I’ve been watching and learning from your videos for a few years now. I watch, build, learn, rebuild, etc. Things that didn’t quite make sense at first now seem obvious. If you ever decide to host a few seminars, I’ll attend. You’re a fine tech as well as a fine instructor. Thanks.
You've taught me more about early Marshalls and how they should sound than a whole room fulla self styled professors. Wish I'd seen this a few months ago. Grazie. Molto bene.
Fantastic video. Technical and detailed but not confusing, respect for the builder and the owner (and the viewer, for that matter), and very informative. Thanks for the great and unique content!
Holy crap! Greg Germino survived the tornado test! Lol What a solid amp. Sweet video as always Lyle! Very cool when you work on these higher end custom amps.
Reminds me of Pete Traynor throwing his amplifier off a roof top and throwing it down a flight of stairs and the amp still works. Good build quality for sure.
Voicing an amp is as much an art as it is a science. Particularly for the choice of a bright cap on the volume control since the corner frequency and level of the shelf change with the rotation of the volume control. Fender amps with a bright switch are easier to evaluate the results because you can bring the cap in or out of the circuit with a slide of the switch. I agree with your choice of keeping the value at 120pF or lower. You already have pre-emphasis dipping into the midrange with the cap across the resistor in the mixing section. You might even go as low as 47pF for the bright cap to only add a little sparkle at roughly 8khz and up but that might be a bit too subtle.
Love Germino amps. Greg is one of the nicest guys on the planet as well. The only problem is figuring out which Germino I want. Most likely will buy one of his JTM45/100 amps. I find the 45/100 to sound more together than the 45 and I don't know why. With the later EL34 models I prefer the 50 watt units over the 100. I just use my ears. Lol I would want KT66 in my 45 or 45/100.
The shared 1K resistor for the screens was on some JTM45s. I have JTM50 that I built myself, I'm a fan of the 470K Mixer resistors and 100pF bright cap. Negative feedback is on the 8Ohm tap with a 27K resistor. My favourite amp for classic rock. I must admit I preferred that Classic 45 after you made it brighter.
They make a nice looking and sounding amp. I always wanted one of these or a JTM45 by Metropolis. Ended up getting a Siegmund Midnight Blues because it was such a good deal. Scratched my JTM45 itch.
You know, there are not a lot of tube guys like us left out there. You speak my language. I would love to talk with you in person with a schematic present. So few left that have a clue how tube circuits work.
A year and a half ago, I passed up one of these beautiful amps for 2000 canadian. I would normally regret that quite a bit. But what happened next was I built my first amp. Now I'm about to start my 8th. I wouldn't have started on this wonderful journey if I had dropped that 2k.
Was ordering parts from Greg at MojoTone LONG LONG ago....yes, great guy n friend... Greg was FIRST in line doing Boteek Marshalls! Velvet George followed...Jim@Omegaamps
I have a JCM 900 2500 that at low bedroom volume, my ES347, sounds terribly muddy, but when I crank it, It sounds absolutely Marvelous! My other guitars don't have that problem. I think this is why I sold off a 50 watt SLX just over 20 years ago.
I was wondering about that toasty-looking old carbon comp and why you'd left it. Was firing up a screenie and paint to stick an arrow on it and ask you, then you pointed it out. Shouldn't have worried.👍😁
I had both a jtm and a 50 watt plexi built by Reinhardt. The JTM wasn’t anywhere near as loud as the 50 watt, but was very sweet, and loved boost pedals out front. I’ll agree that the amps are two different animals.
Great channel. Watch it regularly. Great to see a Germino. I have a Roccaforte custom 30. When it needs TLC may bring it to you. Very impressed with your work. Thanks.
I have a 68 50 w plxi amp head that i have had for 40 years i never jumpered the chanells i just use input 1 of the bright chanell and an overdrive my amp never sounded so good as when i could still get german telefunken power tubes todays tubes are not so good and i have used them all o well good show mate cheers
I don't think it can be said enough, that the sound that people hear on records of a certain amp, isn't necessarily what that amp sounds like in person. The first thing most mix engineers will do with any Marshall type amp is to boost the top end by a significant amount at about 7-8khz, and roll off the low end. The history of the recorded electric guitar is mostly processed in the studio.
