The jtm 45100 is a copy of the first marshall 100w stack made for pete townsend consisting of a 100w head and driving an 812 cab. Before doing so with tubes removed measure across your screen resistors to see if they are ok. Mine works best if you whack the speed and intensity full up to get the oscillator circuit running and then run backwards from there, so i. This cabinet is a clone of the marshall jtm45 cabinet. The marshall jtm45 amp head is a lovingly created reproduction of jim marshall s first amplifier. Gibson les paul 1959 tom murphy 20th anniversary with. This is an amplifier made famous by jimi hendrix, but was also invokes tones of early clapton, the young brothers, and other classic rock tones. Legendary tones marshall jtm45 reissue modification. Fender bassman the marshall stack pete townshends guitar gear whotabs jtm45marshall amp.
Some players confuse the black flag nickname with this amp being used by the seminal punk band fronted by henry rollins. Schematics shown in blue are missing from the archive. Marshall metal and block logo jtm45 amp heads,combos and cabs. That sounds like a black flag variation w a 32uf dual external can, 16 uf dual internal can and then a modification w the dual 32 uf on the board w a 10k resistor between the legs to isolate each half to v1 and v2. As you can see from its front panel layout, the jtm45 100 is a traditionally straightforward amplifier. The fender bassman used a 12ay7 as the input tube, but the jtm45 was fitted with a 12ax7ecc83, which has higher gain. The option is to get a marshall 1987x but it is loud.
I would love to know your opinion on the new jtm 452245. Now the classic jtm45 is accessible to all who enjoy its glassy, clean tone and fluid, warm sustain. Jtm45 reissue after modded for kt66 going back to 6l6. The marshall jtm45 is the first guitar amplifier made by marshall. Originally created to respond to the concerns of rock guitarists that existing amplifiers werent producing enough distortion, marshall amps have now become legendary for their sound.
Apr 24, 2009 hello guys, for the sake of practicality i wanted to make this thread pretty much a compendium of the best and coolest mods you can do to a jtm 45. However, more than 10 years ago i was involved in a pretty catastrophic vehicle accident that left me unable to walk for two years. Marshall bluesbreaker broken tremolo my les paul forum. Marshall guitar amps fall into a few distinct categories. I own a marshall jtm45 reissue 2002 that was mod to take valve arts kt66, a tech that no longer is around did only this part of the mod. Marshall amp heaven schematics jtm45 jcm50 jcm600 jcm.
Old power tube sockets were cracked original ot missing as well as. Find reasonably priced marshall amplifiers on ebay. Marshall metal logo jtm45 amp heads,early production mk2. Fender bassbreaker 45 electric guitar amplifier head, 45 watts, free shipping us. Design changes like the use of a sealed cab enabled 20w and soon after, 25w versions to be created a healthy boost up from the original 15w jtm45s. Free shipping on many items browse your favorite brands. Shop for the marshall jtm45 and 1960ax half stack in angled and receive free shipping and. They was used in marshall amplifiers like jtm45 plexi and jmp and in lots tube stuff built in europe during the6070 these caps are renowned for their detailed and clear sound. And are considered hi end components, if you put them in a marshall amp youll hardly notice the difference in sound between these and the mustards.
If you amp is powered off, turn it on and wait a couple of seconds for the os to recognize the marshall code. Youre paying a ton for the collector aspect, but its a fine and good sounding amp. Just a quick unboxing video of my new marshall jtm45 reissue. I spoke with mitch colby from korg usa marshalls us distributor, who told me that the reissues have not undergone any significant changes since their reintroduction 20 years ago. Carter and features exclusive interviews with the greatest names in music. The mix resistors mix both channels together after the first triode sections were originally 270k ohm on the early models. It is also great for general replacement, new oem amplifier builds and d.
The jtm45 marshall s first amplifier was jims version of leo fenders 5f6a tweed bassman amplifier. Today the metal paneled, hand wired marshall amplifiers from 19691973 are the most affordable of the early hand wired marshall amplifiers. There were some very interesting stages of change between the jtm45 amps and the changeover to el34 amps socalled jtm50. Marshall tube guitar heads at a glance display tube guitar heads from. Jtm45 style cabinet black made in the uk modulus uk. Bit of a mismatch actually but its part of what gives the jtm45 its character. If you want marshall style power tube overdrive you need to use el34s with 1k 5. With two channels, four jumpable inputs and a tubedriven tremolo, the kt66powered 2245thw recreates all of the mojo and magic of the amp that kicked off the sound of british rock. I had a quad of jj el34s that kept blowing the ht fuse in a marshall dsl i worked on a few days.
This article tries to give an overview over the early marshall 100 watt amplifiers by piecing together available information and shedding new light on transitional models from 1967. Collector owned and grade, meticulously kept for almost 20 years. The first marshall, the jtm45, used a pushpull power stage identical to the fender bassman 5f6a. If the rg2 is unbypassed as most screen grid resistors are then the larger the rg2 resistance, the more compression you will end up with in the g1 curves. Our version of the classic marshall jtm45 amplifier, circa 1965. The primary reason tube guitar amplifiers are favored over solid state amps is their overdrive tone. Perfect fit for our jtm45 style chasssis or can be used as a template for drilling. Well, you are not going to get the classic marshall brown sound.
