First bright cap difference and now this, how much more awesome can this channel get? Its a jungle out there... My head spins and get stuffed with all different forum opinions. But here you can listen yourself and then decide what fits you, and I dont need to spend €2000 to find out. Priceless! Thanks! *edit* I must say ... I was at your friends place, Ragnar, about 9 month ago and bought his 1968 cab, with pre-rola greenbacks from 69. The basscones 55hz. I restored it from that awful pink color, haha... Looks like new now. But what a good guy he was! Super friendly and nice. And I love the cab! Its your fault I got addicted to the pre-rola sound by the way... ;)
Johan, Thanks very much for this split/shared cathode and the bright cap videos. I have particularly wanted to hear the the two cathode arrangements compared like this. You have done a great service to tone hunters everywhere. You videos are especially useful because they let us hear each tone side by side in immediate succession, instead of trying rewire things, then testing the tones. This video confirmed my own experiments: the differences between share/split cathode are much more minimal compared with the differences between various bright caps (and no bright caps). My own preference is for a Bass spec amp, but with shared cathode and switchable bright caps. If you use a Y-cable to input the guitar in both top jacks (instead of jumpering or just plugging into one input) there is much more treble in the tone, so for that setup bypassing the bright cap sounds best, Even with the volume cranked it makes a big difference to my ears and fingers to not have the cap.
Another great video, thanks for constantly adding informative and interesting content. I don't get how you at the moment "only" have 65k subscribers, it should have been at least 650k.
Once again you prove to be a master. Exactly right pairing the les paul with the super lead and the strat with the super bass. Classic tones right there. As a mutual lover of the jmp2204 mv, a 77 to be exact, I'd love to see more of your tone adventures around that amp with different carbs, etc. The jmp2204 and 2203 were on most of the great albums of the late 70s thru early 80s.
I haven't been to your site in a while Johan, the fanboys were gettin' a little thick, but damn, the content is so good I just can't keep passing by! I hove not watched this whole video yet but I predict a couple of things: A stellar representation of what a Marshall really sounds like in the hands of a Marshall guru.I also predict as a rockheaded kid in the 70s and only ever cranked a tube amp to 10 as a starting point and then set the gain. I had a 60's tube Canadian GARNET BTO, a 6ca7 power section behemoth with ugly knobs (WTF?!?!?!?) that I pulled the shafts out of as being stupid and all I didn't realize had set screws (double WTF!?!?!?!?) so I had my brother rig it cranked balls out including pull boosts, and went on jammin with an amp with NO adjustment knobs anywhere, so it was cranked up and on fire, or off. And I used it for a couple years at least, until being stupid as I stated earlier, and also a rockhead playing in a heavy rock band , I blew a fuse and did what the experts and nerds (bah. what do those loooosers know, I'm a freakin rocker to the end, metal or die'etc) said never to do, but man, it was in the middle of a ripping rehearsal, I removed the fuse and covered it in cigarette foil. Don't EVER do that. Of course a spectacular failure of epic but devastating proportions happened and among maybe everything else the transformer lasted maybe a second. So it was onto a Fender Twin, and then the usual suspects of the day, Ampeg V4, Hiwatt Custom 50 (YEAH!!!), Marshall Lead 50, Laney AOR 100, Lee Jackson M1000 Metaltronix, Bogner Alchemist, and the latest, Friedman Smallbox 50 , and the common denominator up until I got the Friedman is that the master might as well as been welded to 10.This windy last section of a gargantuan post leads me to the prediction of what I will choose from your shootout as the king of Marshall classic rock tone will be: Split V1 cathode, and that pesky bright cap won't make much different cranked up, but if it does, cap gone . Finito. Cranked Super Lead with a great player with great taste and great ears and a 50's style Les Paul will equal ROCK AND ROLL SPLENDOR!!! Now to watch and see if I am correct, or maybe just a complete ASS and watch this thing. Let the GAAAAAMES BEGIN!!
The interesting thing is that by adding a few switches to the control faceplate Marshall could have allowed their customers to control these parameters and select whatever sound they wanted. I wonder why Marshall didn’t choose to do that. Many fender amps have a bright switch on them.
Great Video. Love that kind of content. To me, the best would be to have a 1pole on-off-on switch to select between 2 bright cap values or none. Bright caps as you showed have such a big influence. This should be a default control on any amp in by opinion.
Very cool video, Johan! I definitely enjoy these videos, and I am grateful to learn what these small wiring differences make to the overall sound of these amps from your videos! Great stuff!
This is important for people to understand the difference of terminology: what Johan is doing here is NOT a bright cap experimentation project. It is BIASING comparison. A bright cap is placing a small capacitance across a Vol pot so that it allows higher frequencies to "bypass" across the resistance (typically 1Meg) when it's turned down and there's a lot of resistance making the high freq unable to make it through to the next stages of the amp circuit. A BIASING capacitor works completely different. It allows frequencies to be amplified by the tube depending on it's value (keeping this explanation simple to understand). When the value is larger such as 25uF used by Fender it allows the tube to be "fully bypassed" which yields all frequencies to be amplified including the entire low end. Don't confuse a "bypass cap" with a "biasing cap". This is why Fender amps turned up past 5 on the dial begin to distort so much - amplifying the bass frequencies also and towards 10 become flabby and unusable/non-musical. When this capacitor is made much lower like the .68uF used by Marshall (not even 1uF) it only bypasses (amplifies) the higher end frequencies (called shelving affect). This allows you to turn the Vol fully up and since the bass isn't being amplified like the prior example - keeps the tone/guitar nice and tight yielding a more controlled useable gain through the Vol pot's settings.A couple of other considerations to know: as with everything there's always trade-offs. The Marshall biasing will not allow the tube to give full gain throughout all frequencies (this is obvious by the prior explanation) BUT when played loudly with controls up and the amp given more output power you don't need or want this anyway. But in lower Vol settings the amp will not exhibit the same gain as the Fender amps do all things considered. Another is when the BIASING cap is removed you hear a noticeable lowering of Treble response (and tube gain) since these frequencies are also not being amplified further. However - there is a more "smoothness" created without it. This is how amp designers "voice" an amp using multiple stages to have high gain with smoothness Vs it sounding too bright/brittle/fizzy etc. Lastly, when TWO stages share a cathode resistor and bypass cap as in the example and amp in this video - it is extremely important to know that since both stages share you need only 1/2 the resistance & double capacitance to accomplish the same tube operating point (aka BIAS) as would be needed for each one individually (without getting into the math & science behind it). Hope this helps you all a little bit?
