First I want to say "I LOVE my JMP-1!" I bought it used 4 years ago and use it daily as guitar pre to record not only crunch gtr but great clean tones as well. If you own one of these units and you are not using the effects loop you are missing out. If you want a pro sound that is the way to achieve what you want to hear from your rig. I have an MXR Studio Comp straight in to keep the input tight and Chase Bliss Tonal Recall mono to MXR Phase 99 as a stereo loop. I dial it all in by hand depending on the session usually with the effects tuned in at 3-6. I use 5 different electric gtr rigs but the JMP-1 is my "goto" fav. Unfortunately it has developed a crackle in the last 24 hours and sounds like a tube replacement is in order, which lead me to this vid. So I will say that I listened to this comparison in a studio with pristine monitors and the original tubes have a thicker sound in both distortion and clean channels. Maybe they output more mids and low end. I don't know but I'm worried my tube replacement will alter the tone of my favorite piece of gear. Not much I can do but move forward with some maintenance. If you own one..."Rock on!"
I also love my JMP-1, but I actually think the effects loop is the only really bad thing of this unit. It's basically always leaking a bit of dry signal through (even on '100%' wet) that causes really bad and crappy sounding phase interference if you're using a digital fx unit like a TC G-major. I've de-soldered 2 resistors in mine, cutting the dry signal completely. The dry/wet function doesn't work anymore now (actually you'd need a patch cable on the back from fx-out to fx-in to get any dry signal), and it's basically always 100% wet now. But I guess it's much less of a problem with analog pedals like you're using. Rock on!
After listening again I realized my ears were referencing the last "original tube" clip with OD 2 and bass shift against the "new tube" OD 1 with no bass shift. The new ones are more crisp for sure and tighten up the low end a bit. Sounds great! Keep the videos coming :)
I've been experimenting with pre's a lot in my RM4 (4 seperate preamps that have easy acces to the tubes, so why not?) I found that EH: Tight tube, not much low end, or mids, but very glassy up top JJ: Bottomy, lower midranged, bit of a diminished/rolled off top end Tung Sol: solid bottom, pronounced high-mids, balanced top end Mullard (new generation) bit between the JJ and Tung Sol My general preference is the Tung Sol's, they don't flub in the low end, balanced lower mids prevent boxy-ness, pronounced higher mids allow it to cut through and the balanced top keep things clear but not icepickey But an EH can make a dark/muffled channel brighten up and a JJ can tame a nails-on-chalkboard channel so they have found their uses in my RM4 modules Note: just don't use any tube made by New Sensor in the Cathode follower (tung sol, mullard, sovtek and some other brands) they have a chance to fail in that position
Hi Leon I am going to change my valves in my bought from new JMP 1 after 26 years! Watford Valves uk have been great in suggesting replacements especially for this preamp, Tung Sol looking good. They did suggest changing the onboard battery at the same time after 26 years!! . Did you change your battery by the way and did you back up your presets?
Is there any kind of shelf life to preamp tubes? I bought a Marshall 3-pack as a backup for my JMP-1 back in the 90s, still unopened or used as of 2021.
🤓I perfer the old tubes (less brighter & stiffer) I'm not a fan at all with the "Bass Shift On" that goes with any unit, it looses swank, chime & sag ......just tweek the units more for a warmer natural sound😁
What tubes did you put in there? The difference was night and day! Also, I've heard a few people complain about sound on these units but I didn't notice any in the video. What are thoughts on that?
@@LeonTodd ah cool, thanks for replying! I just grabbed one earlier today. Always wanted one because of the Smashing Pumpkins using it. Great video, thank you for sharing!
I have a question ... does the R channel and the L channel have the same output volume? I use the jmp1 with a fender amplifier and a valvestate and I perceive the difference in volume on the amplifiers....I tried the right channel first and then the left on the same amplifier and I felt the difference .....It's normal? Thanks
They are indeed different..... One side is ' voiced ' fatter than the other, for stereo use. You can ' y' cable them for mono, to get the combined flavour
I've always wanted one of those units, it's just it's very limited on the midi side, what tubes did you put in it anyway, I know this post is a lot late but my first time seeing it.
I need to get an overhaul for mine because I have one JPM preamp and two power amps a 9100 and a 9200. Strange thing is when I got both of them they were loaded with Sovtek's tubes and they sounded pretty sweet. What I want to know is what do you think of the Sovtek tubes and can I get any that can compare to them?
