Marshall JMP-1 Tube Pre-Amp

My setup is: Epiphone Explorer Korina with Gibson 500T on bridge, Mesa Boogie 50/50 Power Amp, Korg DTR-1 Tuner and Marshall 1960A cabinet (which sucks. I'm waiting for some custom cabinet based on Eminence V12 speakers which is 100 times better than that Marshall shit. Check http://blackdog.4web.pl if you want some custom stuff in stock prices).
I'm playing hardcore/metalcore and jazz/blues. If you're fan of high-gain this amp is the best choice for 300$. It also has good clean and crunch channel so you use it for any other kind of music. Distortion is brutal, but I think you shouldn't cross 12, cause it losses it's sound a bit.

I think that my JMP-1 is a model built on the end of 90s. This preamp is based on 2 tubes (12AX7) and some Marshall's microprocessor to generate
all Marshall's tones. It's stereo preamp with 2 channels and a 1.5W power amp, so you can use it with headphones.

I'm using it on every gig. It never gave up.

Don't know. Never tried.

I'm playing for more than 8 years now and it's one of the best tube preamp's I've every heard. If somebody will stole it, I'll buy it second time because it's perfect. I think I should change Mesa Boogie 50/50 to 2:90 so the sound will be much brutal and better (but right now it kills most heads - 5150 and mesa dual rectifier).

I use, strats, les paul standards/customs, tele's, PRS, Ibanez, gretch, did I miss any good ones? Sound is solid with limited producers head for the tweek. The JMP-1 is what it is and is definately extremely good at producing a very large array/variety of musical and usable tones, especially when compared to other more current "plastic/aircraft aluminum" preamp gear. With the right components around (which admittedly I have some next to it that cost three times as much)...you can get many new and cool or classic recognized sonic landscapes straight to the mix. But first, you must know that any peice of gear is dependant on the user to find the optimal sound for thier tastes, if you know this you will not be dissapointed with this or many other unique gear as a stand alone. I agree with what many have submitted in this post regarding negative reveiws of gear such as this. To all those eager to say a certain pedal, amp, guitar, or friggen coffee cup, sounds or works like crap based on what is obviously an extremely poor understanding of what it takes to find "your sound". Say one of these simpering impatient limited vision dudes is really into a particular guitar hero, plug them into his stage rig and turn them loose, most likely, they will have it sounding "like crap" in minutes with a wrong turn of this dial or that. Might be fun (if not slightly sad and sadistic) to watch them sweat. Great sound is all about balance. It more often than not begins with compromise (no matter how expensive, basic, cheap, flexible the gear is). You can take any set up and make it sound bad, often it's actually about tuning out what sounds bad to your ears until you have tuned in what sounds badass. This seems fundamental to me and obviously this sentiment is shared by those who are talking sense in these reveiws. In summary, I'll quote the immortal Jerky Boys: "Open your f*&kin ears jackass!" Or go on complaining when you turn to the preset that is named after Steve Via on that little unit you just took out of the box and cry like a school girl when it does not sound "just like that guy".

Flexible outputs/inputs and switching helps for direct recording/various environments. Signal path is kind of a pointless thing to debate at length as a downside in my humble opinion...at the end of the day, what comes out of the speakers/monitors? Good? Bad? Is it you? Is it truly crap? Is it defective? Did you plug it in wrong? Are your cables bad? What's your EQ? Are you an idiot? Check three times and then RTFM (Read The Fricken Manual) again before you rip it up in a reveiw.

Owned mine for over 10 years, purchased when it came first came out, when it was new and risky. Never had a single issue and it was partially submerged in water once.

I know reaching and dealing with Marshall can be a bit...uh...English? But, as point of how they can be once you get in touch: Called Marshall early on when I lost the manual, asked if they could "fax" me one, just so I had it anyway (It's a geek thing). Remember, slightly old school here, before the common use of PDF downloads. They sent me a brand new manual in the same day free...not a big support thing, but just cool.

Been playing for more than 25 years. I am a producer with an independant label, performer, and studio musician. Would replace in a heartbeat, as part of overall guitar preamp collection...just sounds good and have to have it. Grab one on e-bay for $300.00 if you have any doubts.