Thank you so much for this video. I love modding! I did a Marshall DSL15 once. Would you consider doing a FAQ video so all of us fans could ask questions about you? I have 2 questions: 1. After all the amps that you have gotten to play, what is your favorite to Jan at home with? 2. Being from Sweden have you ever met Peter Svensson (from the cardigans)? He’s one of my favorite guitarists
Thanks! Really good to hear that. 1) the amp I’m using at home is an 83 Marshall JCM800 4010 with a 71 G12H30 55Hz Greenback in it. 2) I haven’t met Peter Svensson but I’m told he’s a Marshall connoisseur like we are. Cheers Johan
Thanks Johan, great comparison. Now, it would be good if you can make a video comparing the influence of tube rectified vs solid state rectified, in the sound of an amp, or if it doesnt matter to affect the tone.
To those that love to tinker and build guitar amps, I think adding a bright cap is one of the easiest mods you can do to get a little more power and sizzle.
I like both and to have them all on lil switches would be nice. I noticed that with split cathode and no bright cap sounded pretty good. Maybe the best of all of them to my ears. I usually set my bass all the way off or very low on my 1969 50 watt smallbox 86 (bass) circuit. I also turn up the presence pretty high around 8. I also owned a 71 super lead and would do A/B comparisons like this. They sounded very very close with the biggest difference to the feel. The super lead was stiffer and tighter while the 50 watt 86 circuit was more organic sounding and spongier. I could feel the 50 react more while I played it. I always asked others around me which sounded better and they always chose the 50 watt head. Maybe a lil less harsh on top but when they were cranked through an hot plate attenuator they were very close sound wise. If I have ever thought things were too fat with the 50 I just turned it down a hair. Always works. Plenty of gain and fully saturated if you want. I can't see why anyone would ever need more gain or overdrive.
SUPER Lead w/cap all the way JOHAN!!. Did I hear alittle Hendrix?. Strat sounds cleaner with cap NICE JOB!!! I use 1971 and a 1974 .Shure Mike's bottom right good for Epiphone Explorer burstbuckers..and my P-90S.!!!
Thanks for all the awesome content! I assume since this is 71 you have a 100k 4ohm NFB? Also what about V2 in the circuit does it have the 0.68 microfarad cap? Also does this have the 22pF PI coupling caps? Thanks again!
@formulajoe2. Hey Joe. I just saw your comment. I have already made a 1964 JTM45 and are going to insert a DPDT switch to toggle between shared and split cathode on V1. I will also include a 68 nF on V2a. The reason I made the decision is, the sound of JTM45 is basically a bass circuit. I also made the rectification switchable from GZ34 tube to solid state, mostly to ease the transition from standby to on. Best wishes for the build. Steffen
great video Johan... what is tour opinion about the reissue handwired plexis from Marshall?... and what do you think about installing a master volume on those kind of amps??
as johann said, great amps. The 1959HW sounds a bit "special", but the actual owner of the original amp (as far as i remember a model from 1968) says, that the reissue sounds 1:1 like his original. The biggest plus: It is handwired. You can very easily tweak it to your own taste without spending much money and it is always reversible. Putting in a PostPhaseInverterMasterVolume (=ppimv) is a huge benefit (just use one of the speaker outputs or anything else on the backside, I hate when the look of the frontpanel is destroyed). I have it in all my non-master Marshalls (and some laneys i modified to be a 1959/1987 :D ), it just sounds great. To my ears, it works better than Powebrakes/silencers etc. You can even play bedroom-level with a cranked 100W amp (of course it doesn´t sound like on a serious volume, but it kinda works). And its not that expensive to do. My workhorse is a 1979 SuperLead that has been slightly modified to late-60s specs... You can look it up in one of my videos (only have 3 :D ). Just recorded with an iphone, but you get the idea of what an amp like this can sound like on "normal" volumes.
I have a future video proposal for you Johan. When using the same guitar, amp and speakers. Can you emulate different speaker elements just by using an EQ pedal? Lets say for instance; can you make a green back sound like a vintage 30 by using an EQ pedal?
Love this stuff. Love the combination of electronics and how they influence the sound! A question if the Fender bassman 1959 is so simple, why can't they replicate it perfectly?
Components not the same, valve quality not as good, speakers probably not made any more. The circuits are EASY to build, but the parts them selves won't be the same as 60 odd years ago!
@@torarinvik4920 The components are available, but the methods and some materials used for producing them aren't the same. There's a level of variability from older pickups, transformers, and capacitors that we don't see as much with modern manufacturing practices. Formulas for speaker cone and glue materials have been lost to time, or chemicals outlawed for health reasons. We can recreate the amps, but they won't necessarily produce exactly the same sound. It'll be close perhaps
Great video, as always, Johan! Can you please give me an advice on Greenback cabs, I'm playing a reissue Super Lead 100W through 2x12 V30s cab at the moment and I'm looking to get a 4x12 Greenback cab but I'm not sure what power rating would be best in order not to blow them? I love the sound of 25 w Greenbacks because of the early breaking sound they give in comparison to V30s and they give me additional distortion so I don't have to additionally push it, but I'm worried they might blow so I'm considering getting higher wattage speakers (H30s or Creambacks). I'm not sure they'd give the same or similar result. I'm using Boss SuperOverdrive to push the amp and I rarely go over 3 in volume, even when I jump channels and I see a lot of people warning the output of the head will ruin the 4 25w greenbacks pretty soon. What would you do in my place, should I go to a tech and measure the output my head is outputting when I use it the way I so? Sorry for the lenghty text, Johan. Thank you very much!
