# New guitar amp



## Travis (Jun 27, 2021)

Hi everyone! I wanna build one new amp, I love Big clean tones witch a touch of breakup and amps to use with some pedals.

I'm looking ti build jtm45 with ppmv or one TMB 18 watts.

Wich ones Will be better ?

I usually like to play with telecaster, Kliche (Klon) and Paragon (kot)

Thanks for the help guys


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## wintercept (Jun 27, 2021)

I am no amp expert, but I would say go with the 18 watt one. It should still get pretty loud and clean, but you will have that touch of breakup at more reasonable volumes.


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## wintercept (Jun 27, 2021)

Actually just noticed the master volume note for the jtm 45, so that would be a good decision too, maybe even better if the cleans are nicer.

I’m sure others can chime in on the tone and what not. Sorry for any confusion!


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## Travis (Jun 27, 2021)

Thanks ! I'm agree with you but Im not sure.

I never played a real jtm45 or 18 watts TMB


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## jjjimi84 (Jun 27, 2021)

I can speak eloquently on this subject as I have built both. If you want big clean sounds then jtm45 with effects loop and master volume and kt66 tubes is your amp. I would check out valvestorm for parts and you can use the old metro amps kit instructions and have a really great walk through. With single coils and a little delay and reverb it is an intoxicating sound. 

Without a master volume it gets very loud, like very loud. 

Now I have a trinity amps sIII and it is a great sounding amp. The tmb side has some incredible clean sounds and the other channel breaks up early and is a rock and roll machine. This is a better option for jamming around the house without blowing your ears out. I think the 18 watt is a great option for “quieter” playing. 

I don’t think you can go wrong with either option just different levels of loud!


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## Travis (Jun 28, 2021)

jjjimi84 said:


> I can speak eloquently on this subject as I have built both. If you want big clean sounds then jtm45 with effects loop and master volume and kt66 tubes is your amp. I would check out valvestorm for parts and you can use the old metro amps kit instructions and have a really great walk through. With single coils and a little delay and reverb it is an intoxicating sound.
> 
> Without a master volume it gets very loud, like very loud.
> 
> ...


Thanks you very much!

The 18 watts kit I look comes with el84, maybe jtm Ia the way for deep cleans


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## jjjimi84 (Jun 28, 2021)

Travis said:


> Thanks you very much!
> 
> The 18 watts kit I look comes with el84, maybe jtm Ia the way for deep cleans



Yeah for that big bold clean sound i would go that route. I love el84 cleans but they are more focused.

If that makes sense, kind of hard to describe sound. Didn’t Frank Zappa say its like dancing about architecture or something?


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## Travis (Jun 28, 2021)

Could be better choice KT66 on JTM45 than EL34?


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## jjjimi84 (Jun 28, 2021)

Travis said:


> Could be better choice KT66 on JTM45 than EL34?



Absolutely! If you are going to build a JTM 45 then a KT66 tube is the best choice


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## Travis (Jun 28, 2021)

Can I use KT66 on this schematic?

I will buy this https://www.tube-town.net/ttstore/p...marshall---style-jtm45---kt66.html&no_boost=1


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## Travis (Jun 28, 2021)

This is the other option the TMB https://www.tube-town.net/ttstore/tt-kit-marshall-style-18-watt-tmb.html


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## jjjimi84 (Jun 28, 2021)

For the jtm 45 layout from tube town it provides the schematic to use el34 power tubes. To use kt 66 tubes you would need to change the bias resistors r105 to 15k and r106 to 68k and possibly the screen resistors. 

If you are new to building amps and doing those steps seems to much it might be better to stick with the 18watt kit. I would also recommend heading to valvestorm to download the metro amps jtm45 kit guide as it takes you step by step in building that style of amp.


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## HamishR (Jun 28, 2021)

I would always check with the manufacturer or supplier of the power transformer as to whether it can support the power tubes you want to use. But I would say that if the PT can run EL34s it should be fine with KT66s.