I play a US Fender strat with Bill Lawrence hum cancelling pickups. In the effects loop I have a Lexicon Delay and BBE Sonic Maximizer. I find this unit works well for what I need it to do. I don't want to distroy the sound of my guitar, I still want the Strat sound at the other end. I like gain, and sustain, but I also like clarity and this unit provides that. The EQ works great on the unit and it is possible to create a wide range of sounds. Its does create a Marshall tone though. If Marshall isn't your taste this unit probably isn't for you. Some of the reviews on this site criticize the unit for having solid state circuits. Most amps and preamps these days have some solid state circuits and that includes the holy grail of preamps, the Mesa Boogie Tri-Axis, so that shouldn't be considered too unusual. In fact the original Plexi's had a solid state recitifier, which together with the EL34 power tubes produced the classic British sound that all the boutique amp manufacturers are trying to replicate. I looked at a lot of preamps before I bought this unit and I think it represents good value compared to equivalent products. I am not sure why some reviewers can't get enough distortion / overdrive with this unit. Even with single coil pickups I can get bags of distortion / sustain. Maybe they need to look at the quality of the pickups on their guitars? A poor quality guitar will still sound poor quality though any amp. Don't listen to these bozos. Try this preamp with a decent guitar and let your ears decide whether this is a good amp or not.

I have a new 2004 model. The design hasn't changed since Marshall started making this unit in the 80's. Preamp has 4 very useable channels. OD1 is crunch, OD2 is metal overdrive and Clean1/Clean2 are clean. Very easy to use, you hardly need the manual. Presets are switchable via midi foot switch or a Marshall foot switch. Has a nice stereo, parrallel effects loop which is programable and allows you to adjust the level of your effects, which is very useful. I play metal and some blues. The JMP-1 does have some solid state circuits, but its sound is predominantly that of a warm tube amp. Does everything I want. I really like the midi control, why would you be without it these days?

I have't had it long enough to rate it. Although it looks a bit old fashioned it is a sturdy unit and I don't expect to have too may problems.

I haven't had to deal with Marshall.

Great unit. Does everything I need it to. Love the midi control and the versatility that provides. Great value for money. This unit will replicate all the classic Marshall sounds.

I use a 2004 Deluxe Fender Strat and a mid 80's Kramer Baretta. The Strat has stock SCN single coils and the Barreta has a JB humbucker. I have a Lexicon MPX 550 and a Behringer Ultrafex Pro running through the effects loop of the JMP-1 to add a touch of chorus, delay and presence. The unit produces very typical Marshall sounds. It is very responsive and punchy and "big" sounding on all channels and really picks up the dynamics of your playing. The OD1 channel is a typical mid 80's type of tone and is great for crunchy Rhythm, OD2 gives a smoother more modern sound with bags of sustain and is good for solos. The clean channels (CL1 and CL2)have plenty of headroom and sound great when you add in a touch of reverb and chorus (with external FX); don't expect the clean channels to sound like a lovelly warm sounding high end Fender tube amp. If you want to cover all the classic Marshall rock sounds from early 70's to the present day then you won't be too dissapointed I think. I generally like 80's and early 90's (pre grunge) hard rock tones and you will be able to cover all the bases with this unit if thats your thing. If you want to make horrendous "nu metal" tones I suggest you get a very cheap transistor amp leave it in a tank of water overnight and then when its dried off buy a nasty japanese guitar with cheap humbuckers, drop tune it and route it to the amp through various distortion and phaser pedals.

Overall this is a great stereo midi pre-amp with four seperate channels each sounding distinctly different. It is extremely easy to use and the EQ section is very effective and capable of making drastic differences to tone and presence. It has great emulated outputs for going direct to my hard disk recorder. The effects loop is very useful and hooking up a good quality FX rack allows you to create some great tones. Pretty much does most things I need. There may be more modern and complex units on the market but I doubt if my patience would hold out while I read the manuals.

Can't say only had it 2 weeks.

