I’ll try not to drop into my most relaxed range when doing these. It can be a lot for any mic.
@@PsionicAudio It can be hard taming your natural James Earl Jones voice frequency range I'm sure LOL wink wink. We are glad you put in the time and effort to make great vidoes !! And it is nice to see the care and integrity going into all of your work!!
@@scottjamable, Back in the 80's people used to joke that James Earl Jones' voice was so wonderful he would be entertaining just reading the phone book, and so there was a skit on Saturday Night Live where he was the guest host and did just that, reading the phone book to little kids at bedtime!
I've been toying around with both pre- and post- PI mastervolumes in my own '74 1986. It becomes a lot of gain stage knobs it it would make it an absolutely awesome amp for both studio, live, and practice.
@@lordgraga yeah like today I cranked my post PI master and turned down my pre pI master to clean the amp up almost into fender territory or blend in a little post and vise versa. Blending the two together along with the two stock channel volumes let’s this amp be anything you want. I would recommend this to anyone. Also having a smaller bright cap selectable with the stock cap takes any unwanted hair away when your trying to clean up the amp turned down. I use a 331pF on a switch with the stock 500pf. Good stuff!
The value stamped on the end caps of fuses is so small and sometimes somewhat indistinct that my old eyes usually require a magnifying glass and strong light to read them.
Just a quick question, how the hell could those nuts be tightened for the on/off/standby switch? I bet there is a reason for those indents but I'm always struggling with those. Cheers!
A dab of "blue" thread locker would cure the loose transformer bolt ass'y problem.....permanently. The crescent wrench (which was being used upside down, at one point) is the perfect tool to straighten that bent chassis ear.....I'm gonna assume you'd know how. A hammer and a block of wood!?! Good Lord......NEVER! 😮
@PsionicAudio 🤣🤣 man I loved that show as a kid. I need some reruns now. Been a long time. On a serious note Lyle, how were the traces on this amp? When did Marshall start getting cheap with their PC boards?
Beautiful. Marshall is like the only thing that makes me proud to be British. That thing is perfect.
If this was my amp I wouldn’t hesitate to swap out those 82K splitter-resistors, since in conjunction with the 0.022uF coupling caps they create a quite noticeable high pass filter. If fitting the amp with EL34s, I would go for 220K.
Also check that the volume pots have a logarithmic taper. For some reason a lot of 75 Marshalls came with linear 1M pots.
I now because of you, I am making sure all components are tightened down well. I did it before ,but now I am always doing it when I do a twice the year clean and maintenance on my amps and guitars. Thanks for the help. 5:31
MY FAVORITE AMPS SINCE CHILDHOOD!!!! 1987 AND 1959 SUPERLEAD'S.....GOLDEN TONE!!! THANKS FOR ALL YOUR EXPERTISE IN KEEPING THESE AMPS THE BEST THEY CAN BE .....LOVE YOUR CHANNEL!!! ❤
What I built my replica from. I keep going back to it after trying other amps. Something about the note definition.
@@qua7771 That and the WARMTH and PUNCH....a post phase master volume is a must to get great overdrive at a level that doesn't destroy your hearing (even though my ears always ring after I play regularly loud....got to get the half stacks moving air and power tubes adding their tone)
@@curtisprice9806 Yes, sir. I have a '68 Ceriatone build. It works amazingly for everything I care to play. I used the best parts I could find. I added a little more gain to V1. These seem to like NOS/ vintage glass. I've been using modern greenbacks though. I'm considering checking out Weber pre-rola clones.
Glad to see your channel growing,and rightfully so 🇺🇸
That is one pristine '75 Marshall! Very cool. And if anyone has a DSL, make sure to tighten the transformer hold down screws - if they are loose, they hum and buzz.
I’ve had a ‘75 lead and bass 50 head for a few years now and can’t believe I’ve never looked inside..lol It doesn’t have the original iron so I guess I never felt precious about what the guts looked like as the amp sounded good…..feeling inspired now.
Replaced iron is fairly common.
Yes, I agree, a beautiful amp indeed. I have one exactly like this, this is like looking at it's twin
Little envy.
Very beautiful indeed! It's good to know that it's fallen to you to make it amazing again!
Thanks for that transformer tightening tip. Just went through my '79 2204 and found a couple of loose bolts. In fact, this past May it celebrated it's 45th year, and will celebrate it's 45th year in my possession in July. A great amp that really picked up when I switched to EL34s, and now using KT77s. I do all my servicing, but always look forward to your video for more tech tips!
That was Fun. Thanks Lyle.
Those transformers are massive !
Seems like you could make a replacement for that impedance jumper with a couple of nice fitting banana plugs (or something) that works well, keeping thing otherwise unchanged.
Those old jumper plug impedance selectors were never a great idea. I've installed a plate with a DPDT switch in the past to permanently fix the issue. The new selectors that are available now don't fit right and have problems of their own.
I have a '95 1987X reissue with a master volume on the back and I wish they put it on the front so I don't lose the second output. Love your channel and sharing your knowledge!
Thanks Ryan. I’d drill a new rear panel hole in a reissue but I’m not drilling this original. I’d gladly make the owner a small 1 in 2 parallel out box to replicate the original two output jacks, but it’s rare for anyone to use two cabs these days.
@@PsionicAudio You _could_ also bridge the inputs internally, and then use the normal inputs for a MV pot. It changes the look but it's reversible.
TAD offers a drop-in replacement switch and mounting plate with vintage correct holes. Haven't done it on my own 1986 (converted to 1987), but I just ordered it after watching this video. It was €30 including shipping to another EU country, so not cheap, but not unobtainable either.
Thanks, switch looks a little iffy but the plate would be nice.
@@PsionicAudio what switch would you recommend then?