It's a much more subtle difference than the bright cap, though I'd think it would be slightly more noticeable with a pedal hitting the input with a larger voltage. The split cathode resistor is a slightly colder bias, which should give you slightly less gain and more distortion.
The JCM800 and SLO100 use a 10k and 39k unbypassed resistor respectively for that awesome, asymmetric clipping full of beautiful harmonics. It makes the bias so cold that it's operating in a very non-linear region.
More great stuff love all your videos, I am by no means a good player, but I LOVE the guitar and the sounds of varying amps, guitars/pickups, and speakers.
Great demo, thanks, and pretty wild differences. Would it be possible to mod a superlead to superbass using a lead/bass switch, involving everything you described?
Hey johan, Great comparrison, Just for future reference (english tip for the day). There is no word "Splited", it's one of those words where its just "Split" for past and future / all circumstances. Hope I'm not being a D***K pointing out. Thought you might like to know :).
Robin Trower usually turns the Treble off and the Presence off on a Super Lead. The Vintage-Modern’s he uses now pretty much have same Treble & High’s off.
IF I RECALL CORRECTLY... Isn't there like a .068uf plate capacitor (1st stage) on the BASS amps, As compared to the .022uf on the guitar amps? That .068uf's extra capacitance definitely contributes to muddiness on 6 string guitars, at least at lower volumes. I've actually lowered several amps through the years to .01uf.
that feedback was insane,. high enough in pitch not to be too much of a nuisance though,. when would someone ever need that super cap bright sound, are there examples of people using this setup before you?
Most of all I feared for your Les Paul sitting above you there at the end of the video. It nearly fell over and hit you over the head at one point. That's bonkers to put it up there. I was more worried about the guitar than your skull sorry. I am glad you both survived that precarious prop setup. Lol. I think about setting my replica JMP 1987 model up for split cathode, so I can do a gain mod based on cascaded inputs. But currently I am really liking a plugin of a Silver Jube, so I dunno. It sounds like the no bright cap, shared cathode demo. Nothing I can do with pedals and EQ gets it into 2204 territory, let alone Silver Jube. It insists on sounding 1960s. A good thing sometimes, but not others. When I have an amp with a more modern sound suited to '80s shred tone I get frustrated I can not get an old school tone if I get back on a Jimmy Page thing etc. On the other hand, when I have the vintage sounding amp I get annoyed that I can not get the more modern tone with the tighter bass response etc. I end up resorting to plugin amps. Maybe I need two amps, or to heavily modify this one to do both sounds correctly. It's possible, but more techy than my current modding ability and Marshall amp modders in NZ are rarer than flying Kiwis. P.S. I compared the Amplitube 5 Red Pig JMP plugin model to my amp running thru a reactive load and IRs in DAW etc. It is so close that I do not bother using the amp. It is not exactly the same, but near enough that it makes risking the amp blowing up not worth it (1). However, what I can not get using a model is that interaction between the speakers and strings that causes the endless sustain due to feedback, e.g., Spinal Tap. That adds so much extra harmonic content and it is missing from all modellers (you can kind of get it by playing in front of a loud studio monitor though, but then I get noise complaints from the grumpy apartment dweller next door). Nothing beats being able to crank an amp thru a cab huh. 1). I watched the AC/DC rig rundown. More than once if I am honest. Angus blows up so many Plexi amps that he carries a lorry load of spares on tour. He also employs a full time tech to continually repair the blown ones. Brian May has a similar issue running the Vox AC-30s at full blast. Now I am very apprehensive to run my JMP replica on 10 through a load box, or even on 7. I blew up a 1959RR that way in the first week of owning it (running into a Palmer PDI-03). I am going to resort to a PPIMV to tame this 50 watter -- at least until I get so good at guitar that I can afford a massive rehearsal space at home, a full time tech and spares too -- I am 51 now and not in great health, so I had better get on with it :D. BTW. Speaking of Angus, there is the Replica unit that is a boost and compander like in Angus' old wireless unit. Angus uses one now too. But I doubt it is the key to his sound like people are saying. That's because he did not have that old wireless for decades, or the Replica. But he still sounded the same. I am currently thinking about his pups. I swapped a 498T for a Whole Lotta Humbucker. The WLH sounds really nice, but the 498T sounded so much more like Angus. It makes me think his pups were not PAF-ish, but were rewound hot etc. Who knows for sure? For now, I just go with what works, plus I think a lot of his tone simply comes from the fact that he gives it heaps (giving it heaps in NZ kind of means lots of gusto or something).