My only reservation with building anything with KT66s is that good KT66s are difficult to come by.  Jjjimi is spot-on though when he says that a JTM45 will have a BIG clean sound. And his recommendation of Valve Storm is spot-on as well. The chassis and hardware from Valve Storm are as good as it gets. You can use KT66s, EL34s or 6L6s in a JTM45 usually. I like KT77s which are like a really good EL34.

I've built the TMB MV 18W amp from Trinity and it's not bad but not as big a sound as the JTM45. As Jjjimi says though you can get it sounding good at potentially lower volumes. The other Marshall I would look at - and it is louder again than a JTM45 - would be the 1987. When built in a '67-68 spec it is one of my favourite amps. The low end is more solid than a JTM45s, which can get a bit flabby with extreme drive. It has beautiful cleans if you link the channels with a patch cord and when cranked there are few better sounds in rock'n'roll - and few places you can play that loud unfortunately. But it does take pedals well.

As a pedal platform, a great gigging amp, and something with exceptional clean tones I would recommend something like a Fender tweed Bassman built as a 2x10 or 1x12. You can buy kits for a 5F6-A Bassman and put the chassis in a range of cabinets - Mojotone could probably built you a cab with both a 2x10 baffle and a 1x12 baffle, for example. I have built a few 1x12 Bassmans with Mojo cabs and they sound awesome. After all, the JTM45 was heavily based on the 5F6-A Bassman. The Bassman sounds sweeter and the JTM45 a little more rock, but for the volumes we generally have to play these days the Bassman is possibly a better all-rounder.


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## Travis (Jun 28, 2021)

I build one 5E3 and I like it but I can´t use it with more than 2 on volume, becouse the sound starts being muddy and doesnt take pedals.

Wich speaker will you recommend for 5F6A 1x12? Thanks 


HamishR said:


> I would always check with the manufacturer or supplier of the power transformer as to whether it can support the power tubes you want to use. But I would say that if the PT can run EL34s it should be fine with KT66s.
> 
> My only reservation with building anything with KT66s is that good KT66s are difficult to come by.  Jjjimi is spot-on though when he says that a JTM45 will have a BIG clean sound. And his recommendation of Valve Storm is spot-on as well. The chassis and hardware from Valve Storm are as good as it gets. You can use KT66s, EL34s or 6L6s in a JTM45 usually. I like KT77s which are like a really good EL34.
> 
> ...


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## Travis (Jun 28, 2021)

Anyones know if 18w TMB have more headroom than 5e3? thanks


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## jjjimi84 (Jun 28, 2021)

Travis said:


> Anyones know if 18w TMB have more headroom than 5e3? thanks



Yes it does. I made a bunch of videos on my 5e3 build and the mods I did to correct that low headroom issue. I kept the normal channel stock and altered the bright channel. It made it a much more versatile amp. That may be a route you go for before you build another amp.

But then again I highly recommend building all of the amps, all of them.


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## HamishR (Jun 28, 2021)

I've built a few 5E3s and avoided the mushy breakup thing. It's not difficult and involves a few relatively simple mods. If you want to go the whole hog I recommend using a Mercury Magnetics Fat Stack power transformer -  these transformers have been a huge game changer for me. They allow more current to pass so let the lows though much better without sagging and sounding congested.

Which means reducing the amount of lows in the amp sometimes, and especially in a 5E3. You can do this by reducing the size of the coupling caps and/or the cathode bypass caps.  I also like to use a choke in place of the 5K resistor between the first two filter caps. For speakers I love the Celestion Gold, but a G12H sounds great too.

And again, I completely agree with jjjimi - build 'em all! FWIW I really like the classic 18W circuit with the tremolo. I've built the classic circuit and the TMB version and the tremolo channel is my favourite.


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## Harry Klippton (Jul 1, 2021)

Jesus you guys are gonna make me build a jtm45 aren't you


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## jjjimi84 (Jul 1, 2021)

Harry Klippton said:


> Jesus you guys are gonna make me build a jtm45 aren't you



I can show you some gutshots to really stoke the fire.


