Vintage Mark-style PCB and chassis kit

[Jay Omega]

Here's a couple other questions:

1. Long head format or short head?
2. Simul-class or 60/100
3. 4/8 or 4/8/16 ohm speaker taps?
4. 120V 60 Hz only, or 100/120/240 50/60 Hz?

 

[edge59AlnicoIV]

Any updates?
Thanks
Ed

 

[Jay Omega]

Any updates?
Thanks
Ed

Getting close! I didn’t get any feedback so I had to make some executive decisions:

1. Long chassis
2. Simul
3. 4/8 only speaker outputs
4. 120V / 60 Hz only

I designed custom transformers for the kit, I’ve ordered one prototype set and should have them in hand this month and will be able to finish the chassis design shortly thereafter. If they’re all good I’ll order 10 more sets for the kits. I’m finalizing the remaining PCB designs, and will get those to the fab shop by next week.

Documentation wise I’ve completed a BOM and a schematic. Once I’m in a holding pattern for chassis I’ll start a wiring diagram.

In short, I’m shooting to make them available this spring. Don’t know cost yet, but hopefully I can keep them in the $1,000-1,500 USD range. If I can get enough people to pay in advance, cost will be lower as I won’t have the financial risk of purchasing items up front that may never sell.

 

[WaxCapacitor]

Hey Jay ,

I lost my password and haven’t been on the site in awhile .

Just changed my password so able to log on .

I’d be into the PCB , long chassis version is fine.

The transformers , it’s something I may be inclined to buy but not something I’d be into at the moment.

What do the transformers include ? Are their any extra taps that are uncommon in other 100 models ?

Thanks for following up ,

Keith

 

[Jay Omega]

Hey Jay ,

I lost my password and haven’t been on the site in awhile .

Just changed my password so able to log on .

I’d be into the PCB , long chassis version is fine.

The transformers , it’s something I may be inclined to buy but not something I’d be into at the moment.

What do the transformers include ? Are their any extra taps that are uncommon in other 100 models ?

Thanks for following up ,

Keith

Hey Keith,

The kits are only going to come in one configuration and will include the chassis, transformer set, PCB set, graphic sliders, and a few other items. The kit will not have everything needed to finish the amp, but will have suggestions for components.

The power and output transformers are modeled after 105 and SC152019B units I was able to test. The power transformer will have a primary electrostatic shield, 120 and 125V primary taps, and the bias winding will have two wires as opposed to one. Aside from that they should be the same as the originals.

Hope this helps!

 

[WaxCapacitor]

I see !

Do you provide a layout for the build ?

Is this a reverb model ?

What’s up with the 125v tap ?

I guess having the transformers on hand would be nice. If it’s a “kit” then I’d assume this is all directed towards the model that implemented 105 transformers . Existing schematics aren’t very intensive , a lot left to be desired !

 

[Jay Omega]

I see !

Do you provide a layout for the build ?

Is this a reverb model ?

What’s up with the 125v tap ?

I guess having the transformers on hand would be nice. If it’s a “kit” then I’d assume this is all directed towards the model that implemented 105 transformers . Existing schematics aren’t very intensive , a lot left to be desired !

The wiring diagram that I was referring to may be what you'd consider a layout, so plan as of this moment is yes.

Yes it will be capable of reverb, a tank will not be supplied but they are available from Boogie.

The 125V tap is for either people who have high wall voltage such as myself, or people that want to run at a slightly reduced voltage.

It's based of a IIC+ DRG, but incorporates some features from later Mark series amps.

I don't think I've ever seen a complete, or accurate schematic of the old Boogies before. You may not appreciate it but I consider it a feat, a lot of time went into it, but moreover I felt it was necessary due to the features I added that weren't included in the originals.

Thanks for the feedback - what is missing from your perspective?

 

[msi]

The wiring diagram that I was referring to may be what you'd consider a layout, so plan as of this moment is yes.

Yes it will be capable of reverb, a tank will not be supplied but they are available from Boogie.

The 125V tap is for either people who have high wall voltage such as myself, or people that want to run at a slightly reduced voltage.

It's based of a IIC+ DRG, but incorporates some features from later Mark series amps.

I don't think I've ever seen a complete, or accurate schematic of the old Boogies before. You may not appreciate it but I consider it a feat, a lot of time went into it, but moreover I felt it was necessary due to the features I added that weren't included in the originals.

Thanks for the feedback - what is missing from your perspective?

You might be able to get some additional interest from the sloclone.com forums. I

The wiring diagram that I was referring to may be what you'd consider a layout, so plan as of this moment is yes.

Yes it will be capable of reverb, a tank will not be supplied but they are available from Boogie.