Re your comments on the movie. We're not all American! I was surrounded by JTM 45's. I remember my first wife being angry when we were looking for a house in London; by the owner of one having a full stack of a JTM 45/100 standing in the middle of the Dining Room - this was the true King of Guitar Amps - I was too busy talking to the owner of it (to be nameless) rather than discussing the rather nice house... Pete. PS Only just realized that it was like the "Monolith" in "2,001 A Space...."
My Germino super lead 100 didn’t have a bright cap in it when I got it I put one in. Nothing to dramatic. 500uf. But a Marshall without a bright cap is dull I also did some ever every so slight mods with a couple values. NFB and one bypass cap. That’s it. Greg switched out the power transformer for me, since the old one was a beast , around 515v on the plates if I remember correctly The mains filter caps were also 200uf and 200uf. I put 100uf and 100uf like a 12000 series.
Hello, I had a 50watt superlead (1970's) and it was so loud! I had to get a rat pedal for any overdrive, the normal sound was loud and clean. That amp in video is fantastic, if I had one I would'nt use pedals because the tone is perfect. By the way I used a VOX with 4 25watt Celestion Greenbacks and it was a monster so much so that the bass player ended up with it and I got a twin!
Thanks for the constant insight and entertainment Lyle! So how different from the stock Marshall JTM45 did this project end up being? I have a 2005 reissue that I assume has a similar value bright cap on it, but would love to do something to tame the bass a little bit on the bright channel, similar to this Germino.
This was pretty much changing it from an early to a mid-period JTM45. Spoiler : this amp is coming back in next week for more tweaks. The owner was happy with this but was intrigued when I said it could be tailored even more. He wants more "airiness" - I'm having him bring his cab/speakers too. I need all the pieces of the puzzle.
@@PsionicAudio you mentioned Alnico Blues to pair with this? My local tech suggested the same, or celestial G12h 30 anniversaries. I went with the anniversaries since I have an AC30 w/ the blues that I hope to try with it some day as well. My Marshall cab came with 2x greenbacks that I found too dark for the JTM45 personally. Excited for part 2!
This is a great vid Lyle. I’m way behind on your stuff. Been learning Barry Harris for guitar. I want this amp or one like it! Anyway from few vids back wanted to say… #embarrassmentfee gave me the giggles.
JTM45s are dark? Is there some kind of pedal that could, I dunno, theoretically "boost" the treble or something? Maybe there's even a whole boutiquey sub genre of pedals of that nature.
It is my understanding that most tone stacks in tube amps are not active, but actually passive, and that the tone pots only reduce the levels of each frequency they cover and that they are actually essentially out of circuit at full level settings. If that is true, I don't understand why techs often refer to halfway up as flat. No tube guitar amp is designed to be frequency flat like stereo amps because guitar pickups are not flat in their output, rather they tend to be very mid-frequency heavy. Can you explain your perspective on tone pot settings? It sounds like 50% as being flat is an arbitrary statement since most amp tone stacks (such as classic Fenders, Vox and Marshalls) are passive and are not actually flat at all. Please explain further because I cannot reconcile the differences.
@@PsionicAudio You might also discuss the fact that Fender intentionally boosted both treble and bass frequency in their tone stacks to make up for the mid-heavy output of guitar pickups, trying to generally flatten out the final output. Marshall did not compensate for this non-linearity of pickup output, thus resulting in the mid-heavy tones of Marshalls vs. the "scooped" midrange of Fenders. It could be argued that by starting with a basic eq of flat, Marshalls actually end up accentuating the mids based on the non-linear frequency response of typical pickup output.
I noticed this turret solder joints right away. They certainly look better now. Did you say that the way they looked when you opened it is period correct?
I had a Germino 55, and I felt the same way, for me it was muddy, dark sounding. More so at lower volumes. I place a Tim pedal in front of it and it was magic.
I know what with RUclips coloration and my fickle imagination BUT CRIPES, the V-1 swap?? I preferred the previous and slightly microphonic tube's sound and smoothness... What is wrong with me?! ...and thanx for yet another great vid, Lyle
Good ear, but I accidentally turned up the Treble while swapping tubes. The first tube I put in was microphonic and I thought I adjusted the volume to check how bad but I accidently turned up the Treble. So you are hearing more there than changing from TAD to Tung-Sol.
When I build my amps, although they are quiet and easy to access, my pot wires connect on top and look like a bird's nest. How are they connecting their's? IE, the pink wires. If connected under the board on the bottom of turrets, my challenge would be not being able to flip up the board due to both side being wired and immovable. Any insights are appreciated. Thanks!