Somehow I have missed this video 4 years ago. Still I need to comment although no one will read it probably 😊. First let’s mention what is the function of the cathode resistor. It biases the triode. Let’s address why they use common cathode resistor and the bypass cap. Reason no. 1 it simplifies the layout by reducing number of parts. Second reason is that it costs less. Leo Fender was a genius but he saved wherever he could. Now this picture worries me. If you are not changing the triode biassing there should be a perceivable difference in the tone. Hence just splitting cathode circuits shouldn’t change the tone much. Mind you that in 4 input and jumped inputs situation things get a bit more complex. Here I am talking about two triodes completely in separate circuit parts and not jumped channels. Standard Fender layout is 1.5K resistor and 25 uF cap per triode. When two cathodes are using same biassing circuit then values should theoretically change to 750 Ohm and 50 uF. But 750 Ohm was not popular value so available 820 Ohms was used. Sometimes 25 uF cap would be used. Well less capacity in bypass is less gain per stage but if you can use just one triode at the time does it really matter? It does if you use both when in jumped channels though. Though point here is that if you want to split them you have to double the resistance and eventually use half of the capacitance. Leaving same values of the resistors and splitting them will double the bias current. In the preamp tubes this is not directly catastrophic even. Those do not draw tons of current and do not red plate as easy as the output tubes. Still you are putting the tubes out of the specs. It changes the tone while tube bias is way to hot for the tubes. It reduces the life expectancy as well. Once again preamp tubes last longer than the output tubes hence lifetime reduction is not that drastic as with the output tubes. In early Marshall amplifiers you find 820 Ohm but bypassed with 250 or 330 uF. So when splitting them use 1.5 K Ohm resistors to maintain the biassing. One more measure implemented to save money and simplify the layout was use of the boule capacitors. Mostly 2x25 uF 25V in the cathode biassing of the preamp tubes in Fender amplifiers. In some cases I really do not fault them for that. Imagine amplifiers with tube harmonic tremolos that use 3 tubes for it or better said 5 triodes for the tremolo only. Lots of bypassing was needed. One double cap could do two to theoretically 4 triodes reducing the clutter. What is negative about using same biassing for two triodes? Well you could say that there will be some crosstalk interferences. Is that so bad in this type of circuit where you are jumping channels and have mono signal anyways? So not really a big difference. I personally like to overbuild and use what’s “needed” to ensure quality. So in my designs I use dedicated biassing for each triode. Anyhow regarding statement that more bypass capacitance makes more gain it is just applicable with the same cathode resistor value. In later stages you see 2.7 KOhm and 1uF combination and in those circuits you have often more gain than in 1.5 KOhm and 25uF combination. So statement is true that no bypass cap will make least gain, and by 1,5 KOhm resistor less than 25uF will make less gain than 25uF value. Often small Fender amplifiers haven’t used bypass caps at all. Adding them gives them more gain. Often I find myself adding various grid stoppers, adding bypass caps, adding choke and changing cathode resistor value on cathode biased output tubes on old amplifiers. Changing all caps is often needed as well. Checking resistor values and cleaning pots, jacks and switches is needed as well. There are some repair man that do only full recap and retube and do that to all amplifiers. Solves 95 percent of the issues. Carpet bombing. As the old amplifiers are not getting any younger and more and more capacitors die (even the coupling caps start to leak voltage) full recap does make sense. I mean if you find electrolytic caps leaking or dry out change them all. Or you will get back amplifier soon back. Same with the coupling caps. If one leaks the DC voltage change them all. They will all fail soon enough. I often change nodal resistors as well. Tons of those die in old amplifiers.
@@JohanSegeborn Duane Allman favored the Bass plexi with a Y cable into both top jacks, instead of a jumper. That sounds very similar to the Lead model, but cleans up differently with the guitar's volume knob. With the Bass spec amp, I find you have to push the volume knobs much closer to 10 to get a saturated lead guitar tone. But it gets such a warm, round tone when you roll back the guitar volume.
I wish this had been done with a Les Paul. I just can't ever seem to get into the tone of a Strat with any amount of overdrive. It's annoying or worse. Not a singlecoil pickup fan...unless we're talking about P90s.
Oh boy this is a dark teritory you are going through....I would like to hear different coupling capacitor types (paper in oil vs ceramic or metal film) in a superlead!just saying...😇
I’m really digging these “How the ... influences your amp” videos! Keep up the great work Johan.
Thanks Sam! I’m glad to hear that!
Same here! Love to hear the Tone Meister dissect what goes into the great tones we hear. Keep it up 👍😎🎸
This is so incredibly helpful for people considering amp mods, or amp tweaker nerds like me :) Have a great weekend!!
Glad to hear it. You have a great one too Andy!
First bright cap difference and now this, how much more awesome can this channel get? Its a jungle out there... My head spins and get stuffed with all different forum opinions. But here you can listen yourself and then decide what fits you, and I dont need to spend €2000 to find out.
Priceless! Thanks!
*edit*
I must say ... I was at your friends place, Ragnar, about 9 month ago and bought his 1968 cab, with pre-rola greenbacks from 69. The basscones 55hz. I restored it from that awful pink color, haha... Looks like new now. But what a good guy he was! Super friendly and nice. And I love the cab! Its your fault I got addicted to the pre-rola sound by the way... ;)
Thanks man, I’m glad to hear that! Ragnar is indeed a great guy and he’s taught me a lot about tone!
What I like the most about this amazing channel is that it’s about making old things sound great. Not new. This is a sustainable channel.
I’ve always wondered what differences there was. Didn’t know it was something so small. Thank you!
Johan, Thanks very much for this split/shared cathode and the bright cap videos. I have particularly wanted to hear the the two cathode arrangements compared like this. You have done a great service to tone hunters everywhere. You videos are especially useful because they let us hear each tone side by side in immediate succession, instead of trying rewire things, then testing the tones. This video confirmed my own experiments: the differences between share/split cathode are much more minimal compared with the differences between various bright caps (and no bright caps). My own preference is for a Bass spec amp, but with shared cathode and switchable bright caps. If you use a Y-cable to input the guitar in both top jacks (instead of jumpering or just plugging into one input) there is much more treble in the tone, so for that setup bypassing the bright cap sounds best, Even with the volume cranked it makes a big difference to my ears and fingers to not have the cap.
you are a service to humanity bro; thanks for all the info and incredible videos.
You re so nice to share your knowledge!! With precision and an infinite clarity.
Many thancks
Keep it going! Amazing how something so small genuinely influences the tone...
Cheers Patrik
" You know Me, I Love Both!"
Well done and thanks for sharing your efforts and insight! Be Well and have a great weekend Brother!
You have a great one too my friend!
Another great video, thanks for constantly adding informative and interesting content.
I don't get how you at the moment "only" have 65k subscribers, it should have been at least 650k.
Thanks Jan! Great to hear that!
Great stuff! If you didn't care about modifying your vintage amp, you could somewhat easily make both changes selectable by wiring-in two switches.
Well, this was pretty dope...and your riffs just keep getting better. Keep it up, man.
