New marshall studio vintage came with 4700pf, it was too bright. I added a switch with a 100pf ,50pf and no cap. I play at low volumes so most of the time I play with no cap at all
Thank you for a great demo! I just picked up a mint Carvin Legacy and a 1000pF bright cap on the overdrive channel volume pot took care of the overly dark voicing this amp can exhibit. Such a simple mod with huge scope for tone sculpting!
Well done! I think a higher value bright cap might sound better for an earlier, pre-1970, Super Lead when they were generally darker than the later years.
Crank a 4 holer up over 7 like you’re supposed to and it doesn’t really matter what cap is in it. My 67 1986 is modded with a 200pf cap but it’s cranked to 7. My 71 1987 has the 4700 cap but with the amp on 8 it’s not having much effect and is only a little brighter/tighter than the Plexi, just abit gainier. Both amps still clean up beautifully. Absolutely no compromises on the clean sounds and it’s like having the best of both worlds. This is all straight into the top left input, no jumping channels. Nobody jumped channels back in the day because they all cranked the amp and used the guitars controls for their sounds.
Awesome demonstration and explanation of the different bright caps! To me it would make most sense for amps like this to offer a few options with a off-1000pF-2200pF type 3-way switch. I know some amps have this but most just have an on/off type two-way switch at best which often results in it being either too dull or too bright.
In my own Marshallesque builds I put in a small three position switch for this. But I don't want to drill the amp out. If the owner wants I can put in a CTS push-pull for the volume, though it's a $20 pot. But he's in CA and I'm letting him sleep in.
@@PsionicAudio Wow that's some differences. I learned I may want a bright cap switch of some kind on my 69 smallbox which is the 1986 bass circuit. At first I thought oh it sounds best without a bright cap but as I listened I heard what sounded like a gain increase as more mids pass through. This could be useful on my amp. Only problem is I might want all of them. It's hard to figure out what I like best from this video because I'm sure every amp acts differently from each cap. So would be best to hear each on my actual amp as it's being decided. Hmm a way to do it without drilling a hole? Is this the biggest difference between lead and bass specs? Sounds like it could be.
There are a lot of other differences, but this is the one that really stands out to most players. You can have a tech temp in a switch to try different bright caps, no bright cap, etc, so long as the volume pot solder joints aren't factory red (or if you don't care about that). If you want to switch, the only good way is a push-pull volume pot, but that messes up the factory buss wiring. So it depends on if your '69 is a "player" or is in original condition. In which case don't change it. This video started out as a full listing of the differences between JMT-100, Bass, Lead, Super Bass, Super Leads, etc, from '67 to '70. But it was getting huge and sprawling and disorganized so I trimmed it to just the bright cap comparisons. But I'll redo the full Marshall circuit history video at some point, hopefully soon. It's just... a lot.
@@PsionicAudio oh that would be great. Can't wait for that one. I watched something where it showed the differences between split cathode and shared but I didn't hear much difference with that one if I remember correctly. Maybe a little bit but not as much as this bright cap difference.
Great to see a comparison like this. Over the years I’ve come to accept that for myself I need a different amplifier for each volume level or style of playing. My amplifiers are all set up to my liking at 70% volume or higher. I’ve never had good luck trying to get an amplifier to sound acceptable at both loud and low volume levels.
great demo. personally, I think anything above 500pf is past the point of dimishing returns. I've had old Traynor amps that used 1000pf caps, and they sounded good with dark-ish pickups, but there wasn't a lot of range in the tonal respose. excellent e-splanation of the benefits of jumpering normal and bright inputs!
Anything from 500pf to 1000pf either doesn't filter enough highs or lets in too few mids. Above 100pf you get some mids back which balance by softening the added treble pass thru
250pf and no more. Just the right amount of chime and no harshness. Everything above that, especially 500pf and 1000pf are just painful!!!! I think that with a lot of gain there is so much compression going on that the brightness is tamed a bit (though I can definitely still hear it).
I am finding this video very useful as I have a prospective customer with a pig nose g40v that he’s complaining about it being to bassy. So I am looking at the schematic, it has a 220 uF bypass cap like on the first stage of a fender bassman which it’s supposedly cloned after but has the 2k7 bias resistor of the lead channel of a plexi. And to add insult to injury only has a 47 pF bypass capacitor on the pot! I am thinking if anything it could use that 5,000 pF bypass capacitor! But probably going to just drop that cathode capacitor way down.
