Any truth to the rumor that Marshall amps built after 73 sound thinner?
- Thread starter 75lespaul
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AdmiralB
New member
Re: Any truth to the rumor that Marshall amps built after 73 sound thinner?
The circuit didn't change when they went to the PCB. Various running changes were instituted over time starting circa-'67 and pretty much completing by late 1970, and yes, a typical '71 Super Lead will be brighter and more aggressive than a typical, say, '68, but by '71 the design was pretty well sorted out.
The circuit didn't change when they went to the PCB. Various running changes were instituted over time starting circa-'67 and pretty much completing by late 1970, and yes, a typical '71 Super Lead will be brighter and more aggressive than a typical, say, '68, but by '71 the design was pretty well sorted out.
shredaholic
New member
Re: Any truth to the rumor that Marshall amps built after 73 sound thinner?
Maybe, but it's not because of the circuit board type. That has no discernable effect on tone.
Maybe, but it's not because of the circuit board type. That has no discernable effect on tone.
Gearjoneser
Gear Ho
Re: Any truth to the rumor that Marshall amps built after 73 sound thinner?
It's when they went from 4 input heads to mid 70's MKII Master Volumes that the main tone changed. The Master volumes from the mid and late 70's have a little more gain, but sort of a thinner sound. Then when the 800 series started, they sounded a little better, but it's a generalization. I've heard Marshalls of all eras with fresh tubes that sounded great, and some that sounded like a Valvestate. I wonder why, myself.
One theory I've had is that many amps in that era had 6550's, and when techs switched them over to EL-34's, they failed to optimize the circuit so those tubes would sound as good as possible. I dunno.
It's when they went from 4 input heads to mid 70's MKII Master Volumes that the main tone changed. The Master volumes from the mid and late 70's have a little more gain, but sort of a thinner sound. Then when the 800 series started, they sounded a little better, but it's a generalization. I've heard Marshalls of all eras with fresh tubes that sounded great, and some that sounded like a Valvestate. I wonder why, myself.
One theory I've had is that many amps in that era had 6550's, and when techs switched them over to EL-34's, they failed to optimize the circuit so those tubes would sound as good as possible. I dunno.
STRATDELUXER97
Stratoblaster Tone Meister
Re: Any truth to the rumor that Marshall amps built after 73 sound thinner?
The change from PTP to PCB happened around mid 73 year....I have a pcb version 73 that I converted to PTP...
No tonal differences between pcb vs ptp..
The change from PTP to PCB happened around mid 73 year....I have a pcb version 73 that I converted to PTP...
No tonal differences between pcb vs ptp..
Re: Any truth to the rumor that Marshall amps built after 73 sound thinner?
Look, PTP sounds better - NO LIE
I have a 73 PTP
that being said, these amps are soooooo inconsistent. They do get a bit brighter thru the 70s - but that helps it sound gainier if you ask me. I have played some 68 - 69 plexis both 50 and 100w and they do sound creamy/creamier, but I have heard people rock the universe thru mid 70s models. I think late 70s models are a bargain, and you can spruce them up. A lot of the late 70s MVs sound better than JCM800s, AND they look cool!
You never truly know what a Marshall sounds like til you crank, or at the very least HOT PLATE it. They get juicier as you blast 'em.
So if you find a killer Marshall - GET IT! It IS the SOUND of ROCK!
Look, PTP sounds better - NO LIE
I have a 73 PTP
that being said, these amps are soooooo inconsistent. They do get a bit brighter thru the 70s - but that helps it sound gainier if you ask me. I have played some 68 - 69 plexis both 50 and 100w and they do sound creamy/creamier, but I have heard people rock the universe thru mid 70s models. I think late 70s models are a bargain, and you can spruce them up. A lot of the late 70s MVs sound better than JCM800s, AND they look cool!
You never truly know what a Marshall sounds like til you crank, or at the very least HOT PLATE it. They get juicier as you blast 'em.
So if you find a killer Marshall - GET IT! It IS the SOUND of ROCK!
Lake Placid Blues
New member
Re: Any truth to the rumor that Marshall amps built after 73 sound thinner?
With 6550's the negative feedback loop is connected to the 4-ohm lug instead of the 8 ohm lug, and IIRC, the NFB resistor is different value. Besides making it possible to properly bias the amp when swapping tube types, the NFB loop should also be adressed. Many techs do over look this.