Once again you prove to be a master. Exactly right pairing the les paul with the super lead and the strat with the super bass. Classic tones right there. As a mutual lover of the jmp2204 mv, a 77 to be exact, I'd love to see more of your tone adventures around that amp with different carbs, etc. The jmp2204 and 2203 were on most of the great albums of the late 70s thru early 80s.
I haven't been to your site in a while Johan, the fanboys were gettin' a little thick, but damn, the content is so good I just can't keep passing by! I hove not watched this whole video yet but I predict a couple of things: A stellar representation of what a Marshall really sounds like in the hands of a Marshall guru.I also predict as a rockheaded kid in the 70s and only ever cranked a tube amp to 10 as a starting point and then set the gain. I had a 60's tube Canadian GARNET BTO, a 6ca7 power section behemoth with ugly knobs (WTF?!?!?!?) that I pulled the shafts out of as being stupid and all I didn't realize had set screws (double WTF!?!?!?!?) so I had my brother rig it cranked balls out including pull boosts, and went on jammin with an amp with NO adjustment knobs anywhere, so it was cranked up and on fire, or off. And I used it for a couple years at least, until being stupid as I stated earlier, and also a rockhead playing in a heavy rock band , I blew a fuse and did what the experts and nerds (bah. what do those loooosers know, I'm a freakin rocker to the end, metal or die'etc) said never to do, but man, it was in the middle of a ripping rehearsal, I removed the fuse and covered it in cigarette foil. Don't EVER do that. Of course a spectacular failure of epic but devastating proportions happened and among maybe everything else the transformer lasted maybe a second. So it was onto a Fender Twin, and then the usual suspects of the day, Ampeg V4, Hiwatt Custom 50 (YEAH!!!), Marshall Lead 50, Laney AOR 100, Lee Jackson M1000 Metaltronix, Bogner Alchemist, and the latest, Friedman Smallbox 50 , and the common denominator up until I got the Friedman is that the master might as well as been welded to 10.This windy last section of a gargantuan post leads me to the prediction of what I will choose from your shootout as the king of Marshall classic rock tone will be: Split V1 cathode, and that pesky bright cap won't make much different cranked up, but if it does, cap gone . Finito. Cranked Super Lead with a great player with great taste and great ears and a 50's style Les Paul will equal ROCK AND ROLL SPLENDOR!!! Now to watch and see if I am correct, or maybe just a complete ASS and watch this thing. Let the GAAAAAMES BEGIN!!
Always something cool and different can be expected from your videos and I always look forward to seeing what's next, thanks.
Cool man. Relevant to my work on a 5e3 this morning.
Awesome stuff ! Thanks for the vid and the break down , definitely going to clip my bright cap on the 68; plexi circuit ! Thanks again Johan !
The interesting thing is that by adding a few switches to the control faceplate Marshall could have allowed their customers to control these parameters and select whatever sound they wanted. I wonder why Marshall didn’t choose to do that. Many fender amps have a bright switch on them.
Yeah, I think if they had more competition in high gain early on they would havevhad too
capitalism?? hahaha all its about the profits
All these videos are awesome as always, but... I'm really waiting for your original album full of kickass riffs!
Great Video. Love that kind of content. To me, the best would be to have a 1pole on-off-on switch to select between 2 bright cap values or none. Bright caps as you showed have such a big influence. This should be a default control on any amp in by opinion.
Thanks Joël! Yeah I definitely agree
Very cool video, Johan! I definitely enjoy these videos, and I am grateful to learn what these small wiring differences make to the overall sound of these amps from your videos! Great stuff!
This is important for people to understand the difference of terminology: what Johan is doing here is NOT a bright cap experimentation project. It is BIASING comparison. A bright cap is placing a small capacitance across a Vol pot so that it allows higher frequencies to "bypass" across the resistance (typically 1Meg) when it's turned down and there's a lot of resistance making the high freq unable to make it through to the next stages of the amp circuit. A BIASING capacitor works completely different. It allows frequencies to be amplified by the tube depending on it's value (keeping this explanation simple to understand). When the value is larger such as 25uF used by Fender it allows the tube to be "fully bypassed" which yields all frequencies to be amplified including the entire low end. Don't confuse a "bypass cap" with a "biasing cap". This is why Fender amps turned up past 5 on the dial begin to distort so much - amplifying the bass frequencies also and towards 10 become flabby and unusable/non-musical. When this capacitor is made much lower like the .68uF used by Marshall (not even 1uF) it only bypasses (amplifies) the higher end frequencies (called shelving affect). This allows you to turn the Vol fully up and since the bass isn't being amplified like the prior example - keeps the tone/guitar nice and tight yielding a more controlled useable gain through the Vol pot's settings.A couple of other considerations to know: as with everything there's always trade-offs. The Marshall biasing will not allow the tube to give full gain throughout all frequencies (this is obvious by the prior explanation) BUT when played loudly with controls up and the amp given more output power you don't need or want this anyway. But in lower Vol settings the amp will not exhibit the same gain as the Fender amps do all things considered. Another is when the BIASING cap is removed you hear a noticeable lowering of Treble response (and tube gain) since these frequencies are also not being amplified further. However - there is a more "smoothness" created without it. This is how amp designers "voice" an amp using multiple stages to have high gain with smoothness Vs it sounding too bright/brittle/fizzy etc. Lastly, when TWO stages share a cathode resistor and bypass cap as in the example and amp in this video - it is extremely important to know that since both stages share you need only 1/2 the resistance & double capacitance to accomplish the same tube operating point (aka BIAS) as would be needed for each one individually (without getting into the math & science behind it). Hope this helps you all a little bit?
Sad, that this comment gets a single thumbs up in 4 years, but "Johan plugging into a toaster" gets 20.
Thank you so much for this video. I love modding! I did a Marshall DSL15 once.
Would you consider doing a FAQ video so all of us fans could ask questions about you? I have 2 questions:
1. After all the amps that you have gotten to play, what is your favorite to Jan at home with?
2. Being from Sweden have you ever met Peter Svensson (from the cardigans)? He’s one of my favorite guitarists
Thanks! Really good to hear that.
