A little side use for my arcade machine
It also serves as a very convenient test bench for the displays I’m developing for my future audio projects.
I’m currently using it to prepare the screen layouts for the future Audio Scope, and also the digital wattmeters for my future tube amplifier.
The plan is to use a Teensy 4.1 as the main processor platform in all of these projects. That means I can develop the display routines, graphics, signal processing and user interface here first, then reuse and adapt the same software architecture in the final equipment.
For the Audio Scope, the Teensy will acquire and process the left and right audio signals and generate the data for the displays. For the tube amplifier, the same platform will handle the wattmeter displays and related measurements.
This makes development much easier because I can validate the electronics and software before the final CNC-machined enclosures are completed.
And of course, a lot of this work is being done with the precious help of ChatGPT, which has become a very useful partner for the electronics, software and mechanical design side of these projects.
A little progress update on my audio projects
All the decorative elements are now fitted to the audio streamer, and it is finally starting to look like a real reel-to-reel tape machine. That was exactly the visual effect I was hoping for when I started the project.
I still need to finish the internal wiring, and then comes the moment I’ve been waiting for: seeing the two aluminium reels actually turning. The two stepper motors and the Teensy 4.1 controller are already installed inside.
At the same time, the Audio Scope is also taking shape. The aluminium front panel has now been machined, and it already looks great next to the streamer.
And while those two projects continue, machining has now started on the tube preamplifier as well. The first aluminium panels are done, with the two large openings for the tubes.
Eventually, the idea is to build a complete matching audio system made of five separate units, all sharing the same aluminium design language and all made with my CNC.
Before MillMage, I was a very enthusiastic LightBurn user and used it for many of my projects, mainly in wood. But being able to use MillMage so naturally for CNC machining, especially in aluminium, has completely changed the way I design things.
Aluminium allows me to think about projects in a completely different way: proper front panels, enclosures, mechanical parts and a much more professional overall finish. For me, that changes everything.
What is probably the most surprising part is how much MillMage has increased my motivation to create new things. Since I started using it, I constantly find myself thinking of another project to build. Going from an idea to a real aluminium object has become so straightforward and enjoyable that I just want to keep making things.
So there are still two more units to come after these…
Thanks again to the MillMage team for creating a tool that has genuinely changed the way I approach my projects.
This render shows the final direction I’m aiming for.
Step by step, the streamer, Audio Scope and preamp are bringing me closer to a complete 5-unit matching aluminium audio system.
A little update: the wiring is now finished, and the reels are finally turning!
Seeing the two aluminium reels moving completely changes the look of the project — it really starts to feel like a real reel-to-reel tape machine now.
After all the mechanical work, machining and wiring, this is a very satisfying moment!
It’s just a shame that we can’t post videos here, because the effect is much better when you actually see the reels turning.
Remember that the feed reel turns slower than the takeup reel when first loaded. When the takeup reel is full, the feed reel spins like it is going to come off. 
Youtube the video.
Yes, you’re absolutely right
For the moment, both reels are mainly there for the visual effect, so I’m keeping the animation fairly simple. But now that they’re actually turning, I’m already tempted to make the speeds behave more like a real tape machine.
And yes, YouTube is probably the best solution for the video — I’ll do that so I can show the reels in motion!
I’ve uploaded a short video to YouTube so you can actually see the reels turning. https://youtu.be/RKN8twOHVJ4
Oooohhhh, I could do so much with those reels using a Picaxe controller. You already have a stepper motor controller in there.
- Left runs slow, right runs fast.
- Left speeds up, right slows down.
- Both ramp down to a stop.
- Both reverse (rewind).
- Left runs fast, right runs slow.
- …and so on.
Yes, exactly — that’s the kind of behaviour I’d like to add next
I’m already using a Teensy 4.1 with stepper motor drivers, so I should be able to reproduce all of that in software without adding another controller.
The idea would be to simulate a real tape transport: one reel gradually speeding up while the other slows down, smooth ramping to a stop, reverse/rewind behaviour, and different reel speeds depending on the direction.
Now that the basic motion is working, I think this will be the next fun step!