Marshalls got a little brighter during the 70's, but not necessarily thinner. Perhaps brighter is precieved as thinner? 6550's sound cleaner and brighter too.
Gearjoneser said:
With 6550's the negative feedback loop is connected to the 4-ohm lug instead of the 8 ohm lug, and IIRC, the NFB resistor is different value. Besides making it possible to properly bias the amp when swapping tube types, the NFB loop should also be adressed. Many techs do over look this.
Marshalls got a little brighter during the 70's, but not necessarily thinner. Perhaps brighter is precieved as thinner? 6550's sound cleaner and brighter too.
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75lespaul
New member
Re: Any truth to the rumor that Marshall amps built after 73 sound thinner?
Great stuff. Back in the mid-eighties when I was first introduced to the whole plexi phenomenon, the VERY small group of people I knew were so against tremelo models and pcb models, I steered clear of them unheard. I was young and really had no reason to doubt these people who seemed to have so much more experience than me with amps. I had my JCM 800 but when we did a side by side comparison with a 68 plexi with matching greenback cab, the plexi just smoked the JCM800. But then, putting the JCM800 through the plexi cabinet made it sound a lot like the plexi, but with more gain.
I'm not looking for one now as my Univox and Bassman amps with my Plexitone give me the sound and I don't have the cash to collect them, but over the years I passed up on a LOT of great deals when I was living at home and could afford to blow my cash on nothing buy partying and music gear. Oh the misinformation, LOL. This was a time when in my area (no ebay of course--no internet!) the Plexi was getting unafordable and the JCM800s were new, so they were pricey, but the mid to late 70s amps were affordable and I literally could have hoarded about five during that time. Don't even get me started on the blackface fenders I could have had for $300.
It's great to see young people on this forum getting great information and not making the same mistakes I did. If I had a forum like this in 85, I surely would have asked this question 21 years ago. :kabong:
Great stuff. Back in the mid-eighties when I was first introduced to the whole plexi phenomenon, the VERY small group of people I knew were so against tremelo models and pcb models, I steered clear of them unheard. I was young and really had no reason to doubt these people who seemed to have so much more experience than me with amps. I had my JCM 800 but when we did a side by side comparison with a 68 plexi with matching greenback cab, the plexi just smoked the JCM800. But then, putting the JCM800 through the plexi cabinet made it sound a lot like the plexi, but with more gain.
I'm not looking for one now as my Univox and Bassman amps with my Plexitone give me the sound and I don't have the cash to collect them, but over the years I passed up on a LOT of great deals when I was living at home and could afford to blow my cash on nothing buy partying and music gear. Oh the misinformation, LOL. This was a time when in my area (no ebay of course--no internet!) the Plexi was getting unafordable and the JCM800s were new, so they were pricey, but the mid to late 70s amps were affordable and I literally could have hoarded about five during that time. Don't even get me started on the blackface fenders I could have had for $300.
It's great to see young people on this forum getting great information and not making the same mistakes I did. If I had a forum like this in 85, I surely would have asked this question 21 years ago. :kabong:
shredaholic
New member
Re: Any truth to the rumor that Marshall amps built after 73 sound thinner?
Why? Because Marshall told you so? Have you ever directly tested the two types of board with EXACTLY the same components (inc tolerances) used on both boards?
There's no scientific reason why a PTP should sound better than a well made PCB. PTP's are easier to mod, which is why I have one in my amp, but the amp would sound just the same if I took all the components on that board and put them on the old PCB.
OlinMusic said:
Why? Because Marshall told you so? Have you ever directly tested the two types of board with EXACTLY the same components (inc tolerances) used on both boards?
There's no scientific reason why a PTP should sound better than a well made PCB. PTP's are easier to mod, which is why I have one in my amp, but the amp would sound just the same if I took all the components on that board and put them on the old PCB.
Re: Any truth to the rumor that Marshall amps built after 73 sound thinner?
NO particular reason besides that perhaps the odler ones were made better or with different components
I wasn't saying PTP sounds better
I should have rephrased to say THE EARLY YEARS, which HAPPEN to be POINT TO POINT
I have A/B's a 1968, 1973, 1975, 1977(MV), and a new JCM 800 all at or about the same time. I prefered the 1968 and 1973 the most.
Like I've said many times, I also love Bogners and thosse are PCB.