I'm baffled by how techs can keep all those specs straight and how they affect sound. I've built and amp and a few pedals, but I daren't stray from the schematic 😂
the coupling caps are all oriented with the outer foils facing the tube side (wrong?) . some say this matters some say it doesn't but i find it peculiar they are all pointed this way
They are all correct but one IMO. Most have the foil to the side of B+ voltage. The 100nf on the left side of the tone stack would theoretically be better the other way as it is closer to ground on that side than it is to B+. The PI input cap can be done either way - there are arguments for each - but it really doesn’t matter much there.
@@PsionicAudio that's eye opening. i used to go through marking them (with headphones and alligator clips) but not anymore. does it really make a difference?
@@thomass8472 The 45 has a shared cathode in V1A-V1B. V1B cathode should have its own 2.7K resistor, and .68mf bypass cap. EVH had a 4.7nf bright cap. I would add a bright cap selector switch. The 45 has a 56K slop resistor in the tone stack. The EVH has 33K resistor in that position. The 45 doesn't have a cathode bypass cap on the second gain stage V2A to my understanding. The 68SL had a .68uf bypass cap there. I don't see any filtering between V1, and v2 B+ on the 45. The 68SL had a 50uf filter cap on each side with a 10K 1W resistor between, (usually a single split 3 lead cap 2 x 50uf). On the 45 that filtering is between the cathode follower, and PI. The 68 only has a 10K resistor there, sot the filter caps get moved between V1, and V2. These are the major differences.
@qua7771 Thank you for taking the time for the directions. I appreciate you and your knowledge. I'll get back to you asap when I have time for some questions once I get started. Unfortunately I'm not sure when. I have some outdoor projects that need to be finished before the cold weather arrives. Thank you again.
@@thomass8472 No problem. So you know, this is not Lyle. My name is Rob, and I have built a few of these, done quite a bit if modification, and am a former Navy avionics tech. I always like chatting gear in the guitar community. Good people usually. I'll most likely be able to recall these two circuits, as they are the ones I'm most familiar with. All you will need is a few small resistors, and a few capacitors. It's not a complicated process. The hardest part is probably getting your bench set up. Since you built the 45, you already have experience building. The conversion is not a major undertaking at all. I can also recommend a few minor mods that can get you the sound your looking for.
Granted, 5 minutes in...but I swear some people don't turn knobs because some hack told them "every amp sounds best with everything at noon." If it's dark at noon, um...wouldn't one turn the highs or presence up? Or perhaps move over to the brighter channel? Continuing...
Greg is very adamant to doing repairs, as to keep his amps under warranty and are as DESIGNED. Be aware of this if anyone owns one. If one researches the tone they are chasing and chat with Greg, and for me a JTM 45 was not the Marshall sound I have been chasing. His Lead 55LV is what the Doctor ordered. So if one needs a mod done. Go through Greg. This amp is built to the spec. In other words, call Greg if something isn't working to your liking. Letting local tech interject their ideas and alterations deviate from warranty. Lesson is: Call Greg before even thinking of calling a local tech. Unless you don't care about voiding warranty.
Day late n a $$ short, but a simple X line master X the GRIDS of driver tube( p2 p7) wil work better n sound better imho........................old school.....................
Owner "plays a Les Paul and likes the blues and classic rock." LOL. Sure he also works a white-collar job, had the amp shipped sight unseen because it was a TGP flavor-of-the-month, and can't play it above 1 because the kids are asleep upstairs. Sad to see amps like this wasted on people who don't know what they're getting and can't play them the way they're intended.
I’ve been watching and learning from your videos for a few years now. I watch, build, learn, rebuild, etc. Things that didn’t quite make sense at first now seem obvious. If you ever decide to host a few seminars, I’ll attend. You’re a fine tech as well as a fine instructor. Thanks.
Hallelujah! You've referred me to just the amp I've been looking for. Thank you.
Regrettably, they’re essentially unavailable. It is a very niche product. You can’t get a JTM45 reissue from Sweetwater, either.
Greg Germino builds the best Marshall clone amps.his components,build quality,knowledge is impeccable.I own 4 of them for a reason.
I only have one (LV55), but I absolutely love it!
Why 4?
Any input on lead 35 vs bass 35?
