I am looking to Install OT & Choke in a Marshall 2061x H

[sdlogan9]

Hey guys this would be my first time to tinker in side a amp.

I own a solder gun.... what else might I need??

I want to install a O20JM-L Output Transformer and the MC10H choke From Mercury Magnetics into my Marshall 2061x -

any advice you guys can give me would be great - or even some explanation of how to do this..


Peace
Shane

[arwokc]

Are you using a soldering gun or a soldering pen? Careful using a gun as they can get significantly hotter than a pen and can melt your circuit board and destroy components by putting too much heat into them. If you don't have a soldering pen, I would suggest you visit your local Radio Shack or equivalent and spend $20 or less on a pen. While you are there, check out a desoldering tool. They are a life saver and will suck the solder right out of a joint. Make sure you unplug the amp and discharge the capacitors. Also, my mentor, who was an aircraft radio installer and repairman, and whose hobby was working on and building tube radios and ham radios for over 50 years, taught me to never touch the chassis with one hand while working on the circuit with the other. This helps eliminate the possiblity of voltage running through one arm, through your chest (heart) and out the other arm. When you decide to bench test it, make sure it is secure on your bench top. I made the mistake of sitting one of my builds loosely on top of my bench while bench testing it. It began to fall off the bench. My first reaction was to save my countless hours of work from hitting the floor. When I grabbed it, I crossed one of the mains with my thumb while I had a hold of the chassis. My wife swears she heard a little girl scream. I regained the feeling in my thumb a day or two later. You could actually see spots on my thumb where the electricity went in and out. Next I would suggest that you get a schematic of your amp from schematic heaven or a web site similar. Study your transformer connections like you would study a road map before a trip to somewhere you've never driven before and you should be okay.

[statorvane]

never touch the chassis with one hand while working on the circuit with the other.

An excellent pointer. One quick addition here is the "hand in pocket rule" - keep one hand in your pocket while probing with the other. This will prevent an inadvertent electrical shock from crossing your heart.

As far as a soldering pen (or iron), a 40 watt unit should be sufficient. It helps the heat transfer to apply a little solder to the tip prior to heating a joint. And a +1 on the soldering sucker. I have a squeeze bulb which is about the minimum - difficult for me to hold steady with a hot iron in the other hand. Practically useless. I need something better. The spring loaded units that can pull more than a simple squeeze bulb.

A quick question, how do you like the 2061X?

[CaseyJones]

Hey guys this would be my first time to tinker in side a amp.

any advice you guys can give me would be great - or even some explanation of how to do this..

Here's some advice... if you're not a tech take your amp to one. Your Marshall handwired is a fairly expensive piece and not the amp I'd suggest as an appropriate platform to experiment on. You'll end up paying for half an hour of benchtime and your expensive Mercury iron will be an improvement and value-added.

There's a reason that guitars and amps with "pristine untouched solder joints and original parts" sell for a premium. It's the other part of the reason why modded amps and guitars frequently sell for half of what an original piece sells for.

[sdlogan9]

never touch the chassis with one hand while working on the circuit with the other.

A quick question, how do you like the 2061X?

The Amp is smoke'n !!!! I am looking at upgrading the OT & Choke and add some NOS tubes'

I am hopping that I can do the OT and choke my self - although I have never done anything like this, besides installing new pickups in my guitar.

Peace
Shane

[sdlogan9]

Hey guys this would be my first time to tinker in side a amp.

any advice you guys can give me would be great - or even some explanation of how to do this..

Here's some advice... if you're not a tech take your amp to one. Your Marshall handwired is a fairly expensive piece and not the amp I'd suggest as an appropriate platform to experiment on. You'll end up paying for half an hour of benchtime and your expensive Mercury iron will be an improvement and value-added.

There's a reason that guitars and amps with "pristine untouched solder joints and original parts" sell for a premium. It's the other part of the reason why modded amps and guitars frequently sell for half of what an original piece sells for.

Maybe you are right??

But I have to start some where,

Im not afraid !!!

