Guitar Gear Forum

Steve (rugbyguitargod) and I traded his Mojotone Brit 800 kit for my Helix LT, so I've got a new kit build on the radar.

The kit is complete: parts, headshell, chassis, tubes, and transformers. Been doing some research on the 2204, and on this particular kit. Seeing that I may need to take some additional steps to properly ground the aluminum chassis. Might need some grommets and other misc. hardware, but that's cool. Am hearing that it might be a bit too much amp for my current needs, but am considering some kind of attenuation, which I've been wanting to get anyways.

Can't wait!

Looking forward to "in process" updates!

Right on!!!! Looking forward to it too!!!

Good deal man. Looking forward to seeing the build thread. I wish I had the skills to build something like that..

And that Behringer attenuator that sells for 100 bucks is really decent with my 2204.

GuitarBilly wrote:Good deal man. Looking forward to seeing the build thread. I wish I had the skills to build something like that..

And that Behringer attenuator that sells for 100 bucks is really decent with my 2204.

Cool!

Glad it went to a good home!! I just didn't have the time/resources to build it and a Helix LT is right up my alley! Can't wait to see the progress and who knows, maybe one day I get a chance to play it at an ampfest or something?!?!

Awesome!

I really want to do a 2204 build kit! I played a proper one at my last AC/DC gig and it fucking RIPPED with the Malcolm Gretsch.

JerEvil wrote:Awesome!

I really want to do a 2204 build kit! I played a proper one at my last AC/DC gig and it fucking RIPPED with the Malcolm Gretsch.

oh damn I can only imagine

rugbyguitargod wrote:Glad it went to a good home!! I just didn't have the time/resources to build it and a Helix LT is right up my alley! Can't wait to see the progress and who knows, maybe one day I get a chance to play it at an ampfest or something?!?!

This will happen. Let’s invade Jer’s place in NV!!!

JerEvil wrote:Awesome!

I really want to do a 2204 build kit! I played a proper one at my last AC/DC gig and it fucking RIPPED with the Malcolm Gretsch.

This is absolutely the kind of tone I’m hoping for with this thing.

GuitarBilly wrote:Good deal man. Looking forward to seeing the build thread. I wish I had the skills to build something like that..

And that Behringer attenuator that sells for 100 bucks is really decent with my 2204.

Gonna get one of those

So… my son is coming out for the week. Tracking shows the kit may be here tomorrow, so it looks like I may be able to have him help me get the kit started together.

This gonna be fun.

Mojotone sells an effects loop kit for $70. Seriously thinking about getting one for this build.

If you’re thinking about that, then look at this.

https://store.metropoulos.net/products/ ... x-loop-kit

Probably very similar but I have this exact loop in my Metroplex and it’s pretty awesome.

Tortuga wrote:So… my son is coming out for the week. Tracking shows the kit may be here tomorrow, so it looks like I may be able to have him help me get the kit started together.

This gonna be fun.

Mojotone sells an effects loop kit for $70. Seriously thinking about getting one for this build.

I really don't know how people run time based effect pedals in front of a 2204. It's so much better in a loop, for me. I would suggest you put a loop in and maybe even get crazy with an external bias trim pot for maximum luxury

RyanDistortion wrote:

Tortuga wrote:So… my son is coming out for the week. Tracking shows the kit may be here tomorrow, so it looks like I may be able to have him help me get the kit started together.

This gonna be fun.

Mojotone sells an effects loop kit for $70. Seriously thinking about getting one for this build.

I really don't know how people run time based effect pedals in front of a 2204. It's so much better in a loop, for me. I would suggest you put a loop in and maybe even get crazy with an external bias trim pot for maximum luxury

I like this thinking - a LOT!

Most definitely get a loop. It's a small cost and it makes the amp much more versatile.

External bias trimpot is also a must have.

greatmutah wrote:If you’re thinking about that, then look at this.

https://store.metropoulos.net/products/ ... x-loop-kit

Probably very similar but I have this exact loop in my Metroplex and it’s pretty awesome.

Thanks, Eric! That’s the one I’ll get

GuitarBilly wrote:Most definitely get a loop. It's a small cost and it makes the amp much more versatile.

External bias trimpot is also a must have.

I’ve been looking at a bias circuit that adds a balance trim pot… given the possible state of tube availability, I’m thinking it might not be a bad idea. Any thoughts?

Note: this is a balance control in addition to the bias current control that I’d be doing. I’ll post up an example later.

Tortuga wrote:

GuitarBilly wrote:Most definitely get a loop. It's a small cost and it makes the amp much more versatile.

External bias trimpot is also a must have.

I’ve been looking at a bias circuit that adds a balance trim pot… given the possible state of tube availability, I’m thinking it might not be a bad idea. Any thoughts?

Note: this is a balance control in addition to the bias current control that I’d be doing. I’ll post up an example later.

yeah I know what you're talking about, the DSLs are all like that, on the 50w you can balance each tube and on the 100w you balance each pair. It's a good circuit, go for it.

GuitarBilly wrote:

Tortuga wrote:

GuitarBilly wrote:Most definitely get a loop. It's a small cost and it makes the amp much more versatile.

External bias trimpot is also a must have.

I’ve been looking at a bias circuit that adds a balance trim pot… given the possible state of tube availability, I’m thinking it might not be a bad idea. Any thoughts?

Note: this is a balance control in addition to the bias current control that I’d be doing. I’ll post up an example later.

yeah I know what you're talking about, the DSLs are all like that, on the 50w you can balance each tube and on the 100w you balance each pair. It's a good circuit, go for it.

Awesome

Hope Steve doesn't mind me reposting his pics here. It's all I've got to go on for now, and this thread desperately needs pics

Normal bias circuit



Modded bias/balance circuit



[credit: RobRob]

How well do greenbacks do with this amp? I'm hoping it'll give me a bit more of the 70s/early 80s vibe that I'm after.

Also, I'm reading about subtle changes between the JMP & JCM circuits - specifically, different dropping resistors that appear to slightly lower voltages on the preamp tubes. Very interested in making this as much a JMP as possible

Marshalls and Greenbacks go together like peas and carrots. Seriously a 2204 should sound awesome through Greenies. Greenbacks, G12H30s and G12 65s would be some of the best speakers for it.

Tortuga wrote:How well do greenbacks do with this amp? I'm hoping it'll give me a bit more of the 70s/early 80s vibe that I'm after.

Also, I'm reading about subtle changes between the JMP & JCM circuits - specifically, different dropping resistors that appear to slightly lower voltages on the preamp tubes. Very interested in making this as much a JMP as possible

Greenbacks are great, no problem there.

The 2204 circuit never really changed much from JMP to JCM. the 2203 did, then changed it further from vertical to horizontal input JCM. But the 2204 remained consistent (well, Marshall was inconsistent with just about everything back then, so there's that... but no real design changes like the 2203 went through).

It’s here!!!!

Pics later. Getting super excited!

Looks like the chassis is steel. Almost disappointed because of all the research I’ve been doing about bonding grounds to aluminum, but glad that won’t be any concern now. This thing is gonna totally kick ass!!!