The 125V tap is for either people who have high wall voltage such as myself, or people that want to run at a slightly reduced voltage.

It's based of a IIC+ DRG, but incorporates some features from later Mark series amps.

I don't think I've ever seen a complete, or accurate schematic of the old Boogies before. You may not appreciate it but I consider it a feat, a lot of time went into it, but moreover I felt it was necessary due to the features I added that weren't included in the originals.

Thanks for the feedback - what is missing from your perspective?

You might be able to get some additional interest from the sloclone.com forum. I know a few people there have asked about kids for Mark style amps.

 

[edge59AlnicoIV]

Hi there, yes, I am interested in PC boards for the IIC+ upgrade, I have the chassis and transformers (Mark III Green stripe), but maybe interested in the 105 transformer if they come available.
Thank you!
Ed

 

[Jay Omega]

Hi there, yes, I am interested in PC boards for the IIC+ upgrade, I have the chassis and transformers (Mark III Green stripe), but maybe interested in the 105 transformer if they come available.
Thank you!
Ed

Hey Ed, I do not have any preamp PCBs compatible with a Mark III chassis at this time, only for a four tube Mark II

 

[Jay Omega]

Should be receiving the prototype transformers soon. Still don't have final pricing, but looking like it will be at least $1500 + shipping per kit. Tentatively, the first round of these kits will come with:

• Chassis + special parts mated to chassis (i.e. IEC inlet, fan receptacle, pilot light)
• Transformers and choke - will come with mounting hardware
• PCB set - will come with mounting hardware for power supply board
• Graphic sliders
• Schematic and wiring diagram
• Recommended parts list
• Maaaybe LDRs

Builders will still have to source things like tubes, sockets, jacks, resistors, capacitors, pots, knobs, wire, etc. Price is higher than I'd hoped, but it's looking like that's the best I'll be able to do. I will have 8-10 available for purchase. Timing will likely be late Spring / early Summer.

What are your thoughts, still interested?

 

[Less02]

Jay, you should definitely produce more PCB. Many might want to convert their B to a C+…. If you can ship only the PCB, I’m in!

 

[Jay Omega]

Jay, you should definitely produce more PCB. Many might want to convert their B to a C+…. If you can ship only the PCB, I’m in!

I do still have a couple preamp PCBs left from the last run, this is the only board needed to convert a IIB to a IIC+. Shoot me a PM and I’ll send you the info

 

[Jay Omega]

These beauties arrived today, I now have all the PCBs needed for the 10 kits.

The prototype transformers showed up last week.

I'm using my Mark III blue stripe to test the transformers, documented in this thread - Mark III HRG Blue Stripe -> DRG No Stripe Conversion. Hopefully I'll be able to call the transformers good in the near future and finalize the chassis design and get those on order, they are the longest lead item at 6-8 weeks. Then it's time to build serial number zero and make them available

 

[Jay Omega]

Got the output and power transformers on order and chassis drawings to the shop for quote and lead time. Here is a sneak peek at the graphics:

Also, a 3D rendering of what the chassis will look like before powder coat:

 

[psychegr]

Got the output and power transformers on order and chassis drawings to the shop for quote and lead time. Here is a sneak peek at the graphics:

View attachment 3240
View attachment 3241
Also, a 3D rendering of what the chassis will look like before powder coat:

View attachment 3242

Great work!

What did you use to do the drawings?

 

[Jay Omega]

Great work!

What did you use to do the drawings?

Thanks! I use AutoCAD and Fusion 360

 

[Hoplite22]

Would love to see the footswitch jack mounted on the rear instead of the front !!! That always bothered me about the old school Mark amps.
It just looks messy having the footswitch input on the front,
Also, an export version would be amazing !!! I would DEFINITELY buy one, and pay for a preorder.

 

[Jay Omega]

Would love to see the footswitch jack mounted on the rear instead of the front !!! That always bothered me about the old school Mark amps.
It just looks messy having the footswitch input on the front,
Also, an export version would be amazing !!! I would DEFINITELY buy one, and pay for a preorder.

This is exactly the function of the lead external switching jack in the rear, you’ll be able to use either

Unfortunately I’m not offering an export at this time. If you can round enough folks for ten units I would consider a special run

 

[Hoplite22]

This is exactly the function of the lead external switching jack in the rear, you’ll be able to use either

Unfortunately I’m not offering an export at this time. If you can round enough folks for ten units I would consider a special run

Yes the lead external switching jack on the rear sounds great, but what I'm saying, is, that the faceplate looks so much more pleasant and uncluttered with the footswitch jack eliminated! You've changed and tweaked the faceplate anyway, so deleting the fs jack won't do any harm.
Just a thought.
Yes, I could always use a variac or step down transformer.