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## Feral Feline (Jul 2, 2021)

I'm working on my 5E3 right now, stock build, but can't wait to try a few of the mods suggested here. 

I do like a lot of low end though, so ...


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## fig (Jul 2, 2021)

Feral Feline said:


> I'm working on my 5E3 right now, stock build, but can't wait to try a few of the mods suggested here.
> 
> I do like a lot of low end though, so ...


pizza


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## Feral Feline (Jul 2, 2021)

Settled for Wontons & noodles afterwards. My buddy finished up a birthday-gift Champ for his brother, so we fired up the shop Strat through that and compared CCTs with NOS RCA... OMG, I still can't get over how different and better old tubes are compared to new cheapo stuff. 

My 5E3's board is finished wiring, and some sundries such as caps on pots, grounding of pots, pre-amp tube sockets mounted... next up I'll try to get all the transformer wiring done. 

Next time I'll order the pizza in advance and pick it up for self-delivery; Gotta practice for the job market in Canada...


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## HamishR (Jul 2, 2021)

Well see there's lots of low end and then there's lots of _tight_ low end... In stock form a 5E3 has so much low end it turns to mush because the weeny power transformer can't supply enough juice to reproduce those notes.


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## Feral Feline (Jul 5, 2021)

I like a tight bottom, who doesn't?

HamishR, I defer to your wealth of experience!

I'm a bit of a blank slate (as many have said about me), I'm coming from a bass-sick background so it's good to learn more about guitars, amps, weeny power transformers and tight bottoms.

I'll be back at the 5E3 tomorrow night.


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## fig (Jul 5, 2021)

I'm more of a blank _stare_ kinda guy....add a touch of drool and you've got a full biography.


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## Mrvibes85 (Oct 12, 2021)

HamishR said:


> I would always check with the manufacturer or supplier of the power transformer as to whether it can support the power tubes you want to use. But I would say that if the PT can run EL34s it should be fine with KT66s.
> 
> My only reservation with building anything with KT66s is that good KT66s are difficult to come by.  Jjjimi is spot-on though when he says that a JTM45 will have a BIG clean sound. And his recommendation of Valve Storm is spot-on as well. The chassis and hardware from Valve Storm are as good as it gets. You can use KT66s, EL34s or 6L6s in a JTM45 usually. I like KT77s which are like a really good EL34.
> 
> ...


What filtering do you like for mains, screens, PI and preamp in a 67 or '68 style 1987? And did that era 1987 have the 2.7k and .68 on v1b yet? Do you like the .022 or .0022 coupling cap on bright channel? Sorry for all the questions lol.

Btw I have something weird going on with one amp..maybe you would have an idea? Somehow I can manipulate or subtly seemingly shift the tone if i move any given knob on a pedal plugged into the amp while all pedals are off and true bypass as well (positive). If i strum my guitar and simultaneously move a pot on a pedal that is off I can hear my tone change. This is some marshall clone I bought a few years ago but it's always done this. The guy that I bought it from told me there was some circuitry built into the amp that drains the caps for him so he could mess with it I think...idk but I've never been able to figure it out but its definitely the amp


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## thesmokingman (Oct 12, 2021)

I so wanted to write about the 18 watt's lack of cleans then remembered I built mine away from stock ...


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## danfrank (Oct 12, 2021)

EL84s like it's bigger brother the EL34 tend to break up relatively early because they are true pentodes and not beam power tubes, like the 6L6, KT66, 6V6, KT88, etc.
On similar sized tubes, a pentode will always break up earlier than a beam tube.
To the OP, It depends what you want. You want clean or breakup? You want to practice/gig with it or you want something that won't piss off the neighbors?
Best thing to do is try different amps to give you a general idea of what you're looking for...
To the JTM45 guys... If you're getting to this level of amplifier, spend a little extra and get/build a JTM45/100 type amp. It's one of the best sounding amps ever made... Really, and it's not just a double helping of the JTM45, it's so much more.
And NO master volumes!!! Sheesh...