0:44 and 2:52 for comparison. Hard to notice any difference but to me the new tubes seem to have a high freq edge to the sound which is logical with new tubes....
I’ve always wanted one of these Marshall’s. I remember when they came out originally. Are there any long term “maintenance issues” to be aware of if purchasing one now on the used market? Thanks!!
I think OD2 sounds better with new tubes, compare at 1:00 and 3:09. I couldn’t tell much difference with OD1. The clean channels can’t be compared apples to apples because bass shift was on with old tubes, but not on with new tubes.
Sorry, I watched again, and there is a moment where you have Clean1 with bass shift off in old tubes section. Thanks for posting this video! I changed tubes on mine and Now think I liked it better before, but wasn’t sure if it was just in my head. not sure what I put in there…I think a Mullard and a Sovtek. Marshall stock before.
Another great video, Leon! I could definitely tell a difference in the tubes. The crunch in the new tubes sounded much richer to me. I am hoping you can show us how you connect your preamp to Mercurial. Do you run the preamp's line out to your UAD, and then to Mercurial? I'd love to try this with my Triaxis. Overall, how do you like the sounds you can get from this type of setup? Cheers!
It's like the old ones sounded tired and a bit insipid. I went JMP-2 main out - UAD line in - Mercuriall Reaxis with the preamp turned off. Pretty effective setup, I like the Reaxis power amp sim.
HEY BRO WHATS A GOOD TUBE KIT TOO BUY FR THE JCM 2000 LIKE A SERIOUS MOD I CAN DO MYSELF OR HAVE DONE LIKE MAYBE A VODOO AMP MOD THERE BASIC SET UP COSTS $550.00 BUT THEY O SOUND AMAZING AN THEY DO STUFF FOR WARRENB DE MARTINI AN GEORGE LYNCH BOTH THEY USUALLY GET MOORE COSTLY MODS DONE!!!!
Just curious what the original tubes were. I liked them better. The new ones from what I could see looked like groove tubes, not by label but by insides of the tube. Groove tubes are just relabled chinese tubes, they just hand select them but still sound like chinese tubes. They tend to be kinda harsh. Should try some N.O.S. In one amp I use a 40 yr old RCA 7025, and it still works perfectly. But still curious about the ones you took out.
@@LeonTodd I was just wondering which you liked best? I loved the Triaxis that I played but only own the MP-1, great freaking unit. Could never find a decent JMP at a good price and honestly, my dream pre-amp would probably be the Mesa Quad.
Great video! Opening them up and seeing all those parts is impressive. I love my JMP-1. Classic Marshall tone. 2 observations- anyone who says the tubes do nothing in this unit need to see this. Totally disproves that myth, I didn't know they could change the tone that much. The other is I kind of prefer the first set actually. What brand were in and what were the replacements? Also what was your crunch tone settings? Sounded great
Definitely, it's always helpful to do it rather than just read about. They were the stock Marshall tubes that shipped with the unit, I put in some Ruby 12AX7's. The settings were with the EQ all at 0, sounds great!
Cool! You finally tried it! Now get you a JJ, Mullard and a Tung Sol, and try those out. Just do the swap in V2 for the gain channels. only play one rhythm ( maybe even do a DI recording and reamp and loop it so all is exactly the same )The Tung Sol will have way more gain- and noise. Put this myth to bed, LOL!
First I want to say "I LOVE my JMP-1!" I bought it used 4 years ago and use it daily as guitar pre to record not only crunch gtr but great clean tones as well. If you own one of these units and you are not using the effects loop you are missing out. If you want a pro sound that is the way to achieve what you want to hear from your rig. I have an MXR Studio Comp straight in to keep the input tight and Chase Bliss Tonal Recall mono to MXR Phase 99 as a stereo loop. I dial it all in by hand depending on the session usually with the effects tuned in at 3-6. I use 5 different electric gtr rigs but the JMP-1 is my "goto" fav. Unfortunately it has developed a crackle in the last 24 hours and sounds like a tube replacement is in order, which lead me to this vid. So I will say that I listened to this comparison in a studio with pristine monitors and the original tubes have a thicker sound in both distortion and clean channels. Maybe they output more mids and low end. I don't know but I'm worried my tube replacement will alter the tone of my favorite piece of gear. Not much I can do but move forward with some maintenance. If you own one..."Rock on!"
