Next Build

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JMPGuitars
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Re: Next Build

Post by JMPGuitars »

lavrgs wrote:
Wed 08/19/20 12:59 pm
I've spent some time sourcing parts and planning/scheming I have a couple of general questions.
  • Has anyone developed a front faceplate? I made a custom panel set for my 5E3 build but I'm not sure I want to spend the bux again >>>$150. As an FYI the panels were $70 and the rest was setup and shipping.
  • Can someone explain the 2200uF cap? - it's much higher than most I've seen - what does it get ya?
  • what chassis are people using? My plan is to buy a blank Mojotone chassis and machine it...that way it will fit in the combo cab I have...but I'm also leaning toward building the amp as a head
  • My normal sources don't have 53K resistors... I have 51K and will assume it's "close enough"
  • the WIMA caps are available at mouser but since they are not my go to supplier I would end up paying extra shipping charges... is there a substitute?
  • Sourmash is the current winner for the head cab...should I consider others?
Ouch. Don't waste your money. Talk to [REMOVED] for faceplates and chassis. He can laser/cut them all. That's who makes my stuff for me now. It sounds like you know how to design what you need, and he doesn't charge BS setup fees. Shipping is also reasonable. But I might design a DIY/18Watt.com version of the faceplates and chassis for him to sell as a set...or eventually stock them myself for sale if I make kits. I emailed him about doing that, I'll let you know what he says. I can get the designs to him fairly quickly to produce.

What build are you doing? It sounds like you're doing my Tremolo TMB, but I'm not familiar with a 53K resistor. What resistor are you referring to?

The 2200µF cap tightens up the low end, and reduces noise...also makes the amp play closer to fixed bias while still remaining cathode bias.

It doesn't matter what brand of film caps you use there. Get something around 250V .01µF caps, and you'll be fine.

The thing I like most from Mojo is their cabs. I haven't heard anybody complain about Sourmash for cabs either.

Thanks,
Josh
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Re: Next Build

Post by crgfrench »

There are some 56k...
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Re: Next Build

Post by lavrgs »

JMPGuitars wrote:
Wed 08/19/20 3:04 pm
It sounds like you know how to design what you need, and he doesn't charge BS setup fees. Shipping is also reasonable. But I might design a DIY/18Watt.com version of the faceplates and chassis for him to sell as a set...or eventually stock them myself for sale if I make kits. I emailed him about doing that, I'll let you know what he says. I can get the designs to him fairly quickly to produce. The Mojo chassis costs 45 so it seems reasonable

What build are you doing? It sounds like you're doing my Tremolo TMB, YES
but I'm not familiar with a 53K resistor. What resistor are you referring to?

The 2200µF cap tightens up the low end, and reduces noise...also makes the amp play closer to fixed bias while still remaining cathode bias.

It doesn't matter what brand of film caps you use there. Get something around 250V .01µF caps, and you'll be fine.

The thing I like most from Mojo is their cabs. I haven't heard anybody complain about Sourmash for cabs either.

Thanks,
Josh
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Re: Next Build

Post by JMPGuitars »

lavrgs wrote:
Wed 08/19/20 7:26 pm
Capture.JPG
Yes, that's 56K, not 53K. 56K is a fairly standard value. The part number I use is CMF6056K200FHEK (56.2K).

BTW- I heard back from Carey. It looks like we're going to work out a chassis + panel set for this, and possibly other projects too.

Thanks,
Josh
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Re: Next Build

Post by lavrgs »

Yes, that's 56K, not 53K. 56K is a fairly standard value.
Not sure what I was thinkin'
BTW- I heard back from Carey. It looks like we're going to work out a chassis + panel set for this, and possibly other projects too.
Let me know what happens.
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Re: Next Build

Post by JMPGuitars »

lavrgs wrote:
Sat 08/22/20 10:35 am
BTW- I heard back from Carey. It looks like we're going to work out a chassis + panel set for this, and possibly other projects too.
Let me know what happens.
I already designed the chassis version. I'm working on panel options. I'll make head and combo versions, and give options for the rear panel depending on whether or not people want a footswitch and/or an FX loop. That's like 10 panel designs.

BTW- I updated the layout doc to add mounting holes to the board, and adjust a couple turrets to fit better with mounting. If people drill accurately, it will match the mounting holes on the chassis.
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Re: Next Build

Post by lavrgs »

JMP Is your chassis design anything like the mojotone blank 17"L x 6 1/2"W x 2 1/2"H? I believe this is the chassis for their 18w and also ASSume it is close to the original Marshall...I ask because I created CAD for it and would rather not make LxWxH changes
https://www.mojotone.com/amp-parts/Chas ... um-Chassis
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Re: Next Build

Post by JMPGuitars »

lavrgs wrote:
Sat 08/22/20 1:20 pm
JMP Is your chassis design anything like the mojotone blank 17"L x 6 1/2"W x 2 1/2"H? I believe this is the chassis for their 18w and also ASSume it is close to the original Marshall...I ask because I created CAD for it and would rather not make LxWxH changes
https://www.mojotone.com/amp-parts/Chas ... um-Chassis
The outer dimensions are the same, but my placement of the cutouts is different. If you're concerned about cabinets, the mounting holes are also different, but the mounting holes are the only thing that would really change relative to the cab.

I used the same outer dimensions to keep it simple for cabinets since that is the 18W standard.
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Re: Next Build

Post by lavrgs »

I'm back to thinking about this TMB Trem...