Peace
Shane

[arwokc]

Amen Shane,
If it isn’t broken don’t fix it. The 2061X isn’t a cheap little amp. While you probably won’t affect the value of it today, I would bet you would affect the value of it should you sell it ten years from now. I nearly talked myself into one of those little amps this last year. I love the speaker cabinet that matches that head. There is something to those aged Celestions that really sound amazing, especially for a 2x12. But I built the the Brown Note IIb for a fraction of the cost.
While I have used Mercury Magnetics iron and will continue to do so, I can’t imagine that Mercury knows more about which transformers work best in Marshall amps than Marshall Amplifiers does. Marshall isn’t the biggest name in amplifiers for nothing. I have noticed in the past that Mercury Magnetics has offered a discount on rewinding to people who have an amplifier that Mercury has yet to offer transformers. Now, I couldn’t tell you if Mercury is simply copying these transformers or if they are actually improving upon them. But I do know that Mercury Magnetics is in the business of selling transformers and I keep that in perspective. In all fairness to Mercury, I will say that when I built my Brown Note Lite IIb 18 watt amplifier I used readily available transformers from an internet retailer. These transformers were less than half the price of the Mercury iron and they sounded really good. But, I couldn’t stand not knowing the difference and bought a set of Mercury iron and replaced the previously mentioned transformers. I was surprised in the difference in tone. Now was it really that much better or were my ears prejudiced by my brain knowing what I had paid? Who knows for sure? I will say that my guitar instructor of many years fell in love with the amp and bought it from me. I’ve also built a Hoffman Amps’ Stout designed 18 watt with GDS transformers. That little amp rocks. If I had it to do over, I would build it without the foot switchable relay so that it would have the extra gain stage all the time, and I would try it with the Mercury Iron. Having said all this may I suggest one of the following?

1. Leave the 2061X alone and buy a Brown Note kit without his iron and use your Mercury iron.
2. Visit the Hoffman site and build Stout using the Mercury iron you have.
3. Take a lot of pictures of the guts of your 2061X and build a clone of it with your Mercury iron. This way you could provide a true analysis between the irons. You could provide the forums with valuable input and spec s about your amp. I’ve yet to find a schematic, layout, or detailed photos of a 2061X anywhere. I looked hard and long before I settled on the 18 watters. You’ll have a blast, learn a lot, have forums to provide technical assistance, and you’ll love the fact that you built it with your own hands. But beware, it’s VERY addictive and it isn’t a cheap hobby. I actually enjoy building the amps more than playing guitar. I guess I’m just sick that way.

But hey, the 2061X is your amp, and in the end you are the only person that has to be happy! If all it takes is changing out the transformers to make you happy, go for it.

Good luck Shane,
Andy

[statorvane]

I can’t imagine that Mercury knows more about which transformers work best in Marshall amps than Marshall Amplifiers does.

Yes, you would think that. However, it is apparent that more than a few of the RIs have smoked the PT and the OT while under warranty; required replacement.

The Amp is smoke'n !!!! I am looking at upgrading the OT & Choke and add some NOS tubes'

Hopefully, "Smoke'n" isn't describing the transformers ! The 2061X doesn't have a choke. Do you really need to add one? I mean, if It is smoke'n I wouldn't do anything to the amp except possibly improve the reliability of the transformers.

[muchxs]

I can’t imagine that Mercury knows more about which transformers work best in Marshall amps than Marshall Amplifiers does.

Yes, you would think that. However, it is apparent that more than a few of the RIs have smoked the PT and the OT while under warranty; required replacement.

That might have something to do with the proliferation of power attenuators. The original 18 watt Marshalls were built with the least expensive transformers Marshall could get, they were never designed to be run wide-open. A more durable OT won't sound the same as a close replica of the original transformer.

BTW most manufacturers use the least expensive parts they can find. There were a lot of great sounding tube amps that were built with parts that were very cheap at the time. That's still the case, the difference is that now builders advertise them as the best parts available and the Holy Grail of tone. Maybe they are, maybe they aren't.

[benjoi]

Why are you adding a choke? That will probably change the dynamics of the amp pretty substantially. I've tried a choke in my 18watt Lite IIb and took it out. The reason I took it out is I needed more voltage drop (my el84's were red plating), but I liked it much better without the choke. I'm not trying to talk you out of adding the choke, just curious why your adding one if you like the amp as is.