I also love my JMP-1, but I actually think the effects loop is the only really bad thing of this unit. It's basically always leaking a bit of dry signal through (even on '100%' wet) that causes really bad and crappy sounding phase interference if you're using a digital fx unit like a TC G-major. I've de-soldered 2 resistors in mine, cutting the dry signal completely. The dry/wet function doesn't work anymore now (actually you'd need a patch cable on the back from fx-out to fx-in to get any dry signal), and it's basically always 100% wet now. But I guess it's much less of a problem with analog pedals like you're using. Rock on!
After listening again I realized my ears were referencing the last "original tube" clip with OD 2 and bass shift against the "new tube" OD 1 with no bass shift. The new ones are more crisp for sure and tighten up the low end a bit. Sounds great! Keep the videos coming :)
Would be good to have the before and after clips back to back.
I've added timecodes so you can flick back and forth between the first clips
Thanks!
I agree it's very hard to detect a difference.
Seems clearer! I like it :) can def tell during the clean tone
I've been experimenting with pre's a lot in my RM4 (4 seperate preamps that have easy acces to the tubes, so why not?)
I found that
EH: Tight tube, not much low end, or mids, but very glassy up top
JJ: Bottomy, lower midranged, bit of a diminished/rolled off top end
Tung Sol: solid bottom, pronounced high-mids, balanced top end
Mullard (new generation) bit between the JJ and Tung Sol
My general preference is the Tung Sol's, they don't flub in the low end, balanced lower mids prevent boxy-ness, pronounced higher mids allow it to cut through and the balanced top keep things clear but not icepickey
But an EH can make a dark/muffled channel brighten up and a JJ can tame a nails-on-chalkboard channel
so they have found their uses in my RM4 modules
Note: just don't use any tube made by New Sensor in the Cathode follower (tung sol, mullard, sovtek and some other brands)
they have a chance to fail in that position
Hi Leon I am going to change my valves in my bought from new JMP 1 after 26 years! Watford Valves uk have been great in suggesting replacements especially for this preamp, Tung Sol looking good. They did suggest changing the onboard battery at the same time after 26 years!! . Did you change your battery by the way and did you back up your presets?
Is there any kind of shelf life to preamp tubes? I bought a Marshall 3-pack as a backup for my JMP-1 back in the 90s, still unopened or used as of 2021.
🤓I perfer the old tubes (less brighter & stiffer) I'm not a fan at all with the "Bass Shift On" that goes with any unit, it looses swank, chime & sag ......just tweek the units more for a warmer natural sound😁
Leon, excuse me ... what brand new tubes are they? greetings
What tubes did you put in there? The difference was night and day! Also, I've heard a few people complain about sound on these units but I didn't notice any in the video. What are thoughts on that?
Can't remember - may have been some Ruby 12Ax7's
@@LeonTodd ah cool, thanks for replying! I just grabbed one earlier today. Always wanted one because of the Smashing Pumpkins using it. Great video, thank you for sharing!
I prefer the old ones !
Great video! Which brand/type tubes did you use?
I have a question ... does the R channel and the L channel have the same output volume? I use the jmp1 with a fender amplifier and a valvestate and I perceive the difference in volume on the amplifiers....I tried the right channel first and then the left on the same amplifier and I felt the difference .....It's normal?
Thanks
They should be the same; might be down to the different amps or an impedance issue?
@@LeonTodd I tried the right channel first and then the left on the same amplifier and I felt the difference
They are indeed different..... One side is ' voiced ' fatter than the other, for stereo use. You can ' y' cable them for mono, to get the combined flavour
I've always wanted one of those units, it's just it's very limited on the midi side, what tubes did you put in it anyway, I know this post is a lot late but my first time seeing it.
I seem to like the tone with the first tubes better.
I need to get an overhaul for mine because I have one JPM preamp and two power amps a 9100 and a 9200. Strange thing is when I got both of them they were loaded with Sovtek's tubes and they sounded pretty sweet. What I want to know is what do you think of the Sovtek tubes and can I get any that can compare to them?
The Sovtek stuff is pretty great so it might be worth looking for some NOS tubes. The EHX stuff isn't bad but it's a bit inconsistent quality wise.
@@LeonTodd thanks for the tip I just wanted to be dead sure about that. And when the time and money is right I'm putting some fresh ones in.
0:44 and 2:52 for comparison. Hard to notice any difference but to me the new tubes seem to have a high freq edge to the sound which is logical with new tubes....
The new ones are a tad chirpier
Mine sounds tiny in clean channel.. and one of the output sounds hum..
Its because tube?
Voodoo Amps offer a killer mod for the JMP1. Well worth the effort and money.
But, DAMN!, it's a LOT OF MONEY, lol.