Josh are the chassis and faceplates available? What about your board? Have you decided o supply these? I'm gonna start collecting parts.

General plan is to use the trannies from my Mojotone and maybe a few other items.. new board, new chassis and built in a head cab
Last edited by lavrgs on Wed 03/10/21 9:38 pm, edited 1 time in total.
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Re: Next Build

Post by Bieworm »

lavrgs wrote:
Tue 03/09/21 2:18 pm
I'm back to thinking about this TMB Trem...

JMP are the chassis and faceplates available? What about your board? I'm gonna start collecting parts.
General plan is to use the trannies from my Mojotone and maybe a few other items.. new board, new chassis and built in a head cab
Doing well my friend! You won't regret.
My 3rd one is getting shaped in my head. Different power section definitely.. balancing between 36W and 50W... dilemma dilemma...
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Re: Next Build

Post by lavrgs »

At this point amplifiers are taking a backseat to CNC machine retrofit...with any luck I will be able to engrave faceplates (18watt content)...but the overall performance will be much improved. I do have a few too many amps but when a 4700 pound machine that takes up a lot of space isn't working properly one's priorities need to be adjusted...
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Re: Next Build

Post by JMPGuitars »

lavrgs wrote:
Tue 03/09/21 2:18 pm
I'm back to thinking about this TMB Trem...

Josh are the chassis and faceplates available? What about your board? Have you decided o supply these? I'm gonna start collecting parts.

General plan is to use the trannies from my Mojotone and maybe a few other items.. new board, new chassis and built in a head cab

I don't currently have a supplier for faceplates or chassis. I may wind up investing in a laser machine in the near future.

The boards are available on reverb.com: https://reverb.com/item/40259316-jmpgui ... v1-36-2021

Or you can PM me if you prefer to pay me directly, or if you're international. I'm busy on a work project today, so I might be slow to respond.

Thanks,
Josh
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Re: Next Build

Post by lavrgs »

I don't currently have a supplier for faceplates or chassis. I may wind up investing in a laser machine in the near future.

The boards are available on reverb.com: https://reverb.com/item/40259316-jmpgui ... v1-36-2021

Or you can PM me if you prefer to pay me directly, or if you're international. I'm busy on a work project today, so I might be slow to respond.

Thanks,
Josh
Well Josh,it looks like you want to make it so ANYBODY could build an amp 8-) where do you find the small turrets to fit in those tiny holes...ok I'm done.
Do you have a FAQ page or should we just ask questions indiscriminately...do you have a BOM and suggestions for things like the pedal, are there any instructions? For Example I see the Ruby mod so I'd want to know if it's optional...basic stuff.
I haven't been on the site for a while so if it's been discussed I apologize for not doing a search first
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Re: Next Build

Post by JMPGuitars »

lavrgs wrote:
Wed 05/05/21 5:59 pm
Well Josh,it looks like you want to make it so ANYBODY could build an amp 8-) where do you find the small turrets to fit in those tiny holes...ok I'm done.
Do you have a FAQ page or should we just ask questions indiscriminately...do you have a BOM and suggestions for things like the pedal, are there any instructions? For Example I see the Ruby mod so I'd want to know if it's optional...basic stuff.
I haven't been on the site for a while so if it's been discussed I apologize for not doing a search first
lol! https://youtu.be/NQ-8IuUkJJc?t=75

The download section for the Tremolo TMB has the BOM, layouts, schematics, etc... viewtopic.php?f=25&t=25550

The pedal I have a separate PCB for if you want it, it's normally $15, but I'm bundling it for an extra $10 with the Tremolo TMB PCB. It uses standard LEDs + 3PDT footswitches, or built-in LED 3PDT footswitches. I can supply the parts for the footswitch if you want, but I'd have to figure out how much it all costs. I order stuff like a madman and don't always pay enough attention. 🙄🤣

I started a thread for Tremolo TMB questions: viewtopic.php?f=4&t=25887

Thanks,
Josh
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Re: Next Build

Post by lavrgs »

Josh do you prefer us going to Reverb or will you sell direct?
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Re: Next Build

Post by JMPGuitars »

lavrgs wrote:
Mon 05/31/21 7:12 pm
Josh do you prefer us going to Reverb or will you sell direct?
Either way is fine, PM me if you want to get it directly.

Thanks,
Josh
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Re: Next Build

Post by lavrgs »

I think I sent a PM but when I check my profile its looks like it's empty...
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Re: Next Build

Post by JMPGuitars »

lavrgs wrote:
Fri 06/04/21 11:08 am
I think I sent a PM but when I check my profile its looks like it's empty...
I didn't get anything, shoot me an email instead. support at jmpguitars dot com

Thanks,
Josh
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Re: Next Build

Post by Bieworm »

Just sold a tremolo TMB reverb, so there are now officially 3 tremolo tmb reverb owners
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Re: Next Build

Post by lavrgs »

Does that include future owners...?
I am considering making a chassis, that I will call a composite; it would be constructed of machined side walls and use flat aluminum panels for front back and top. I think I've seen the original JTMs did this. Are there any big negatives? - maybe not practical for mass production but since this TMB board is on the larger size my plan to use a Mojotone chassis may have to be adjusted. What would be the ideal chassis size for the TMB Reverb? The "standard" chassis is 17 x 6.5 x 2.5
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