This repair guide will show you how to replace the screen on a fossil q marshal gen 2 smartwatch. The jtm45 is a completely different amplifier from the jtm 45100 that wessman is asking about. Mar 25, 2014 by the way, if you like the basic idea of the 2245thw but your wallet doesnt quite stretch to the handwired series or youd like slightly more modern features marshall offers the jtm45 2245 in its vintage reissue series, which does away. Marshall jtm45 reissue modification part ii legendary tones. List of jtm 45 mods you can make metropoulos forum. Marshall jtm45 45w tube guitar amp head musicians friend.
Triode electronics jtm45 layout speaker output notes. While distortion is to be avoided at all costs in audio amplifiers, it is the most important aspect of guitar amplifier design. Marshall jtm45 45w tube guitar amp head guitar center. Again, get a clear picture of what a jtm45 sounds like. Also if anybody has had the chance to get their hands on one of the old ones and what is the difference between the vintage and the new. Now the classic jtm45 is accessible to all who enjoy its glassy. I am running it on top of a 2x12 cab and it sounds great. This amp was made in 1962, not quite in the first 200 but close, made in late 1962 this amp was hand built by jim marshall himself, then later modified by jim as well. I sold a jtm45 ri today and it has always worked flawlessly with me. Marshall jtm45 amp heada lovingly created reproduction of jim marshall s first amplifier.
Jtm45 style front faceplate select your colour modulus. I have never seen one of these available all inclusive before. Marshall went to incredible lengths to achieve maximum authenticity and are delighted to report that their suppliers were equally as exacting in their tasks. Marshall jtm45 turret board layout can be seen at the jtm45 kit layout here. Shop for the marshall jtm45 45w tube guitar amp head and receive free shipping on your order. Marshall took the standard procedure of using 1k screen grid resistors as opposed to the 470ohm resistor seen with beampower tubes. Page 2 1962, the very year in which marshall amplification was born. In 1962, in a small shop in hanwell, jim marshall created and began selling the first marshall amp, a jtm45 tm. Im on my phone and your first pics did not load they have now.
Apr 21, 2009 the reissue marshall was of pcbconstruction, and used the standard parts and components that marshall was building their amps with during that era. It takes pedals better than any amp i have ever had and i have owned many amps in the last 50 years. Marshall jtm45 2245 valve guitar amplifier head pmt online. Opinions on marshalls jtm 452245 page 1 joes guitars. The jcm800 is treble sounding but cranked its the marshall tone. Screen resistors, on the other hand, are handy for eating up excess screen current when the plate voltage is peaking. After the offcenter prototype came the first production jtm45 amp heads, the first 40 made had a full white vynair cloth fronts with smooth black tolex,metal logo,rs transformers, large black choke. The jtm 45100 was always the first amp he plugged into.
Marshall 2245thw jtm45 handwired tube guitar amp head reverb. Sizeh x w x d 229 x 660 x 209mm control panel opening. However, as the voltages crept up in the amplifier over the years, the output stage can still become unstable, especially with the available poor quality el34s. Marshall amplification jtm45 user manual pdf download. In late 1965, marshall introduced its now standard script lettering, in white, and by early 1966 it began calling the amplifiers jtm 50. While the reissue is built with modern components and assembly techniques, it retains much of the. It is very low noise and has all the power you need for any situation. Get the best deals on head guitar amplifiers when you shop the largest online selection at.
A truly iconic amp makes its roaring comeback with the handsoldered issue of the marshall 2245thw, based on the jtm45 head version of the bluesbreaker combo. By the mid 1960s, the jtm45 had become so popular that it began to supplant the ubiquitous vox amps, even their ac50, though it was just as powerful. In fact, the offset head was the first version of the jtm45 my company made and only a mere handful of these heads and cabinets were ever constructed. I have jtm45, jcm900 100 watt, jcm800 50 watt, dsl100 100 watt. Apr 21, 2009 nearly 50 years since its creation, the marshall jtm45 remains both a relevant and nearperfect example of what a great rock n roll tube amp should be. By including gz34 valve rectification, as found in the original, marshall has ensured a faithful recreation of the jtm45 s glorious sound. Marshall jtm45 amplifier headthe marshall jtm45 amp head is a lovingly created. Subsequent marshall designs used el34 pentodes instead of fenders 6l6 beam power tetrodes to create an entirely new sound for which these amps have become legendary. Nov 07, 2014 marshall plexi comparison jtm50 vs jtm45 vs super tremolo vs jmp50 vs super lead vs super bass vs pa duration. This reissue meticulously replicates this original marshall sound. Although some people claim the jtm45 belongs to the plexi group, it sounds warmer and softer and has not such a defined bass and growly midhump.