No need to contact them yet

I think this is a good quality Pre-Amp that is particulalrly good for direct recording. It produces the full range of classic Marshall tones. I would buy a replacement if it was stolen. I looked at products from Rocktron before buying this but decided that it met my needs better. Although I am sure the Boogie Triaxis is a fine piece of kit and might potentially cover more sounds and offer greater flexibility I just can't see why its more than four times the price (UK street pricing); I do read a lot of reviews where guys appear to be convincing themselves that the thousands of dollars that they spent on their Triaxis was well worth it?

this is the easiest thing you will ever operate nothing else needs to be said.

everyone here must consider that this unit was made 20yrs ago. now for those who've been playing for 2-5 yrs probably couldn't tell you what the deffinition of tone really is. so here's the 28 yr veteran's. my set up consists of marshall '98 JTM45RI 2245 30w with mercury mags output tranny JJ 6l6 and pre's, top hat 2x12 cab w/g12h30 and g12m25 les paul studio,m custom shop strat, 72 thinline, shecter c1-h. i will tell you jwithout the preamp the tone is awsome, with the preamp the tone is enhance tremendously. the only reason the product was purchased was so i could go from sparkle clean to over the top gain and sustain in the flick of a switch. keep in mind that the tonal quality of this piece is very vintage. you can get the modern sound out of it with a little tweeking to the preamp in the head. i would not suggest the use of any effects loop, the reason is, you can fine tune the eq settings with the head unit. you can turn the knob just an 1/8 of an inch and say "wow, i heard that!"

couldn't tell ya, never needed it

same as above

i play everything from blues to metal to classic rock r&b whatever (28yrs), i have other gear jcm800, risson, matchless, yadda yadda yadda. i've tried it with everything and it all sounds good. take the time to play with it, it takes time. use a midi pedal and tune the thing to each one of your guitars so you can have a clean 1&2 OD 1&2 and lead tone if you feel the need. i am putting it in conjunction with a rocktron chameleon for the clean efx and using the jmp for the distorted sounds. if it were stolen or lost, i would replace it.

I am not quite an genie with technical stuff and so on ... but even for me the handling of this unit seems damn easy ...

Just select your Patch, change the Settings to the ones u want save the Patch and thats it ... really damn easy

My Setup is:

Guitars:
Warlock BC Rich (with Gibson LP Standard Pickups)
Richwood LP Pro Series
Amp:
Stinger (a 150w tube amp of Proel)
Effects:
Marshall JFX 1
Tuning:
Korg DTR 2
Noisegate:
Rocktron Hush II CX

The JMP1 fits in perfectly in my collection and makes a damn good sound. I use it that way, that i put my guitar into the DTR, he goes to the Hush, this one again goes into JFX, JFX to JMP and after JMP my Stinger.

The only problem is that the JMP is damn noisy, but seems only with my amp, with an JCM 900 there isnt any problem.

Distorsions and Clean sounds of the Unit are amazing, because of the Tube, thats generating true Marshall Sounds (in my opinion one of the best in world)

The sound Im able to get is damn similair to "Godfather of Hardrock" Slash (GNR), Motorhead, Iron Maiden and if I turn the JMP really up, and combine it with my Warlock, it even sounds a bit like Kerry Kings (Slayer) sound.

The good thing about this unit is also that it has no other Effects except of Distorsion and Clean, thats exactly what I need, because the Effects, the JFX is doing.


9 Points -> because of the Noise, but as I said its probably only with my Amp.

Reliability is TOP ... I even played a lot of Gigs without my Amp only with the JMP directly into the PA, and it sounds damn great too.

Never using any backup, cause there is no need for.

I had never the needing to repair it, even after these 5 years I have it, so i really dont know hows the customer service.

I play true old Hard Rock as Guns N' Roses with my band, with a little portion of Metal, and this unit exactly fits my needs.

I also compared this unit until now with some Zoom's or Digitechs, but the true sound only JMP brings out.

So if I where a new potential customer of a Preamp, I would either by the JMP1 again, or the Mesa Boogie Triaxis.