You've taught me more about early Marshalls and how they should sound than a whole room fulla self styled professors. Wish I'd seen this a few months ago. Grazie. Molto bene.
Fantastic video. Technical and detailed but not confusing, respect for the builder and the owner (and the viewer, for that matter), and very informative. Thanks for the great and unique content!
Holy crap! Greg Germino survived the tornado test! Lol What a solid amp. Sweet video as always Lyle! Very cool when you work on these higher end custom amps.
Reminds me of Pete Traynor throwing his amplifier off a roof top and throwing it down a flight of stairs and the amp still works. Good build quality for sure.
@@roncarter2188 I remember that one , the link is here below.
ruclips.net/video/QwHYulZPUoA/видео.html
That amp has some strikingly beautiful lead dress.
I really like it with the bright cap alteration.
Wow! This sounded great with the mods. Now I want o JTM45.
Voicing an amp is as much an art as it is a science. Particularly for the choice of a bright cap on the volume control since the corner frequency and level of the shelf change with the rotation of the volume control. Fender amps with a bright switch are easier to evaluate the results because you can bring the cap in or out of the circuit with a slide of the switch. I agree with your choice of keeping the value at 120pF or lower. You already have pre-emphasis dipping into the midrange with the cap across the resistor in the mixing section. You might even go as low as 47pF for the bright cap to only add a little sparkle at roughly 8khz and up but that might be a bit too subtle.
Love Germino amps. Greg is one of the nicest guys on the planet as well. The only problem is figuring out which Germino I want. Most likely will buy one of his JTM45/100 amps. I find the 45/100 to sound more together than the 45 and I don't know why. With the later EL34 models I prefer the 50 watt units over the 100. I just use my ears. Lol I would want KT66 in my 45 or 45/100.
love 45's!!! My fav Marshall of all time.
The shared 1K resistor for the screens was on some JTM45s.
I have JTM50 that I built myself, I'm a fan of the 470K Mixer resistors and 100pF bright cap. Negative feedback is on the 8Ohm tap with a 27K resistor. My favourite amp for classic rock. I must admit I preferred that Classic 45 after you made it brighter.
I cannot hear the difference a 100pf bright cap makes. I can hear 500pf and above. I think my hearing is okay. Maybe I should try a hearing test.
The JTM45 is a great platform for pedals, even for rock/hardrock/metal, it sounds great. Even the KT66 sounds great with a massive distortionpedal..
It can sound great for Ratt style tones with a tube screamer or sd-1 used as a boost
Charlie Starr uses this head, I don't because I can't afford one. Love your videos and your craftsmanship Lyle.
That amp sounds great It is mellower
That tone is what I need ! I’m a jcm800 fan own 3 of them this sounds awesome
Very Faces sounding
The jumpered tone at the end was really good. I was hoping you would bust into some "Fly by Night".
Build quality indeed looks great. Thanks for taking us for the ride.
Wow, that’s exactly the sound I’m looking for. Very nice.
They make a nice looking and sounding amp. I always wanted one of these or a JTM45 by Metropolis. Ended up getting a Siegmund Midnight Blues because it was such a good deal. Scratched my JTM45 itch.
You know, there are not a lot of tube guys like us left out there. You speak my language. I would love to talk with you in person with a schematic present. So few left that have a clue how tube circuits work.
Sir you sound like Michael Ironsides. Love Germino good video.
I don' t know anything about electronics but still I watch this like I watch a movie. Popcorn please !
A year and a half ago, I passed up one of these beautiful amps for 2000 canadian. I would normally regret that quite a bit. But what happened next was I built my first amp. Now I'm about to start my 8th. I wouldn't have started on this wonderful journey if I had dropped that 2k.
Great mod: sounds really the way it should ! 👍🏻
I remember you telling me about these amps on the phone when I asked about Marshall sounds. What a perfect sound!
love the tornado versus amp story. love your channel. Namaste
Was ordering parts from Greg at MojoTone LONG LONG ago....yes, great guy n friend... Greg was FIRST in line doing Boteek Marshalls! Velvet George followed...Jim@Omegaamps
I have a JCM 900 2500 that at low bedroom volume, my ES347, sounds terribly muddy, but when I crank it, It sounds absolutely Marvelous! My other guitars don't have that problem. I think this is why I sold off a 50 watt SLX just over 20 years ago.
Sounds perfect for hitting with a treble booster! It's no mystery why the Rangemaster was created.
I didn't even think of that.