1) the amp I’m using at home is an 83 Marshall JCM800 4010 with a 71 G12H30 55Hz Greenback in it.
2) I haven’t met Peter Svensson but I’m told he’s a Marshall connoisseur like we are.
Cheers Johan
Thanks Johan, great comparison. Now, it would be good if you can make a video comparing the influence of tube rectified vs solid state rectified, in the sound of an amp, or if it doesnt matter to affect the tone.
Thanks Rafael! Thats a great idea! Will definitely do that!
@@JohanSegeborn Thanks Johan!
Yes! Make sure it is with an AC30 though!
@@royglennie
Agreed, the AC-30 would be the best for the experiment. Or even an AC-15.
@@rafaelpretto292 yes either would be good! I'm set on getting an AC30 so these would be useful!
Great idea Johan, and great making as usual !
Thanks Sylvain! Great to hear that
To those that love to tinker and build guitar amps, I think adding a bright cap is one of the easiest mods you can do to get a little more power and sizzle.
Great video, as usual, but it takes a brave man to put a Les Paul in such a precarious position ;)
I like both and to have them all on lil switches would be nice. I noticed that with split cathode and no bright cap sounded pretty good. Maybe the best of all of them to my ears. I usually set my bass all the way off or very low on my 1969 50 watt smallbox 86 (bass) circuit. I also turn up the presence pretty high around 8. I also owned a 71 super lead and would do A/B comparisons like this. They sounded very very close with the biggest difference to the feel. The super lead was stiffer and tighter while the 50 watt 86 circuit was more organic sounding and spongier. I could feel the 50 react more while I played it. I always asked others around me which sounded better and they always chose the 50 watt head. Maybe a lil less harsh on top but when they were cranked through an hot plate attenuator they were very close sound wise. If I have ever thought things were too fat with the 50 I just turned it down a hair. Always works. Plenty of gain and fully saturated if you want. I can't see why anyone would ever need more gain or overdrive.
thats great! the only thing i would have liked to hear is without the split cathode BUT WITH the bright cap
The riffs and licks are getting very tasty lately!
SUPER Lead w/cap all the way JOHAN!!. Did I hear alittle Hendrix?. Strat sounds cleaner with cap NICE JOB!!! I use 1971 and a 1974 .Shure Mike's bottom right good for Epiphone Explorer burstbuckers..and my P-90S.!!!
Thanks Robbie!
Thanks for all the awesome content! I assume since this is 71 you have a 100k 4ohm NFB?
Also what about V2 in the circuit does it have the 0.68 microfarad cap?
Also does this have the 22pF PI coupling caps? Thanks again!
I am building a JTM45 right now and was considering a split/shared cathode switch. I might just leave it alone now (shared).
@formulajoe2. Hey Joe. I just saw your comment. I have already made a 1964 JTM45 and are going to insert a DPDT switch to toggle between shared and split cathode on V1. I will also include a 68 nF on V2a. The reason I made the decision is, the sound of JTM45 is basically a bass circuit.
I also made the rectification switchable from GZ34 tube to solid state, mostly to ease the transition from standby to on. Best wishes for the build. Steffen
Hello Marshall! You should make and release, at least, a Super Lead Joham Segeborn Signature Amp!
Yeah, and dont forget the Cabinet with Celestion Greenback Pulsonic speakers (those should be re-issued too).
Hahaha! Thanks man. A Johan Segeborn signature model would be a 1977 2204 Reissue and it would omit my name in all marketing.
heroes and their catchphrases:
Hulk: HULK SMASH!!!
Captain America: Avengers, assemble!
All might: Now i'm here!
Johan Segeborn: Hi.
Hahaha
"Let's go".
"Cheers"
Wouldn't mind hearing one with shared cathode and bright cap still on
great video Johan... what is tour opinion about the reissue handwired plexis from Marshall?... and what do you think about installing a master volume on those kind of amps??
Thanks! They are great. I’ve had a 1959HW and ac1974X and I loved them. The speakers needs to be changed for vintage Celestions though
as johann said, great amps. The 1959HW sounds a bit "special", but the actual owner of the original amp (as far as i remember a model from 1968) says, that the reissue sounds 1:1 like his original. The biggest plus: It is handwired. You can very easily tweak it to your own taste without spending much money and it is always reversible.
Putting in a PostPhaseInverterMasterVolume (=ppimv) is a huge benefit (just use one of the speaker outputs or anything else on the backside, I hate when the look of the frontpanel is destroyed). I have it in all my non-master Marshalls (and some laneys i modified to be a 1959/1987 :D ), it just sounds great. To my ears, it works better than Powebrakes/silencers etc.
You can even play bedroom-level with a cranked 100W amp (of course it doesn´t sound like on a serious volume, but it kinda works). And its not that expensive to do.
My workhorse is a 1979 SuperLead that has been slightly modified to late-60s specs... You can look it up in one of my videos (only have 3 :D ). Just recorded with an iphone, but you get the idea of what an amp like this can sound like on "normal" volumes.
I have a future video proposal for you Johan. When using the same guitar, amp and speakers. Can you emulate different speaker elements just by using an EQ pedal? Lets say for instance; can you make a green back sound like a vintage 30 by using an EQ pedal?
Good idea for another video. +1
That’s a great Idea indeed!
Great idea.... Except the other way around. Can an EQ in the FX loop make a v30 sound like a Greenback?
I'm only using halfstack 4x12-s and 100 watt 2x12s now..greenbacks
Love this stuff. Love the combination of electronics and how they influence the sound! A question if the Fender bassman 1959 is so simple, why can't they replicate it perfectly?
Components not the same, valve quality not as good, speakers probably not made any more. The circuits are EASY to build, but the parts them selves won't be the same as 60 odd years ago!
Thanks! As DMS suggested the speakers are really difficult to replicate. And the output transformers.
@@JohanSegeborn Are the components not made anymore?