Hope I helepd

It's quite versatile with it's sounds which can range from sparkling clean to a heavy, sustain filled Overdrive. The cleans break up nicely with high gain (and powerful pickups). It's not noisy but it does physically give off a 'hum' (probably the power supply) but it can't be heard through any of the outputs so I don't mind.
For live use I hook it up through a Compressor/Gate > 31-band EQ > Stereo Digital Effects (for reverb etc) and then into a Marshall 20/20 with a 1922 Cab. For band practice it goes through a Marshall MG30 combo and at home I use the JMP on it's own with headphones.
The speaker emulated outputs are great for recording. The 'Bass Shift' vibrates through your chest when combined with the 'Deep' switch on the 20/20 :-)

1999 model. Lots of options and Easy to use. Plenty of connection options. I never used to like headphones for practice but the JMP seems to have changed my mind. I use the effects loop input to mix in drums and bass etc.

Haven't had any problems with it but the volume settings (not master volume) need to be lowered to eliminate some annoying clipping (even with just the headphones!). I'm not sure if it's just on high output pickups but even the factory defaults needed to be lowered. It also looses volume sometimes within the first few minutes of being powered on but the 20/20 takes a few minutes to warm up too so I don't mind.

The site doesn't have any support contact details and I had some questions about the 20/20 (purchased new) so I submitted it to the 'feedback' page and got a response the next day so I'm quite happy with them.

I got this one second hand with some spare Marshall Valves thrown in. I don't care if it's All-Valve or not, It sounds great! I'm planning to get another one sometime to keep permanently in the rack as removing it after live shows will probably start annoying me.

I placed a submission on 10/23/04 and want to add a significant note. I just exchanged the two original ECC 83 tubes which seems to be of chinese make. These tubes have high gain but no tone! The fuzziness some revieuwers talk about could be caused by the tubes who seem to get worse in time. I now have JJ ECC 83S tubes in the JMP-1 and the sound is much better!! Better means more TONE! The clean sounds to me are warmer but also more brighter and more in balance. The distortion sounds are "cleaner" and have more clarity. At first you think there is a bit less gain but it has just more definition and as I said: TONE! Maybe you have to play more precisely than before but this is what a good (pre)amplifier is about. It let you work a little harder but rewards you with a purer and more versatile sound (still very Marshall thoug). The tubes can be changed easily. Just remove the top cover and the 2 side supports. The tubes can be pulled out and the new ones can be pushed in. If you're not sure about the "do it yourself" you could ask a technician. The JJ tubes are inexpensive but very durable. Of course you can also use tubes from other brands like Svetlana or even the expensive "NOS" Tesla tubes. But it sure can be worthwile to try a pair of new ones!
By the way: the discussion about the JMP-1 not being a pure tube pre-amplifier considering all the ic's and other electronic parts is IMO partly true. I think it IS a compromise of midi, versatility and sound. For the typical purist this unit will never satisfy, even with the better tubes. Therefor you have pre-ampifiers with "all tube design" but not the flexibility (except of course the really expensive once like Soldano). Still, I think the JMP-1 is a good deal considering the price. But you have to decide for yourself as always and just choose what suits you best.

I play classic rock from the 80's in a coverband and use a Marshall 8008 VS poweramp that drives a 1960AV in stereo. First I used the Peavey transistor amps that were standard in the rehearselroom and I didn'like the shrill distortionsound ...sorry Peavey.....however, yesterday I bought a used Peavey classic 50/50 for replacing the valvestate and this will be (much?) better. No Marshall 50/50?? you ask. No.... cause I like a more neutral, heavy sound with lots of warmth, not to agressive. Because that can happen with the JMP-1 easily if the rest of the chaine is also Marshall (but maybe you want this!). And here is a note: ofcourse this is a talk about the JMP-1 but obvious the whole chaine is important! In my set up with the budget 8008 the JMP is sounding very good already which is also due to the 1960AV (very nice cabinet!) I play on superstrats with SD custom 5 pick-ups and recently bought a Boss PW-10 V-wah (replaced my cry-baby). The other guys of the band are enjoying the sound I get and dont't run away, so thats a point for Marshall. As said, things will improve with the Peavey 50/50 (more warmth and dynamics). The JMP is controlled by a Digitech midi floorboard and switching is accurate and flawless. In the beginning I had to tweak the eq much, but now it is set right and it will do fine. I'm very happy with the unit. At home I record instrumentals in my studio and I must say that the direct recording with the compensated outputs is amazing! The trick here is to use the proper effects so the dry sound is given a good live ambiance. Blend in the mix the sound is convincing and pure. It isn't the same as miking your cabinet, that will always be better (more lively). Clean sounds are good enough for me but I can understand the critics.