I think the HWs are creamier than the regular RI's which seem a tad more harsh. Then again, I actually like having an FX loop like the 1987x and 1959x
I was also making the argument that ANY 70s Marshall can possibly sond like the holy grail, but they are so inconsistent, and many need work - but I feel if you search, you can very likely find THE sound.
NO particular reason besides that perhaps the odler ones were made better or with different components
I wasn't saying PTP sounds better
I should have rephrased to say THE EARLY YEARS, which HAPPEN to be POINT TO POINT
I have A/B's a 1968, 1973, 1975, 1977(MV), and a new JCM 800 all at or about the same time. I prefered the 1968 and 1973 the most.
Like I've said many times, I also love Bogners and thosse are PCB.
I think the HWs are creamier than the regular RI's which seem a tad more harsh. Then again, I actually like having an FX loop like the 1987x and 1959x
I was also making the argument that ANY 70s Marshall can possibly sond like the holy grail, but they are so inconsistent, and many need work - but I feel if you search, you can very likely find THE sound.
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shredaholic
New member
Re: Any truth to the rumor that Marshall amps built after 73 sound thinner?
Ah well in that case I agree - the older the Marshall, the better the components they tended to use so the better the amps sound. The mustard coloured capacitors started to be phased out in the 70's; these were partly responsible for the killer tone, and the design of the output transformer started to change too.
The reason the HW sounds better than the 1959slp/1987x's is because it uses a slightly better output transformer, better coupling capacitors (Roderstein poly caps instead of those little grey box caps) and a very slightly different circuit (1 or 2 component changes).
Personally I think the same as you on the effects loop - I bought a 1959slp with an effects loop then fitted it with a turret board like the originals (with Sozo capacitors), replaced the output transformer with a Metroamp Dagnall clone (much closer to the original OT's than the one in the HW's actually) and NOS preamp tubes. Now it could eat either a 1959slp or a 1959HW for breakfast!
Ah well in that case I agree - the older the Marshall, the better the components they tended to use so the better the amps sound. The mustard coloured capacitors started to be phased out in the 70's; these were partly responsible for the killer tone, and the design of the output transformer started to change too.
The reason the HW sounds better than the 1959slp/1987x's is because it uses a slightly better output transformer, better coupling capacitors (Roderstein poly caps instead of those little grey box caps) and a very slightly different circuit (1 or 2 component changes).
Personally I think the same as you on the effects loop - I bought a 1959slp with an effects loop then fitted it with a turret board like the originals (with Sozo capacitors), replaced the output transformer with a Metroamp Dagnall clone (much closer to the original OT's than the one in the HW's actually) and NOS preamp tubes. Now it could eat either a 1959slp or a 1959HW for breakfast!
kevlar3000
Bullet Proof Toneologist
Re: Any truth to the rumor that Marshall amps built after 73 sound thinner?
The switch to a spilt cathode ( I think that started in 69??) as well as higher value brite caps made a big difference. Both give you more scream, but also increase treble response. Pickups were getting wound hotter too... It was all about hot rock in the 70s. Values were always changing in those Marshalls. Output coupling caps going from .1 to .022 also make a dramatic difference. The cool thing is that these are all very easy things to tinker with, or to tell a tech to tinker with. The mystery of what made for both good and and bad sounding Marshalls ( which there were many) has really been documented. Simply changing a brite cap value can change the complete personality of an amp... Really fun stuff to mess with.
I completely disagree that PTP sounds better. My PCB Carlsbro, Stramp and Ampeg B25 are amazing sounding heads. As good as any of the PTP amps I have.
The switch to a spilt cathode ( I think that started in 69??) as well as higher value brite caps made a big difference. Both give you more scream, but also increase treble response. Pickups were getting wound hotter too... It was all about hot rock in the 70s. Values were always changing in those Marshalls. Output coupling caps going from .1 to .022 also make a dramatic difference. The cool thing is that these are all very easy things to tinker with, or to tell a tech to tinker with. The mystery of what made for both good and and bad sounding Marshalls ( which there were many) has really been documented. Simply changing a brite cap value can change the complete personality of an amp... Really fun stuff to mess with.
I completely disagree that PTP sounds better. My PCB Carlsbro, Stramp and Ampeg B25 are amazing sounding heads. As good as any of the PTP amps I have.
Gearjoneser
Gear Ho
Re: Any truth to the rumor that Marshall amps built after 73 sound thinner?
I think the whole issue with PTP vs. PC has to do with the quality of parts used.