Late to the comments, but WOW! To my ears that amp sounded wonderful!!!!!!
I was wondering about that toasty-looking old carbon comp and why you'd left it. Was firing up a screenie and paint to stick an arrow on it and ask you, then you pointed it out. Shouldn't have worried.👍😁
Another great sounding amp. Man you just gotta love valve amps nothing like them. Jim just got it right with the 45. Great clone.
13:37 “anyway … I famously digress”. Never stop digressing. You rock!
Cool video! The bright cap really matters for Marshall circuits. Without one it's lifeless. I love a 4k7 on my Ceriatone Plexi 50!
I had both a jtm and a 50 watt plexi built by Reinhardt. The JTM wasn’t anywhere near as loud as the 50 watt, but was very sweet, and loved boost pedals out front. I’ll agree that the amps are two different animals.
great video, and I am learning a lot, much appreciated
Great channel. Watch it regularly. Great to see a Germino. I have a Roccaforte custom 30. When it needs TLC may bring it to you. Very impressed with your work. Thanks.
I prefer the stock sound. This isn’t a knock on the work you did, I just think Greg got it right from the beginning.
Sounds so nice
You’re an artist, Lyle.
I have a 68 50 w plxi amp head that i have had for 40 years i never jumpered the chanells i just use input 1 of the bright chanell and an overdrive my amp never sounded so good as when i could still get german telefunken power tubes todays tubes are not so good and i have used them all o well good show mate cheers
I don't think it can be said enough, that the sound that people hear on records of a certain amp, isn't necessarily what that amp sounds like in person. The first thing most mix engineers will do with any Marshall type amp is to boost the top end by a significant amount at about 7-8khz, and roll off the low end. The history of the recorded electric guitar is mostly processed in the studio.
Beautiful amp!
I love this channel
Re your comments on the movie. We're not all American! I was surrounded by JTM 45's. I remember my first wife being angry when we were looking for a house in London; by the owner of one having a full stack of a JTM 45/100 standing in the middle of the Dining Room - this was the true King of Guitar Amps - I was too busy talking to the owner of it (to be nameless) rather than discussing the rather nice house... Pete.
PS Only just realized that it was like the "Monolith" in "2,001 A Space...."
My Germino super lead 100 didn’t have a bright cap in it when I got it
I put one in. Nothing to dramatic. 500uf. But a Marshall without a bright cap is dull
I also did some ever every so slight mods with a couple values. NFB and one bypass cap.
That’s it.
Greg switched out the power transformer for me, since the old one was a beast , around 515v on the plates if I remember correctly
The mains filter caps were also 200uf and 200uf. I put 100uf and 100uf like a 12000 series.
Good one Lyle...I really enjoyed it.
Hello, I had a 50watt superlead (1970's) and it was so loud! I had to get a rat pedal for any overdrive, the normal sound was loud and clean. That amp in video is fantastic, if I had one I would'nt use pedals because the tone is perfect. By the way I used a VOX with 4 25watt Celestion Greenbacks and it was a monster so much so that the bass player ended up with it and I got a twin!
NMV plexialikes are brutal.
Brutal is the word! Like this Germino though!
I thought that the amp sounds perfect when he first started playing! Need to get one for myself!
Hitting it with a treble booster should tighten the lows and make the highs sing. Darker sounding old school amps usually like the treble boosters
Thanks for the constant insight and entertainment Lyle! So how different from the stock Marshall JTM45 did this project end up being? I have a 2005 reissue that I assume has a similar value bright cap on it, but would love to do something to tame the bass a little bit on the bright channel, similar to this Germino.
This was pretty much changing it from an early to a mid-period JTM45.
Spoiler : this amp is coming back in next week for more tweaks. The owner was happy with this but was intrigued when I said it could be tailored even more. He wants more "airiness" - I'm having him bring his cab/speakers too. I need all the pieces of the puzzle.
@@PsionicAudio you mentioned Alnico Blues to pair with this? My local tech suggested the same, or celestial G12h 30 anniversaries. I went with the anniversaries since I have an AC30 w/ the blues that I hope to try with it some day as well.
My Marshall cab came with 2x greenbacks that I found too dark for the JTM45 personally.
Excited for part 2!
The Celestion Alnico Cream is a great sounding speaker as well with a JTM45.
Jimmie Vaughan uses one of their models. That’s a good endorsement!
Grammatico vs Germino?