Well..... it sounds good, plenty of gain, is relatively noisefree (not the OD2), very versatile and affordable.

Bought it 3 years ago in Holland. The features are incredibel and very well designed. The ease of switching your channels together with matched effects is the bonus and the device is very easy to operate too. Important is to have patience! Figure out what it can do and have an open mind to the possibilities. The comments I read are not always fair I think, because you just have to know how to use it. As we all know, good (pre)amplifiers let you work on your guitarplaying a bit more but the result is much better for your tone. The control of your guitar is the issue here and try to play your axe right first instead of blaming equipment for a crappy sound! Another thing is personal taste. A device suits you or not. But most of the equipment nowadays is build well and will have a good sound for the right purpose AND player. But for the JMP-1, it suits me and I manage to get the Marshall sounds that I always liked. I think the eq could have been more versitale, but all the sounds are there! On higher volume this baby does sounds better but what doesn't......

I have not used this unit intens yet but have no problems. Only thing is that the dataknob skipps presets now and than. That can get on my nerves sometimes. Seems build ok and I don't expect serieus problems.

I,ve been playing for 26 years and recently started a new rockband with my brother on drums so we try to be Van Halen!! ;-) The gear I use is already mentioned but I also use an Alesis Quadraverb but will replace it. Further more Fender Stratocaster usa, Maverick X-1 (I won this sucker in a contest!) and I have a small home studio for recording rock instrumentals. When stolen, I would look around for the new developments that have come up but knowing this JMP, I will set it on top of the list for now.

Finally, as said earlier.....work on your tone and talent and be sure to judge equipment fiarly, and don't blame it when you have a bad playing day or have not been practising enough! Cause there is a chance that the equipment has a higher quality level than yourself. But it won't judge you!!
Have fun.....

All Rock styles played.
I use a Schecter Hollywood custom with Seth Lover pickups, a G-Major effects rack and a Behringer footpedal to control both. I put the whole thing through a 2020 El84 Marshall valve amp and a Marshall 2 x 12. IT ROCKS. When I get the orignal greenbacks (sitting in my attic) into the Cab I am sure it will be awesome.
I also have an 80-80 valve state as a live back up but it really sucks through that and I hope I never have to use it.
Have recently revalved the whole rack (after chatting to Derek at Watford Valves) and fitted a clean valve to the clean channels and a Groove tube mullard reissue to the distorted channels.
Clean is so good now, clean, lively full bodied and excellent clarity.
Distorted is excellent with more sustain than Lesley West and a good crunch sound for Rythmn.
I am still in the process of setting it all up and getting the clean/distorted/rythm/lead balances right. However, even at 40 Watts total output (I would say that is in reality "nominal") and I can still cut it in a really loud band without any effort with power amp on 50%.
Not massively noisy, but you need a noise gate in high gain.
Gives loads of Marshall sounds a lower volumes. OK it will never match the full marshall stack at "number 11" on the vol. but what do you want!!!!!!
It gets a 9 cos I don't give 10s

ALready mentioned so many times not worth repeating. Read the other reviews.
Always use a good valve power amp.
And ignore those "experts" who say that they know about valves and op amps. The valves add more than "colour" they are part of the amplification circuit.
I use different valves for clean and distorted and get an excellent sound.
Versatility with the variety of songs we play and the fact that I am not only the sole guitarist but also do PA and backing vocals means I love the ease of use the MIDI offers.

Never gone wrong on me
But to get the best, you need to look after it a little. Make sure you got room in the rack for cooling.
Use a valve power amp and again leaver it space to get rid of the heat. Will improve lifetme and reliability.

Never dealt with them. Never gone wrong

Been playing longer than I care to think about, more than 1/4 century, mainly as bass. Always played guitar but last two years solely guitar.
Technically competent, electronics and hardware. Service my own gear.
Input on the back only thing missing.
Noted the problem mentioned with the data input where it skips a couple of digits. Turn it slow and it's OK. Suspect some switch debouncing needed.