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## HamishR (Oct 13, 2021)

Hey Mrvibes85: It depends on the sound you're shooting for, but the last 1987 I built had two 50/50 can caps on the chassis and a 32/32 on the board and it sounds incredible! The filters will alter the feel more than the sound. If you use all 50/50s it can get very hard rock, but the differences aren't night and day. 

I started off with the old shared cathodes on V1 - 330µF with an 820 resistor - but in the end I wanted more variation so went with the .68µF/2K7 on the bright channel and a 250µF/1K5 for the normal channel. Historically the normal channel had the 330µF/820R combo but that means the triode is biased quite cold, so I used the 1K5 to give it a bit more pep. You could even use just a 25µF cap there too - it won't really make much tonal difference and might tighten things up a bit. I rarely use a bright cap on the volume pots but did use an 100pF on the bright channel this time and a 470pF cap on the mixers - the 470K resistors linking the channels.

I haven't tried a .0022 on the bright channel as a coupling cap but can see why folks do. I usually play these amps through one or two 12" speakers in an open back cab so like the extra beef of the .022. And I have kept the .1µF PI coupling caps. If I used a quad box I'd probably use .022s there but with open-back smaller cabs I like the extra low end punch.

FWIW I have used 6V6s in plexis before and they work very well to bring the volume down a bit, but they can still be quite loud! They lack the brutal punch of an EL34 but still sound like a Marshall.


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## Mrvibes85 (Oct 13, 2021)

HamishR said:


> Hey Mrvibes85: It depends on the sound you're shooting for, but the last 1987 I built had two 50/50 can caps on the chassis and a 32/32 on the board and it sounds incredible! The filters will alter the feel more than the sound. If you use all 50/50s it can get very hard rock, but the differences aren't night and day.
> 
> I started off with the old shared cathodes on V1 - 330µF with an 820 resistor - but in the end I wanted more variation so went with the .68µF/2K7 on the bright channel and a 250µF/1K5 for the normal channel. Historically the normal channel had the 330µF/820R combo but that means the triode is biased quite cold, so I used the 1K5 to give it a bit more pep. You could even use just a 25µF cap there too - it won't really make much tonal difference and might tighten things up a bit. I rarely use a bright cap on the volume pots but did use an 100pF on the bright channel this time and a 470pF cap on the mixers - the 470K resistors linking the channels.
> 
> ...


Right on, I like the .0022 better for lead playing and the .022 for rhythm but the .0022 as well as the .1 or .047 PI coupling caps give me a nice medium. I think the .0022 allows for a better cranked tone like that IMO with either bucket or singles. I also have never been crazy about volume bright caps unless I'm using a lower value bright mixer cap across the mixing resistors but I think that's because I was always trying to build an amp that teeters on bass and lead specs for the best of both worlds but after having a jtm45 and jtm50 I put together I've learned to embrace the 4700 or 5000pF cap on the volume on lead circuits.

Yeah, I was curious about the filtering because I find conflicting schematics for those years. I like 100 and sometimes 64 for mains on lead models and either 50/50 on PI and screens or 32/32 and I've actually never used anything in the preamp besides a 32/32 in any amp. Depending on the rest of the circuit I find that going from 64 mains to 100 yields a less forgiving tone/feel that sometimes works and sometimes doesnt IME.

I wish I could figure out this old plexi clone, I'm gonna take it apart piece by piece and see if I can hunt down what's going on. To me, the problem seems like a power issue, maybe the PT or whatever "circuitry" the guy had installed to drain the caps. It's the weirdest problem though. Get this, if I am plugged directly into that amp with no pedals in chain but I have a pedal power supply and a few pedals plugged into the same outlet or power conditioner as the amp then I can actually hear the tone change when I turn on the pedals that arent even in the chain! Its not the pedals effect that I'm hearing but theres a small tonal shift and I can even change the sound by turning the pedals controls that arent in the chain. Wild lol.

Edit: I found the problem. It was a tiny string of solder that had dripped from the tab of volume pot touching the rest of the pot.


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