Listening on my laptop speakers I think gave me a good idea of the differences . My preference was 250p , maybe 500p . or somewhere in between those . I have a 76' 1987 on the bench at the moment for a new choke and OP transformer , plus the filter caps , bias circuit etc . so will run the same experiment .Cheers
Oh my God 4700pf sounded like heaven. It seemed the higher the Pico farrads the sweeter it sounded to me. But then again I have a unmodded 1975 MKII 50w lead So I am used to the bright cap being in there.
Hey Lyle, I hope you or someone reading this in the comment section can help me with this: I have a JTM45 reissue from Marshall that I picked up at an estate sale. It’s a great amp, but I’ve always thought it to be too bassy- I run the bass at zero. I opened it up today and found that there is no bright cap on the amp. If I’m looking for a tighter bass, would placing a cap in there be my answer? I use the amp for clean / edge of breakup tones and use some pedals. I really like what I’ve felt when playing the SV20 which I assume has a high value bright cap in it. If I can get the JTM45 closer to that feel and response I would be thrilled. I thought that the original cap value would be 470pf, but am not certain. If I added a cap I would want to go stock / period correct - possibly a push-pull pot to engage or remove it on the bright channel. Thanks so much for your time and any help! Nick
Bright caps to me are more for 24.75 scale length, mahogany dark type guitar sound. 25.5 fender scale w/ bright caps is an tough place to dial in the sound.
Listening on a mobile phone speaker (which is more revealing than you may think, if you know what you're listening out for!) - my personal preference would be either the 250 or 500 as a trade off between low and high volumes. Other opinions are available! Great, great sounding amp, with the wiring inside as a work of art.
To my ear and speaker on my computer, it is the 250 pf cap. If you give the customer too much, it can be too bright and too many mids. If you offer 2 different caps, then 250/1000 pf. That's my opinion Lyle. Cheers
I put a push pull on my Plexi ..pushed with original value and Pulled with a 100pf ... for clean tones the 100 is heaven. No cap is just too dull for my taste.
Update: I went with 4700pf…. i notice that 4700pf brings in more mids even at low volume… anything below 2200pf, all I hear was treble, and not a pleasant one,,,
An easy pedal compromise, is choose the caps you like with the gain up. Then instead of turning down the gain for clean playing- use an active volume pedal to turn down the volume. You get the same frequencies passing through at the volume you prefer. Or have a bypass looper pedal and put a bunch of guitar cord in the loop when you want to take out some of the highs
I like the idea of a variable bright cap but I question the aesthetics of the cardboard faceplate...sorry, just a bit of levity...didn't mean to waste your time.
@@PsionicAudio thanks for the info! Is the Layoutout similar or you changed a lot? I know you made some grounding changes. Great channel! Greetings from Uruguay.
¡Hola! Y gracias. The board layout is the same except I rotated the bias trim pot for easier adjustment. Oh, and I laid out the diode bridge in the rectifier differently.
250pf sounds nice, 100pf and even lower is enough. Its not about finding the tone, its about helping the circuit doing its best so everything above 250pf is not a guitar amps main idea IMHO.
I’ve been waiting for a video demonstrating the various bright caps so thank you! Surprisingly I actually like the no cap tone.
Awesome vid! I'm getting read to have a 3-way mini switch put on my SL for no cap, 100, and 4700. Thanks for sharing!
Could you show how you wired this? I’d love to have a three way switchable bright cap with a mini toggle.
I like the 100pf. Works at low volume, no change at high volume.
New marshall studio vintage came with 4700pf, it was too bright. I added a switch with a 100pf ,50pf and no cap. I play at low volumes so most of the time I play with no cap at all
Those are good values for bright caps, i use 56pf, just enough for brightness spark without high middle clipping.
Thank you for a great demo! I just picked up a mint Carvin Legacy and a 1000pF bright cap on the overdrive channel volume pot took care of the overly dark voicing this amp can exhibit. Such a simple mod with huge scope for tone sculpting!
Well done! I think a higher value bright cap might sound better for an earlier, pre-1970, Super Lead when they were generally darker than the later years.
I've made this test myself, and i like the 220pf/470pf range!
Upon first listen, I would be torn between the 250pf and 500pf and definitely jumpering the channels. Interested in seeing what the owner picks.
Crank a 4 holer up over 7 like you’re supposed to and it doesn’t really matter what cap is in it. My 67 1986 is modded with a 200pf cap but it’s cranked to 7. My 71 1987 has the 4700 cap but with the amp on 8 it’s not having much effect and is only a little brighter/tighter than the Plexi, just abit gainier. Both amps still clean up beautifully. Absolutely no compromises on the clean sounds and it’s like having the best of both worlds.
