Hi,
I’ve refocused the project a bit since then.
Apologies if my English translations are a bit clumsy.
Here’s an update on the progress of the project after two months of research and design (which is nearing completion).
Firstly, I managed to model Dürer’s solid based on the theory I found most fascinating: Chris Jones’. This guy is absolutely brilliant—he analyzed the perspective down to the pixel using a Python program to determine the geometric proportions of the solid. I built the solid using his formulas. The result is fantastic because the piece is slightly asymmetrical, which I find incredible!
Here’s his study for those interested: https://chrisjones.id.au/Melencolia/index.html.
3D Modeling
The solid is divided into three tiers. The top and bottom will be plywood panels veneered in white ebony.
The edges will have rabbets to inlay brass strips. Some of these will have open joints, particularly between the openwork panels and the frame, as well as between the three tiers.
The central black frame will be made from bog oak.
The openwork panels will be plywood veneered in maple (with a fern-like pattern). The designs will be laser-cut and engraved. These panels will be magnetized into a rabbet in the solid frame.
Panel Testing
Here’s an initial test. Each panel will have a unique engraving. The openwork panels (which will allow sound to pass through) will display a star map of constellations drawn by Albrecht Dürer around 1515. These constellations will be positioned to represent a specific date: the fall of the Ensisheim meteorite on November 7, 1492 (which is also depicted in the background of the Melencolia I engraving where Dürer’s solid appears).
In a way, my solid will feature both a northern and southern hemisphere with cardinal points, symbolizing the meteorite itself, since the sky at the moment of the crash will be "printed" on it.
The woodworking part of the project is coming along. I’ve started my prototype using solid ash and maple-veneered panels.
I’m dedicating my time outside the workshop to researching the electronics for the project. I recently stumbled upon a vintage Leslie-type cabinet for €80. It’s a MacSound Duo de Luxe, made in Italy in the 1970s, for those curious. I restored it a bit and mounted it on a makeshift chassis to make it accessible.
MacSound Duo de Luxe Cabinet
I also took the time to model the parts I plan to reuse (horns, baffles, and pulley system).
Leslie 3D Modeling
Now the first space issues are becoming apparent... The lower baffle is too large for the dimensions I’m aiming for. I can’t enlarge Dürer’s solid for aesthetic reasons (it’s already 625 mm wide). For this baffle, I have two options: either cut down the one I salvaged or make a new one out of wood using a CNC machine.
The rotating horns will be modified to fit upside down, and I’ll order a custom-machined part from the metal lathe in my training center.
I’ve applied to join the Projet G5 forum, a partner of LutherieAmateur. I think it’s better suited for this type of topic. It seems to me that the TechniGuitare forum is more focused on tube amps—correct me if I’m wrong?
As for the electronics, I’m just starting my research and learning the basics, so I’ll share my approach with you. Let’s forget about the double rotating drum idea, haha.
If anyone here has some expertise in this area, feel free to share your thoughts—it would be a huge help! Thanks for your understanding regarding my "knowledge" of electronics.
My current plan is to define a 12" speaker (I initially considered a Celestion G12 NEO Creamback 8 Ohm, but is it really suitable for a Leslie cabinet? I need to dig deeper into this) and a 1" compression driver (still to be decided).
By comparison, the "Leslie" I bought uses an RCF TW101 (which isn’t a compression driver) for the horns and a CIARE M 320.50 C/Fx 12" speaker.
Next, I’ll work on defining the motors I’ll use to replace the HUGE original blocks.
MacSound Duo de Luxe Motor
Here you can see that each rotating system (treble and bass, in this case the treble horns) actually has two motors: one fast and one slow (to achieve the two Leslie cabinet speeds).
My plan is to remove all of this for space reasons and only have two motors in total (one for treble and one for bass). I’ve looked into some DIY projects, and many use DC motors (as mikessi said), but I’m unsure about the best option. It just needs to be quiet and have good torque (DC, servo, brushless?).
To control them, I’m thinking of using an Arduino or a simple circuit to adjust the voltage. Since the baffle and horns rotate at different speeds, I imagine the Arduino would be more versatile and compact.
Finally, for the amp section, I’ll go with a solid-state amplifier for reliability and compactness, as advised earlier in the project. I’ll also need frequency filters—I must admit I don’t have any specific references in mind yet. Ideally, I’d use a compact kit that I can adapt to the cabinet.
On a side note, I managed to get the contact of a Hammond organ restorer in Switzerland. I haven’t reached out yet, but they might be able to help with the project.
That’s my progress and my plans for the future—still a long way to go!
Thank you for taking the time to read this update. This is a translation of the posts I’ve shared on French forums, so I can share them with you here. Thank you for your understanding!