On early amps, every component was a chunky high wattage resistor or cap.
I freaked out when I first saw the PC board on my Jubilee. Everything is small, like a SS Fender amp. I can only imagine that the Jubilee would sound even better if it had a large tracer board with beefy components. At least it has Drake transformers. The Bogner has a lot of PC circuitry, but all the components are top notch. From listening to it, you couldn't tell if it was PTP or PC.
I know some disagree, and it probably has more to do with the components and circuit, but PC board amps usually sound like they've got a plasticky undertone, whereas PTP sounds more 3-D and wide open. A good example would be to compare the 100W plexi from 97 to one of the new handwired ones. The handwired sounds better to me.
I think the whole issue with PTP vs. PC has to do with the quality of parts used.
On early amps, every component was a chunky high wattage resistor or cap.
I freaked out when I first saw the PC board on my Jubilee. Everything is small, like a SS Fender amp. I can only imagine that the Jubilee would sound even better if it had a large tracer board with beefy components. At least it has Drake transformers. The Bogner has a lot of PC circuitry, but all the components are top notch. From listening to it, you couldn't tell if it was PTP or PC.
I know some disagree, and it probably has more to do with the components and circuit, but PC board amps usually sound like they've got a plasticky undertone, whereas PTP sounds more 3-D and wide open. A good example would be to compare the 100W plexi from 97 to one of the new handwired ones. The handwired sounds better to me.
kevlar3000
Bullet Proof Toneologist
Re: Any truth to the rumor that Marshall amps built after 73 sound thinner?
The difference is not the circuit board though. It is the trannies and different signal caps. If you swapped out your Jub caps, for a set of Sozos, I think you would be amazed at the difference in sonics. By the time I was done with My Plexi RI, ( 1996) that thing sounded as good as any 50 watter I have ever plugged into. New OT and went to 68 specs. I left the circuit board in there. My Laney AOR sounded amazing after I got those goofy lil chicklets out. On the other hand, my Stramp is loaded with these weird lil red caps, I have no idea of who or what they are, but that amp might just take any 100 watt Marshall to the woodshed. That thing does not need Mustards to amaze. That amp has a fairly fragile traces. I think the giant boat anchor Iron in there has a great deal to do with the fact that it kicks such serious booty.
Also, tubes and bias have a huge amount to do with where those amps sits. The original RI were known to be biased extremely cold out of the factory. Cold bias makes for a really lifeless sounding amp.
The difference is not the circuit board though. It is the trannies and different signal caps. If you swapped out your Jub caps, for a set of Sozos, I think you would be amazed at the difference in sonics. By the time I was done with My Plexi RI, ( 1996) that thing sounded as good as any 50 watter I have ever plugged into. New OT and went to 68 specs. I left the circuit board in there. My Laney AOR sounded amazing after I got those goofy lil chicklets out. On the other hand, my Stramp is loaded with these weird lil red caps, I have no idea of who or what they are, but that amp might just take any 100 watt Marshall to the woodshed. That thing does not need Mustards to amaze. That amp has a fairly fragile traces. I think the giant boat anchor Iron in there has a great deal to do with the fact that it kicks such serious booty.
Also, tubes and bias have a huge amount to do with where those amps sits. The original RI were known to be biased extremely cold out of the factory. Cold bias makes for a really lifeless sounding amp.
shredaholic
New member
Re: Any truth to the rumor that Marshall amps built after 73 sound thinner?
Joe - on the Metroamp forum there's a diagram for wiring up a Jubilee with a PTP board if you're interested. You could put Sozos in at the same time too.
It's currently got a PPIMV on it, slightly different from the one David Bray adds but still sounds awesome. The mods work extremely well, you don't even need to rebias if you add a "Rich Mod" PPIMV like the one I added, they're about $8 in the Metroamp.com store and come with a detailed diagram - it's one of the easiest things to do on an amp and requires no previous experience working with amps to add.
Joe - on the Metroamp forum there's a diagram for wiring up a Jubilee with a PTP board if you're interested. You could put Sozos in at the same time too.
OlinMusic said:
It's currently got a PPIMV on it, slightly different from the one David Bray adds but still sounds awesome. The mods work extremely well, you don't even need to rebias if you add a "Rich Mod" PPIMV like the one I added, they're about $8 in the Metroamp.com store and come with a detailed diagram - it's one of the easiest things to do on an amp and requires no previous experience working with amps to add.