@@ted149 You’re right sir! Easy to get those two confused. Thanks for the clarification.
@@vayabroder729 cheers bro!
Cool tornado story!
This is a great vid Lyle. I’m way behind on your stuff. Been learning Barry Harris for guitar. I want this amp or one like it! Anyway from few vids back wanted to say… #embarrassmentfee gave me the giggles.
Thanks
JTM45s are dark? Is there some kind of pedal that could, I dunno, theoretically "boost" the treble or something? Maybe there's even a whole boutiquey sub genre of pedals of that nature.
Treble booster gives way to fuzz then your off to the races down in the abyss way down there
Maybe I'm doing something wrong but I got a Catalinbred Naga Viper and the darn thing is so noisy that I cannot use it.
Is that running KT66 output tubes or 6L6/5881? Great video as always.
My amp tech is Lee Jackson of Metaltronix but I do respect your pro level work!
I dig it!
It is my understanding that most tone stacks in tube amps are not active, but actually passive, and that the tone pots only reduce the levels of each frequency they cover and that they are actually essentially out of circuit at full level settings. If that is true, I don't understand why techs often refer to halfway up as flat. No tube guitar amp is designed to be frequency flat like stereo amps because guitar pickups are not flat in their output, rather they tend to be very mid-frequency heavy. Can you explain your perspective on tone pot settings? It sounds like 50% as being flat is an arbitrary statement since most amp tone stacks (such as classic Fenders, Vox and Marshalls) are passive and are not actually flat at all. Please explain further because I cannot reconcile the differences.
It's a very good question. I think the answer will be in video form. Look for it in the coming days.
@@PsionicAudio You might also discuss the fact that Fender intentionally boosted both treble and bass frequency in their tone stacks to make up for the mid-heavy output of guitar pickups, trying to generally flatten out the final output. Marshall did not compensate for this non-linearity of pickup output, thus resulting in the mid-heavy tones of Marshalls vs. the "scooped" midrange of Fenders. It could be argued that by starting with a basic eq of flat, Marshalls actually end up accentuating the mids based on the non-linear frequency response of typical pickup output.
@@PsionicAudio Was this ever addressed, can't seem to find the video response.
I had a germino and it was a mud machine as well.... appeals to those guys playing clean in the house but sounded like hell when turned up
I noticed this turret solder joints right away. They certainly look better now. Did you say that the way they looked when you opened it is period correct?
I like my jtm60 combo with a merc mag tranny and a 12” creamback and phat el34s
JTM45’s sound like a Narrow Panel Tweed Bassman with a little more negative feedback.
Absolutely nothing like the Marshall’s made 5 years later.
The problem here is The Amps OWNER not the Amp or builder
looks like .047 on the PI instead of the 0.1.
I had a Germino 55, and I felt the same way, for me it was muddy, dark sounding. More so at lower volumes. I place a Tim pedal in front of it and it was magic.
Timmy pedal didnt work for it, the Tim pedal worked
I know what with RUclips coloration and my fickle imagination BUT CRIPES,
the V-1 swap?? I preferred the previous and slightly microphonic tube's sound
and smoothness... What is wrong with me?!
...and thanx for yet another great vid, Lyle
Good ear, but I accidentally turned up the Treble while swapping tubes. The first tube I put in was microphonic and I thought I adjusted the volume to check how bad but I accidently turned up the Treble. So you are hearing more there than changing from TAD to Tung-Sol.
Bassman had a bright cap though, did not have a mixer bypass.
How would you rate them compared to Metropoulos amps?
When I build my amps, although they are quiet and easy to access, my pot wires connect on top and look like a bird's nest. How are they connecting their's? IE, the pink wires. If connected under the board on the bottom of turrets, my challenge would be not being able to flip up the board due to both side being wired and immovable. Any insights are appreciated. Thanks!
I’m surprised the amount of difference ~100pF of capacitance added to the right place in an audio amp can make.
I'm baffled by how techs can keep all those specs straight and how they affect sound. I've built and amp and a few pedals, but I daren't stray from the schematic 😂
the coupling caps are all oriented with the outer foils facing the tube side (wrong?) . some say this matters some say it doesn't but i find it peculiar they are all pointed this way
They are all correct but one IMO. Most have the foil to the side of B+ voltage. The 100nf on the left side of the tone stack would theoretically be better the other way as it is closer to ground on that side than it is to B+.