This is all straight into the top left input, no jumping channels. Nobody jumped channels back in the day because they all cranked the amp and used the guitars controls for their sounds.
Awesome demonstration and explanation of the different bright caps! To me it would make most sense for amps like this to offer a few options with a off-1000pF-2200pF type 3-way switch. I know some amps have this but most just have an on/off type two-way switch at best which often results in it being either too dull or too bright.
In my own Marshallesque builds I put in a small three position switch for this. But I don't want to drill the amp out. If the owner wants I can put in a CTS push-pull for the volume, though it's a $20 pot. But he's in CA and I'm letting him sleep in.
@@PsionicAudio Wow that's some differences. I learned I may want a bright cap switch of some kind on my 69 smallbox which is the 1986 bass circuit. At first I thought oh it sounds best without a bright cap but as I listened I heard what sounded like a gain increase as more mids pass through. This could be useful on my amp. Only problem is I might want all of them. It's hard to figure out what I like best from this video because I'm sure every amp acts differently from each cap. So would be best to hear each on my actual amp as it's being decided. Hmm a way to do it without drilling a hole? Is this the biggest difference between lead and bass specs? Sounds like it could be.
There are a lot of other differences, but this is the one that really stands out to most players. You can have a tech temp in a switch to try different bright caps, no bright cap, etc, so long as the volume pot solder joints aren't factory red (or if you don't care about that). If you want to switch, the only good way is a push-pull volume pot, but that messes up the factory buss wiring. So it depends on if your '69 is a "player" or is in original condition. In which case don't change it.
This video started out as a full listing of the differences between JMT-100, Bass, Lead, Super Bass, Super Leads, etc, from '67 to '70. But it was getting huge and sprawling and disorganized so I trimmed it to just the bright cap comparisons. But I'll redo the full Marshall circuit history video at some point, hopefully soon. It's just... a lot.
@@PsionicAudio oh that would be great. Can't wait for that one. I watched something where it showed the differences between split cathode and shared but I didn't hear much difference with that one if I remember correctly. Maybe a little bit but not as much as this bright cap difference.
@@PsionicAudio That would be a great video with all the circuit history. Can you show us how to build this test box?
Great to see a comparison like this.
Over the years I’ve come to accept that for myself I need a different amplifier for each volume level or style of playing.
My amplifiers are all set up to my liking at 70% volume or higher.
I’ve never had good luck trying to get an amplifier to sound acceptable at both loud and low volume levels.
The 2:57 time mark sounds pretty good. 👍 (at the latter part)
great demo. personally, I think anything above 500pf is past the point of dimishing returns. I've had old Traynor amps that used 1000pf caps, and they sounded good with dark-ish pickups, but there wasn't a lot of range in the tonal respose. excellent e-splanation of the benefits of jumpering normal and bright inputs!
Anything from 500pf to 1000pf either doesn't filter enough highs or lets in too few mids. Above 100pf you get some mids back which balance by softening the added treble pass thru
250pf and no more. Just the right amount of chime and no harshness. Everything above that, especially 500pf and 1000pf are just painful!!!!
I think that with a lot of gain there is so much compression going on that the brightness is tamed a bit (though I can definitely still hear it).
Nice sounds and info on the various caps..Great to get to hear those differences live..Ed..uk..😀
i think that one of the lower values in conjunction with the presence control would get me anything i need.
I am finding this video very useful as I have a prospective customer with a pig nose g40v that he’s complaining about it being to bassy. So I am looking at the schematic, it has a 220 uF bypass cap like on the first stage of a fender bassman which it’s supposedly cloned after but has the 2k7 bias resistor of the lead channel of a plexi. And to add insult to injury only has a 47 pF bypass capacitor on the pot! I am thinking if anything it could use that 5,000 pF bypass capacitor! But probably going to just drop that cathode capacitor way down.
Can you reset the amp back to its original state? That would be nice... An original 76' Marshall is really great
Man, great comparison. Very helpful reference.
Which bright cap size did the owner choose?
Listening on my laptop speakers I think gave me a good idea of the differences . My preference was 250p , maybe 500p . or somewhere in between those . I have a 76' 1987 on the bench at the moment for a new choke and OP transformer , plus the filter caps , bias circuit etc . so will run the same experiment .Cheers
great video; for me and based upon the sound that is coming out of my speakers, it's 250pF all the way....!!
excellente et intéressante vidéo, exactement ce dont j'avais besoin pour mon Guyatone
Mercí.
I like dark sounds when distorted and bright sounds when playing clean, kind of what EJ does.
