# Shelly13 - Part1

After playing MobFobAmp for a while, I wanted to take another step in the evolution towards a really good portable instrument combo. With this design I’m trying to address the shortcomings of the previous prototypes:

• Power output could be higher
• More volume in the low lows would be nice
• Folding mechanism a bit fiddly.
• I’d like a one-step unfold, preferably one-handed operation possible
• Mechanical stability and robustness could be improved
• Sensitive components mounted on the outside requiring to be handled with care

## A first design

Taking the above points into account, I figured out that I had to compromise foldability a bit to get all the sensitive components including the speaker chassis to the inside of the cabinet. A ball-shaped design would be ideal for best low frequency / size ratio, but I didn’t know how to manufacture such a design - so I went with a cylindrical approach. I’d like the speaker to “pop up” so it would be protected from mechanical damage when folded. So my first idea looks like this:

## Project constraints

I cannot manufacture the cylinders myself so I’d have to contact a drums manufacturer to send some unfinished custom-size Tom-toms over to me. Even if I get those, I’ll have to cut on a curved surface which I never did before, and I’d require some 3D printing / routing to craft an adaptor plate between speaker and cylinder… Or will I just have the speaker mounted on the top/bottom? Plus, I’d have to think about how to include a more powerful amplifier into my design - there are some ideas like this Pioneer car amp or the specialized Hi-Fi amp from DIY Class D but they have very different and maybe harsh requirements on power supply…

## Conclusion

You see, many open items to think about. I’ll let this sink in for some time before continuing work on this project.

## EdingCNC config

I’d like smooth but quick execution

## My Endmill ‘screams’

Beginner CNC issue: Speeds/Feeds

## CNC Part4 - Setup

Software/Hardware setup & kinematics

## CNC Part3 - Build

Assembling Sorotec’s Basicline 0607

Switch box setup

## CNC Part1 - Portal milling machine

Entry-point and questions

## Inrush Current Limiter - Part2

Circuit & Application examples

## USB Power Delivery

USB-PD power supply explained

## Metabo / Cordless Alliance Systems

Can I use a Metabo/CAS battery for my system?

## Configure MAX1756x for your application

How to set protective voltage & current limits

## Inrush Current Limiter - Part1

Current inrush limiters explained

## Transient Voltage Suppressors

Electronics knowledge: TVS diodes

## Power supervisor MAX1756x on capacitive load

Or how to kill your circuits

## Convert videos with VLC player

How to properly talk to VideoLan’s VLC player

## My Printed Circuit Boards arrived!

Prototype build, issues, improvement ideas for Revision2

How To: First steps with FreeCAD

## How to create better PCB designs

Professionalizing circuits for AnywhereAmps

## Preamp design considerations

AnywhereAmp Alpha’s simple single-supply preamp

## Shelly13 - Part2

Design, folding, stability, amplifiers

## Shelly13 - Part1

Evolving the mobile, foldable instrument combo

## Markdown to PDF

Export the instructions from Markdown to PDF! but how?

## Jekyll: images

Why some images display OK locally but won’t on Github

How to make ToC sticky