@@torarinvik4920 The components are available, but the methods and some materials used for producing them aren't the same. There's a level of variability from older pickups, transformers, and capacitors that we don't see as much with modern manufacturing practices. Formulas for speaker cone and glue materials have been lost to time, or chemicals outlawed for health reasons. We can recreate the amps, but they won't necessarily produce exactly the same sound. It'll be close perhaps
@@Andy_Yates True!
I miss my 1970 Superbass!!!! WHAAAAAHH!!!
:-)
Great video, as always, Johan! Can you please give me an advice on Greenback cabs, I'm playing a reissue Super Lead 100W through 2x12 V30s cab at the moment and I'm looking to get a 4x12 Greenback cab but I'm not sure what power rating would be best in order not to blow them? I love the sound of 25 w Greenbacks because of the early breaking sound they give in comparison to V30s and they give me additional distortion so I don't have to additionally push it, but I'm worried they might blow so I'm considering getting higher wattage speakers (H30s or Creambacks). I'm not sure they'd give the same or similar result. I'm using Boss SuperOverdrive to push the amp and I rarely go over 3 in volume, even when I jump channels and I see a lot of people warning the output of the head will ruin the 4 25w greenbacks pretty soon. What would you do in my place, should I go to a tech and measure the output my head is outputting when I use it the way I so? Sorry for the lenghty text, Johan. Thank you very much!
It's a much more subtle difference than the bright cap, though I'd think it would be slightly more noticeable with a pedal hitting the input with a larger voltage. The split cathode resistor is a slightly colder bias, which should give you slightly less gain and more distortion.
The JCM800 and SLO100 use a 10k and 39k unbypassed resistor respectively for that awesome, asymmetric clipping full of beautiful harmonics. It makes the bias so cold that it's operating in a very non-linear region.
More great stuff love all your videos, I am by no means a good player, but I LOVE the guitar and the sounds of varying amps, guitars/pickups, and speakers.
Great demo, thanks, and pretty wild differences. Would it be possible to mod a superlead to superbass using a lead/bass switch, involving everything you described?
Hey johan, Great comparrison, Just for future reference (english tip for the day). There is no word "Splited", it's one of those words where its just "Split" for past and future / all circumstances. Hope I'm not being a D***K pointing out. Thought you might like to know :).
Robin Trower usually turns the Treble off and the Presence off on a Super Lead. The Vintage-Modern’s he uses now pretty much have same Treble & High’s off.
LPCustom3 I didn’t know that about Trower, but wouldn’t be surprised if it were true. Treble and presence on a SL will slice your head off.
Charles Livingston I work on his amp here in the States
Marshall works on his stuff in the UK
Oh Coarse SL without B Cap, with split Cath. Is it.
Wow!
IF I RECALL CORRECTLY...
Isn't there like a .068uf plate capacitor (1st stage) on the BASS amps, As compared to the .022uf on the guitar amps? That .068uf's extra capacitance definitely contributes to muddiness on 6 string guitars, at least at lower volumes. I've actually lowered several amps through the years to .01uf.
Johan, vad är det för Les Paul som syns i introt?
Det är min 2008 R9a :-)
just put a split/share switch on the back as well as a bypass switch on the second stage. best of both worlds.
that feedback was insane,. high enough in pitch not to be too much of a nuisance though,. when would someone ever need that super cap bright sound, are there examples of people using this setup before you?
Most of all I feared for your Les Paul sitting above you there at the end of the video. It nearly fell over and hit you over the head at one point. That's bonkers to put it up there. I was more worried about the guitar than your skull sorry. I am glad you both survived that precarious prop setup. Lol.
I think about setting my replica JMP 1987 model up for split cathode, so I can do a gain mod based on cascaded inputs. But currently I am really liking a plugin of a Silver Jube, so I dunno. It sounds like the no bright cap, shared cathode demo. Nothing I can do with pedals and EQ gets it into 2204 territory, let alone Silver Jube. It insists on sounding 1960s. A good thing sometimes, but not others.
When I have an amp with a more modern sound suited to '80s shred tone I get frustrated I can not get an old school tone if I get back on a Jimmy Page thing etc. On the other hand, when I have the vintage sounding amp I get annoyed that I can not get the more modern tone with the tighter bass response etc. I end up resorting to plugin amps. Maybe I need two amps, or to heavily modify this one to do both sounds correctly. It's possible, but more techy than my current modding ability and Marshall amp modders in NZ are rarer than flying Kiwis.
P.S. I compared the Amplitube 5 Red Pig JMP plugin model to my amp running thru a reactive load and IRs in DAW etc. It is so close that I do not bother using the amp. It is not exactly the same, but near enough that it makes risking the amp blowing up not worth it (1). However, what I can not get using a model is that interaction between the speakers and strings that causes the endless sustain due to feedback, e.g., Spinal Tap. That adds so much extra harmonic content and it is missing from all modellers (you can kind of get it by playing in front of a loud studio monitor though, but then I get noise complaints from the grumpy apartment dweller next door). Nothing beats being able to crank an amp thru a cab huh.
1). I watched the AC/DC rig rundown. More than once if I am honest. Angus blows up so many Plexi amps that he carries a lorry load of spares on tour. He also employs a full time tech to continually repair the blown ones. Brian May has a similar issue running the Vox AC-30s at full blast. Now I am very apprehensive to run my JMP replica on 10 through a load box, or even on 7. I blew up a 1959RR that way in the first week of owning it (running into a Palmer PDI-03). I am going to resort to a PPIMV to tame this 50 watter -- at least until I get so good at guitar that I can afford a massive rehearsal space at home, a full time tech and spares too -- I am 51 now and not in great health, so I had better get on with it :D.