I’ve always wanted one of these Marshall’s. I remember when they came out originally. Are there any long term “maintenance issues” to be aware of if purchasing one now on the used market? Thanks!!
I have two and they've been really solid. The washer on the input jack often comes loose but that's about it.
Read this comment reply, reached over and tightened the threaded washer nut on the faceplate input jack...haha
@@nickarmage8311 Hahaha me too. It was really loose indeed lol
I've been playing one for 15 years. Never had an issue.
Thanks for sharing!
I think OD2 sounds better with new tubes, compare at 1:00 and 3:09. I couldn’t tell much difference with OD1. The clean channels can’t be compared apples to apples because bass shift was on with old tubes, but not on with new tubes.
Sorry, I watched again, and there is a moment where you have Clean1 with bass shift off in old tubes section. Thanks for posting this video! I changed tubes on mine and Now think I liked it better before, but wasn’t sure if it was just in my head. not sure what I put in there…I think a Mullard and a Sovtek. Marshall stock before.
What kind of tubes does it originally have ?
Another great video, Leon! I could definitely tell a difference in the tubes. The crunch in the new tubes sounded much richer to me. I am hoping you can show us how you connect your preamp to Mercurial. Do you run the preamp's line out to your UAD, and then to Mercurial? I'd love to try this with my Triaxis. Overall, how do you like the sounds you can get from this type of setup? Cheers!
It's like the old ones sounded tired and a bit insipid. I went JMP-2 main out - UAD line in - Mercuriall Reaxis with the preamp turned off. Pretty effective setup, I like the Reaxis power amp sim.
Those new tubes sound way better, I think they would cut better in a mix!
HEY BRO WHATS A GOOD TUBE KIT TOO BUY FR THE JCM 2000 LIKE A SERIOUS MOD I CAN DO MYSELF OR HAVE DONE LIKE MAYBE A VODOO AMP MOD THERE BASIC SET UP COSTS $550.00 BUT THEY O SOUND AMAZING AN THEY DO STUFF FOR WARRENB DE MARTINI AN GEORGE LYNCH BOTH THEY USUALLY GET MOORE COSTLY MODS DONE!!!!
I don't have any experience with the Voodoo stuff. Look up the choke mod for the DSL, apparently that's the way to go!
Just curious what the original tubes were. I liked them better. The new ones from what I could see looked like groove tubes, not by label but by insides of the tube. Groove tubes are just relabled chinese tubes, they just hand select them but still sound like chinese tubes. They tend to be kinda harsh. Should try some N.O.S. In one amp I use a 40 yr old RCA 7025, and it still works perfectly. But still curious about the ones you took out.
They were Marshall branded, so I'm guessing the original tubes? I need to call my amp tech and see if he has any NOS stuff laying around.
the originals had the Marshall logo
Triaxis vs. MP-1 vs JMP-1. Which is the best?
What tones are you chasing? I'd lean towards the Tri for what I like
@@LeonTodd I was just wondering which you liked best? I loved the Triaxis that I played but only own the MP-1, great freaking unit. Could never find a decent JMP at a good price and honestly, my dream pre-amp would probably be the Mesa Quad.
Great video! Opening them up and seeing all those parts is impressive. I love my JMP-1. Classic Marshall tone.
2 observations- anyone who says the tubes do nothing in this unit need to see this. Totally disproves that myth, I didn't know they could change the tone that much. The other is I kind of prefer the first set actually. What brand were in and what were the replacements?
Also what was your crunch tone settings? Sounded great
Definitely, it's always helpful to do it rather than just read about. They were the stock Marshall tubes that shipped with the unit, I put in some Ruby 12AX7's. The settings were with the EQ all at 0, sounds great!
The new set of tubes sound, not as hot, and a little thinner in the low mids.
New ones sound tighter
More output distortion and sustain
Old tubes have much more character...new tubes are cleaner sounding, but thats not necessarily a good thing
Oh and the tone got bright after the tube Change
The original tubes seems sounds better. The new tubes appears harsh and sour.
Cool! You finally tried it! Now get you a JJ, Mullard and a Tung Sol, and try those out. Just do the swap in V2 for the gain channels. only play one rhythm ( maybe even do a DI recording and reamp and loop it so all is exactly the same )The Tung Sol will have way more gain- and noise. Put this myth to bed, LOL!
2550marshall it would be worth it just to kill the myth once and for all
I much prefer the original tubes.
Cant hear any difference at all
The original valves sounded much better to me.
More punch and mid-range man….