Not sure. The really good rotary one went off the market a few years back - that’s the one TAD lists as out of stock. The one they’re selling now might be as good as any rotary these days - certainly better than the one they sell as Bogner style. Those break.
My preference is a good DPDT switch instead of a 3 position rotary.
@@PsionicAudio Thanks a lot for all this information. I would guess that a DPDT switch would leave the owner with only 2 options for impedance, but as it's rare to use all three I suppose it makes sense!
Thank you Sir.
Consistency was not Marshall's strong suit. You cant identify them by cosmetic differences as easily as you can Fenders. Also the model designation numbers are notoriously confusing. I swear they were trying to confuse people with them. Lets identify the models with a number that sounds like a year! Great idea! Really few amp manufacturers done things as well as Fender on alot of things and documentation/ identification is just one aspect of that.
Something to think about. For adding a selector switch on the back a tube socket blank plate cover matches up with holes on the chassis. This will allow you to install the plate from inside the amp and drill a 3/8 hole and install the selector switch. Then purchase a selector knob that looks like the original.
I’ve done similar in the past. Not sure an octal blank will line up but I’ll see.
Ouch the crescent hammer. I’m surprised to see use that. My knipex channels have replaced my crescent hammers. Lot less damaging to hardware👌
"Your currancy may vary" Priceless. HA!!!
Lovely!
I do agree.
Mahalo Lyle! Nice amp.
Great video!
Regarding those metal tube retainers - how about putting a dot of silicone caulk at the points of contact so as to create little bumpers between the metal and the glass?
There's a light fixture over our breakfast nook here and I am always bumping my head into one of the 10 hanging glass globes. I added a dot of silicone to the two places where they collide, and now when it inevitably happens, there is no damage, barely any sound, even.
I am hoping it has a bit of hiss on the treble channel and the amp squeals when the presence is turned right up if the amp is running loud. Then I might have more of an idea what's up with my JMP 50 build. The guy who built it went to replica lengths using mustard caps etc. Hopefully they are not the culprits, because I like how they look.
Hey Lyle your audio is very bassy in this video. I listen with a surround sound system that has a subwoofer but that is not it. Not trying to rag on you but I know you like to know how things are sounding. Love the content though! I have a 1970 Super Bass that I converted to SL with NOS mustards and period correct resistors, etc. Mine came with a pre PI master, I kept it because I love how it stays cleaner with that one and I also put in a Post PI master and a bright cap selector switch. It is so nice to be able to have all of the options with both masters along with the channel volumes it is so versatile now. Thank you for the awesome videos!!!
Thanks Scott. I was trying a different overhead mic setup at the bench to get fewer reflections off all the hard flat surfaces, and I guess there was too much proximity. I was editing at a moderate volume because it was late at night, so I didn’t hear it.
This was with a highpass at 130Hz!
I’ll try not to drop into my most relaxed range when doing these. It can be a lot for any mic.
@@PsionicAudio It can be hard taming your natural James Earl Jones voice frequency range I'm sure LOL wink wink. We are glad you put in the time and effort to make great vidoes !! And it is nice to see the care and integrity going into all of your work!!
@@scottjamable, Back in the 80's people used to joke that James Earl Jones' voice was so wonderful he would be entertaining just reading the phone book, and so there was a skit on Saturday Night Live where he was the guest host and did just that, reading the phone book to little kids at bedtime!
I've been toying around with both pre- and post- PI mastervolumes in my own '74 1986. It becomes a lot of gain stage knobs it it would make it an absolutely awesome amp for both studio, live, and practice.
@@lordgraga yeah like today I cranked my post PI master and turned down my pre pI master to clean the amp up almost into fender territory or blend in a little post and vise versa. Blending the two together along with the two stock channel volumes let’s this amp be anything you want. I would recommend this to anyone. Also having a smaller bright cap selectable with the stock cap takes any unwanted hair away when your trying to clean up the amp turned down. I use a 331pF on a switch with the stock 500pf. Good stuff!
I just missed out on a 75 superlead for 1800 canadian .. would have been so fun to service it and then get evicted shortly after. Ugh
The value stamped on the end caps of fuses is so small and sometimes somewhat indistinct that my old eyes usually require a magnifying glass and strong light to read them.
Hi! do you have a favourite ceramic (or mica) cap to replace bright and slope caps? lemcos are hard to find these days. Thanks!
Just a quick question, how the hell could those nuts be tightened for the on/off/standby switch? I bet there is a reason for those indents but I'm always struggling with those. Cheers!
Special wrench or adjust the nut inside the chassis.
A fukin crescent wrench ? I thought U were a professional
At least I can spell fuck. And you.
A dab of "blue" thread locker would cure the loose transformer bolt ass'y problem.....permanently.
The crescent wrench (which was being used upside down, at one point) is the perfect tool to straighten that bent chassis ear.....I'm gonna assume you'd know how. A hammer and a block of wood!?! Good Lord......NEVER!
😮
Upside down?! The horror!
Block of wood won’t leave a mark on the metal flange. A tool can.
😎👍
i have a similar era model. the leads from the PT/OT are very thin! this worries me
Wish my 50 watt JCM looked that good. One too many beer soaked gigs.
But does it go to eleven?
🤣🤣
Many 6550's have metal collars on the base; are there bear traps that will fit those?
Stay tuned.
@@PsionicAudio , Same bat time, same bat channel!
And right after that, cue the Get Smart theme…
I hate it when my knobs aren't on the same plane. Painful!
@PsionicAudio 🤣🤣 man I loved that show as a kid. I need some reruns now. Been a long time. On a serious note Lyle, how were the traces on this amp? When did Marshall start getting cheap with their PC boards?
Look at the beefy transformers
LYLE!!!! Shazaaaaam!