The PI input cap can be done either way - there are arguments for each - but it really doesn’t matter much there.
@@PsionicAudio that's eye opening. i used to go through marking them (with headphones and alligator clips) but not anymore. does it really make a difference?
Not a ton in a relatively low gain amp like this. But best practice is good practice.
Can you do a JTM50 Black Flag build?
Were you wearing your Luftwaffe hat when you did the kick..?
Are jtm 45 usually sound fuzzy like this? I have never tried any non master volume marshall
I have a ‘64 JTM45 I need to check under the hood and compare to this amp….
✌ 🎸
The tornado couldn't kill the amp.
Dang!
Hi Lyle. I built a JTM45 clone thinking I can get great EVH tone. Do you have any mods to suggestion? I really enjoyed your video btw. Thank you. Tom
If you haven't found the answer yet, I might have some information that would help. Essentially convert it to 1968 specs.
@qua7771 No l haven't made any progress on my 45.Thank you for your offer. A 68 conversion sounds very interesting.
@@thomass8472 The 45 has a shared cathode in V1A-V1B. V1B cathode should have its own 2.7K resistor, and .68mf bypass cap. EVH had a 4.7nf bright cap. I would add a bright cap selector switch.
The 45 has a 56K slop resistor in the tone stack. The EVH has 33K resistor in that position.
The 45 doesn't have a cathode bypass cap on the second gain stage V2A to my understanding. The 68SL had a .68uf bypass cap there.
I don't see any filtering between V1, and v2 B+ on the 45. The 68SL had a 50uf filter cap on each side with a 10K 1W resistor between, (usually a single split 3 lead cap 2 x 50uf). On the 45 that filtering is between the cathode follower, and PI. The 68 only has a 10K resistor there, sot the filter caps get moved between V1, and V2.
These are the major differences.
@qua7771 Thank you for taking the time for the directions. I appreciate you and your knowledge. I'll get back to you asap when I have time for some questions once I get started. Unfortunately I'm not sure when. I have some outdoor projects that need to be finished before the cold weather arrives. Thank you again.
@@thomass8472 No problem. So you know, this is not Lyle. My name is Rob, and I have built a few of these, done quite a bit if modification, and am a former Navy avionics tech.
I always like chatting gear in the guitar community. Good people usually. I'll most likely be able to recall these two circuits, as they are the ones I'm most familiar with. All you will need is a few small resistors, and a few capacitors. It's not a complicated process. The hardest part is probably getting your bench set up. Since you built the 45, you already have experience building. The conversion is not a major undertaking at all.
I can also recommend a few minor mods that can get you the sound your looking for.
looks like a 47k slope resistor, should be 56k
That's a subjective thing, and I thought the tonestack sounded fine as Germino built it.
Granted, 5 minutes in...but I swear some people don't turn knobs because some hack told them "every amp sounds best with everything at noon."
If it's dark at noon, um...wouldn't one turn the highs or presence up? Or perhaps move over to the brighter channel?
Continuing...
Tornado resistant amp !
Greg is very adamant to doing repairs, as to keep his amps under warranty and are as DESIGNED.
Be aware of this if anyone owns one.
If one researches the tone they are chasing and chat with Greg, and for me a JTM 45 was not the Marshall sound I have been chasing. His Lead 55LV is what the Doctor ordered.
So if one needs a mod done. Go through Greg.
This amp is built to the spec.
In other words, call Greg if something isn't working to your liking.
Letting local tech interject their ideas and alterations deviate from warranty.
Lesson is: Call Greg before even thinking of calling a local tech.
Unless you don't care about voiding warranty.
Day late n a $$ short, but a simple X line master X the GRIDS of driver tube( p2 p7) wil work better n sound better imho........................old school.....................
😴 P r o m o s m!!!
Owner "plays a Les Paul and likes the blues and classic rock." LOL. Sure he also works a white-collar job, had the amp shipped sight unseen because it was a TGP flavor-of-the-month, and can't play it above 1 because the kids are asleep upstairs. Sad to see amps like this wasted on people who don't know what they're getting and can't play them the way they're intended.
And the douchebag comment of the week goes to!
I frankly don’t like the brightness, I like a thick fat lead sound, with highs. To me, this amp sounds like paper cones ripping.
Sozo caps are a waste of money.
Farty sound. What's allright with this? Probably nothing. The original JTM is different story, but anyway it's not good by design at all.