Oh my God 4700pf sounded like heaven. It seemed the higher the Pico farrads the sweeter it sounded to me. But then again I have a unmodded 1975 MKII 50w lead So I am used to the bright cap being in there.
hola, gran video, le puedo poner este mod a un marshall 5005 lead 12, saludos.
I had a 68 clone w/PPIMV with no bright cap… I tried both 250pf and 470pf… I went with 250pf
Hey Lyle, I hope you or someone reading this in the comment section can help me with this:
I have a JTM45 reissue from Marshall that I picked up at an estate sale. It’s a great amp, but I’ve always thought it to be too bassy- I run the bass at zero. I opened it up today and found that there is no bright cap on the amp.
If I’m looking for a tighter bass, would placing a cap in there be my answer? I use the amp for clean / edge of breakup tones and use some pedals. I really like what I’ve felt when playing the SV20 which I assume has a high value bright cap in it. If I can get the JTM45 closer to that feel and response I would be thrilled.
I thought that the original cap value would be 470pf, but am not certain. If I added a cap I would want to go stock / period correct - possibly a push-pull pot to engage or remove it on the bright channel.
Thanks so much for your time and any help!
Nick
Hey Nick, watch my two Germino videos for the answers you want.
Bright caps to me are more for 24.75 scale length, mahogany dark type guitar sound. 25.5 fender scale w/ bright caps is an tough place to dial in the sound.
Anything over 100pF is all ego. :) Thanks for the demo.
Great Video!
Great amp series!!!
Listening on a mobile phone speaker (which is more revealing than you may think, if you know what you're listening out for!) - my personal preference would be either the 250 or 500 as a trade off between low and high volumes. Other opinions are available! Great, great sounding amp, with the wiring inside as a work of art.
It's like mixing on little Auratones!
@@PsionicAudio Ha! Yes it is indeed - and why so many records from the seventies sound so good.
To my ear and speaker on my computer, it is the 250 pf cap. If you give the customer too much, it can be too bright and too many mids. If you offer 2 different caps, then 250/1000 pf. That's my opinion Lyle. Cheers
I put a push pull on my Plexi ..pushed with original value and Pulled with a 100pf ... for clean tones the 100 is heaven. No cap is just too dull for my taste.
great video... 4700pf for me!
Unusable
i like the 1st one
Can i put this mod to my Marshall Origin 50 head? I worry cut the wrong cap, lol
200pF for my single channel JTM45 style amp
Oddly enough i liked 500 pf and 4700 when you first started
Update: I went with 4700pf…. i notice that 4700pf brings in more mids even at low volume… anything below 2200pf, all I hear was treble, and not a pleasant one,,,
Great video. Also explains why so many Marshall players used tone boost pedals
An easy pedal compromise, is choose the caps you like with the gain up. Then instead of turning down the gain for clean playing- use an active volume pedal to turn down the volume. You get the same frequencies passing through at the volume you prefer. Or have a bypass looper pedal and put a bunch of guitar cord in the loop when you want to take out some of the highs
Yeah, the old EB as "channel changerx....
I like the idea of a variable bright cap but I question the aesthetics of the cardboard faceplate...sorry, just a bit of levity...didn't mean to waste your time.
Hello. Could some one please tell me which schematic corresponds to this amp? Thanks!
Aside from the bright cap TBD, the '70 Unicord Superlead Mk II.
@@PsionicAudio thanks for the info! Is the Layoutout similar or you changed a lot? I know you made some grounding changes. Great channel! Greetings from Uruguay.
¡Hola! Y gracias.
The board layout is the same except I rotated the bias trim pot for easier adjustment. Oh, and I laid out the diode bridge in the rectifier differently.
@@PsionicAudio thanks for your answer, I will look in Google for a layout.
some of these amps shipped with 5000p bright caps . evh's was
1:06 1:23
2:32 2:43
3:18 3:28
Owned many back then....they don't build em like this anymore...and we can't use them as they're too damn loud!!! 🤣🤣🎸🎸😳😳
On my crappy phone speaker, 250 or 500 sounded best. But I can see where the 1k could be useful too!
i got 1n-off-5n on 2203
4700 sound the most plexiglass like to me
Log pot?
Of course.
@@PsionicAudio :-)
2:09
2:15
2:25
2:43
Has somebody made the 'sounds a bit boxy' joke yet?.
✌ 🎸
IMHO, no more than 250pf. Too thin and ice-picky above that.
250pf sounds nice, 100pf and even lower is enough. Its not about finding the tone, its about helping the circuit doing its best so everything above 250pf is not a guitar amps main idea IMHO.
All I know is it has to have a bright cap of some sort. The tone is too dark otherwise. Cool video.