Ask any guitarist whats most important to them and theyll respond with the same thing tone. You may need to lightly sand the back of the potentiometers to be able to solder the bus wire correctly. How the marshall plexi, 2204 and jcm800 amplifiers work. Marshall jtm45 recently in for repair, this also had several parts replaced with far east, including the 1st preamp cathode bias resistorcap, the 16uf 350v, 56k slope, the 556pf across the 2nd mixer resistor was missing, i also replaced the 16uf32uf can cap. Dont mix up with a jmpplexi thats a different beast.
Lord valves headsup on using kt66 tubes with the jtm45 lord valves field reports indicate that using the valve arts chinese kt66 tubes in the jtm45 reissues and originals can be problematic. The jtm 45 is an all time favorite blues and rock amp. Marshall jtm45 reissue unboxing low quality phone video warning. However at random some of the early amps had serial numbers stamped into the chassis in back. Marshall jtm45 and 1960ax half stack angled guitar center. By the way, if you like the basic idea of the 2245thw but your wallet doesnt quite stretch to the handwired series or youd like slightly more modern features marshall offers the jtm45 2245 in its vintage reissue series, which does away with the tremolo and employs highquality pcb construction rather than hardwired. Dr fixed a marshall jcm2000 dsl401 from completely dead to 100% working better than factory.
The original badgelogo marshall jtm45 is truly an example of a wonderfully responsive guitar amplifier. Fossil q marshal gen 2 screen replacement ifixit repair. Probably no worse than a vox ac30 tremolo, but not in the league of the nice fender ones. Be careful not to damage the wiring or the metal connectors on your smartwatch. Unfollow marshall jtm 45 to stop getting updates on your ebay feed. Nearly 50 years since its creation, the marshall jtm45 remains both a relevant and nearperfect example of what a great rock n roll tube amp should be. Regardless of gear or technique, all guitarists are on their own personal quest for.
List of jtm 45 mods you can make post by coot boy sat apr 25, 2009 1. The screen voltage drop caused by the voltage drop across the screen resistor during heavy overdrive is the main difference in overdrive tone between the el34 and beam tetrode tubes. I do recommend the kt66hp over the shuguangchinese kt66 you have there though. The first 100 watt amps known today as jtm45100s used jtm45 plexi. Gibson les paul 1959 tom murphy 20th anniversary with jtm45 cracked woman tone. This is a great output transformer for jtm45 style amps. Okay, nobody confuses that, but we love family man continue reading british style jtm50. It was originally built around the design of one of jim marshalls favorites, the fender bassman.
The first 100 watt amps known today as jtm45100s used jtm45 plexi faceplates and white super 100 amplifier backplates. The 19651967 marshall super 100 amplifier aka jtm45100. Here it is in its entirety the marshall jtm45 offset half stack reissue. You can think of this as a sort of 100w jtm45, but with solidstate rectification and unique filtering for an amplifier of this continue reading british style jtm 45100 experienced. First produced in 1963, it has been called a seminal amplifier, and is praised as the most desirable of all the companys amplifiers. Finally, in true marshall vintage style, its a crap tremolo. I feel like an idiot asking this question but a friend of mine has an old marshall jtm45 amp with 4 inputs on it. Thats because those first jtm45s were basically cloned from a 59 tweed bassman. Many guitarists who liked the jtm 45 tone but wanted more output power, turned to the jtm 100, that had a power output rating of 100 watts. After the offcenter prototype came the first production jtm45 amp heads, the first 40 made had a full white vynair cloth fronts with smooth black tolex,metal logo,rs transformers, large black choke, leather handle and black pitched top bulgin knobs. Marshall was now known for its distortion and loudness. Marshall jtm 45 offset limited edition stack reverb. The jtm45 2245 is a painstakingly accurate recreation of the very first marshall amplifier, made back in 1962.
A great paper layer wound output transformer with 8k ohm primary for use with kt66 tubes. Marshall sv20h studio vintage 20w tube amp head open box. Because of its consistent popularity, marshall has offered a reissue version of the head more than 20 years after production of the original jtm45 ceased. Marshall jtm 45 offset amp os limited edition discussion in amps. Much closer to a tweed baseman tone than a later era marshall. I know this might be the wrong forum but here goes. Biasing any marshall has many pitfalls, and it will be a daunting task to try and demonstrate the proper way to set up your marshall or any other amplifier equipped with el34s. The marshall jtm45 amp head is a lovingly created reproduction of jim marshalls first amplifier.
Call our experts for product info and phoneonly specials. In a nutshell, here are a few things to watch out for. The tube amp library of information click the link above for tube amp info, schematics, board building information, projects, mods, transformer diagrams, photos, sound clips. Never attempt to replace fuses or valves with the amplifier connected to the mains.
375 1498 1324 1343 379 976 368 11 491 112 795 470 867 655 564 83 908 62 418 18 1477 822 1395 1485 305 1674 1539 1376 569 458 68 368 516 693 381 1090 599 1120 1484