BTW. Speaking of Angus, there is the Replica unit that is a boost and compander like in Angus' old wireless unit. Angus uses one now too. But I doubt it is the key to his sound like people are saying. That's because he did not have that old wireless for decades, or the Replica. But he still sounded the same. I am currently thinking about his pups. I swapped a 498T for a Whole Lotta Humbucker. The WLH sounds really nice, but the 498T sounded so much more like Angus. It makes me think his pups were not PAF-ish, but were rewound hot etc. Who knows for sure? For now, I just go with what works, plus I think a lot of his tone simply comes from the fact that he gives it heaps (giving it heaps in NZ kind of means lots of gusto or something).
Split w/o bright cap FTW. Surprised I like that better being a JCM800 fanboy.
Somehow I have missed this video 4 years ago. Still I need to comment although no one will read it probably 😊. First let’s mention what is the function of the cathode resistor. It biases the triode. Let’s address why they use common cathode resistor and the bypass cap. Reason no. 1 it simplifies the layout by reducing number of parts. Second reason is that it costs less. Leo Fender was a genius but he saved wherever he could.
Now this picture worries me. If you are not changing the triode biassing there should be a perceivable difference in the tone. Hence just splitting cathode circuits shouldn’t change the tone much. Mind you that in 4 input and jumped inputs situation things get a bit more complex. Here I am talking about two triodes completely in separate circuit parts and not jumped channels.
Standard Fender layout is 1.5K resistor and 25 uF cap per triode. When two cathodes are using same biassing circuit then values should theoretically change to 750 Ohm and 50 uF. But 750 Ohm was not popular value so available 820 Ohms was used. Sometimes 25 uF cap would be used. Well less capacity in bypass is less gain per stage but if you can use just one triode at the time does it really matter? It does if you use both when in jumped channels though.
Though point here is that if you want to split them you have to double the resistance and eventually use half of the capacitance. Leaving same values of the resistors and splitting them will double the bias current. In the preamp tubes this is not directly catastrophic even. Those do not draw tons of current and do not red plate as easy as the output tubes. Still you are putting the tubes out of the specs. It changes the tone while tube bias is way to hot for the tubes. It reduces the life expectancy as well. Once again preamp tubes last longer than the output tubes hence lifetime reduction is not that drastic as with the output tubes.
In early Marshall amplifiers you find 820 Ohm but bypassed with 250 or 330 uF. So when splitting them use 1.5 K Ohm resistors to maintain the biassing.
One more measure implemented to save money and simplify the layout was use of the boule capacitors. Mostly 2x25 uF 25V in the cathode biassing of the preamp tubes in Fender amplifiers.
In some cases I really do not fault them for that. Imagine amplifiers with tube harmonic tremolos that use 3 tubes for it or better said 5 triodes for the tremolo only. Lots of bypassing was needed. One double cap could do two to theoretically 4 triodes reducing the clutter.
What is negative about using same biassing for two triodes? Well you could say that there will be some crosstalk interferences. Is that so bad in this type of circuit where you are jumping channels and have mono signal anyways? So not really a big difference.
I personally like to overbuild and use what’s “needed” to ensure quality. So in my designs I use dedicated biassing for each triode.
Anyhow regarding statement that more bypass capacitance makes more gain it is just applicable with the same cathode resistor value. In later stages you see 2.7 KOhm and 1uF combination and in those circuits you have often more gain than in 1.5 KOhm and 25uF combination. So statement is true that no bypass cap will make least gain, and by 1,5 KOhm resistor less than 25uF will make less gain than 25uF value.
Often small Fender amplifiers haven’t used bypass caps at all. Adding them gives them more gain.
Often I find myself adding various grid stoppers, adding bypass caps, adding choke and changing cathode resistor value on cathode biased output tubes on old amplifiers. Changing all caps is often needed as well. Checking resistor values and cleaning pots, jacks and switches is needed as well.
There are some repair man that do only full recap and retube and do that to all amplifiers. Solves 95 percent of the issues. Carpet bombing.
As the old amplifiers are not getting any younger and more and more capacitors die (even the coupling caps start to leak voltage) full recap does make sense. I mean if you find electrolytic caps leaking or dry out change them all. Or you will get back amplifier soon back. Same with the coupling caps. If one leaks the DC voltage change them all. They will all fail soon enough.
I often change nodal resistors as well. Tons of those die in old amplifiers.
hi, i have a 1973 50 watt Marshall, show me how to give it high gain and add a master volume.....thats what i want to see.
Get a JCM800/900 and keep the amp unmolested, use a pedal even; it wasn't what the amp is made for.
My favorite is without the bright cap
Now try this with jumpered channels! (insert evil mad scientist laughter)
Hahaha! ;-) yeah some suggest that bridgeing makes Super Bass obsolete, but for cleans and semi cleans I dont agree.
@@JohanSegeborn Duane Allman favored the Bass plexi with a Y cable into both top jacks, instead of a jumper. That sounds very similar to the Lead model, but cleans up differently with the guitar's volume knob. With the Bass spec amp, I find you have to push the volume knobs much closer to 10 to get a saturated lead guitar tone. But it gets such a warm, round tone when you roll back the guitar volume.
I wish this had been done with a Les Paul. I just can't ever seem to get into the tone of a Strat with any amount of overdrive. It's annoying or worse. Not a singlecoil pickup fan...unless we're talking about P90s.
Video is uploaded 27 second ago but comments are from 40 minutes ago
Oh My UA-cam
LOL! It was premiered 16 mins ago!
@@DMSProduktions I think its about where do we live :D
That's because you have entered " The Johan Zone" a place where space and time don't exist, only tone......serious fucking tone!!
@@evrenyilmaz4864 It shouldn't matter!
@@leftyfusion88 Absolutely! \m/
Oh boy this is a dark teritory you are going through....I would like to hear different coupling capacitor types (paper in oil vs ceramic or metal film) in a superlead!just saying...😇
Superbass, cut the bright cap and separate the VI cathode. If you want extra treble I would roll with JBLs or Altec Lansing speakers.
I'll take the split cathodes and no bright cap.
I am vaitink forr dis wan! \m/
\m/
you also need to correct for plate voltage and bias voltage between amps to make a fair comparison. otherwise its not very scientific.