I’ve refocused the project a bit since then.
Apologies if my English translations are a bit clumsy.
Here’s an update on the progress of the project after two months of research and design (which is nearing completion).
Firstly, I managed to model Dürer’s solid based on the theory I found most fascinating: Chris Jones’. This guy is absolutely brilliant—he analyzed the perspective down to the pixel using a Python program to determine the geometric proportions of the solid. I built the solid using his formulas. The result is fantastic because the piece is slightly asymmetrical, which I find incredible!
Here’s his study for those interested: https://chrisjones.id.au/Melencolia/index.html.
Progress on the Cabinet Design:
3D Modeling
The solid is divided into three tiers. The top and bottom will be plywood panels veneered in white ebony.
The edges will have rabbets to inlay brass strips. Some of these will have open joints, particularly between the openwork panels and the frame, as well as between the three tiers.
The central black frame will be made from bog oak.
The openwork panels will be plywood veneered in maple (with a fern-like pattern). The designs will be laser-cut and engraved. These panels will be magnetized into a rabbet in the solid frame.
Panel Testing
Here’s an initial test. Each panel will have a unique engraving. The openwork panels (which will allow sound to pass through) will display a star map of constellations drawn by Albrecht Dürer around 1515. These constellations will be positioned to represent a specific date: the fall of the Ensisheim meteorite on November 7, 1492 (which is also depicted in the background of the Melencolia I engraving where Dürer’s solid appears).
In a way, my solid will feature both a northern and southern hemisphere with cardinal points, symbolizing the meteorite itself, since the sky at the moment of the crash will be "printed" on it.
The woodworking part of the project is coming along. I’ve started my prototype using solid ash and maple-veneered panels.
Electronics
I’m dedicating my time outside the workshop to researching the electronics for the project. I recently stumbled upon a vintage Leslie-type cabinet for €80. It’s a MacSound Duo de Luxe, made in Italy in the 1970s, for those curious. I restored it a bit and mounted it on a makeshift chassis to make it accessible.
MacSound Duo de Luxe Cabinet
I also took the time to model the parts I plan to reuse (horns, baffles, and pulley system).
Now the first space issues are becoming apparent... The lower baffle is too large for the dimensions I’m aiming for. I can’t enlarge Dürer’s solid for aesthetic reasons (it’s already 625 mm wide). For this baffle, I have two options: either cut down the one I salvaged or make a new one out of wood using a CNC machine.
The rotating horns will be modified to fit upside down, and I’ll order a custom-machined part from the metal lathe in my training center.
I’ve applied to join the Projet G5 forum, a partner of LutherieAmateur. I think it’s better suited for this type of topic. It seems to me that the TechniGuitare forum is more focused on tube amps—correct me if I’m wrong?
As for the electronics, I’m just starting my research and learning the basics, so I’ll share my approach with you. Let’s forget about the double rotating drum idea, haha.
If anyone here has some expertise in this area, feel free to share your thoughts—it would be a huge help! Thanks for your understanding regarding my "knowledge" of electronics.
My current plan is to define a 12" speaker (I initially considered a Celestion G12 NEO Creamback 8 Ohm, but is it really suitable for a Leslie cabinet? I need to dig deeper into this) and a 1" compression driver (still to be decided).
By comparison, the "Leslie" I bought uses an RCF TW101 (which isn’t a compression driver) for the horns and a CIARE M 320.50 C/Fx 12" speaker.
Next, I’ll work on defining the motors I’ll use to replace the HUGE original blocks.
MacSound Duo de Luxe Motor
Here you can see that each rotating system (treble and bass, in this case the treble horns) actually has two motors: one fast and one slow (to achieve the two Leslie cabinet speeds).
My plan is to remove all of this for space reasons and only have two motors in total (one for treble and one for bass). I’ve looked into some DIY projects, and many use DC motors (as mikessi said), but I’m unsure about the best option. It just needs to be quiet and have good torque (DC, servo, brushless?).
To control them, I’m thinking of using an Arduino or a simple circuit to adjust the voltage. Since the baffle and horns rotate at different speeds, I imagine the Arduino would be more versatile and compact.
Finally, for the amp section, I’ll go with a solid-state amplifier for reliability and compactness, as advised earlier in the project. I’ll also need frequency filters—I must admit I don’t have any specific references in mind yet. Ideally, I’d use a compact kit that I can adapt to the cabinet.
On a side note, I managed to get the contact of a Hammond organ restorer in Switzerland. I haven’t reached out yet, but they might be able to help with the project.
That’s my progress and my plans for the future—still a long way to go!
Thank you for taking the time to read this update. This is a translation of the posts I’ve shared on French forums, so I can share them with you here. Thank you for your understanding!