OpenSCAD FTW, even for fairly complex stuff using libraries such as BOSL2. It's my first choice for creating template designs that can be rapidly customised for clients.
@alidaf Thanks for mentioning the BOSL2 library, I need to install that. I am a beginner in OpenSCAD. If I was able to somehow import the curves/points generated from ATH4 (as F360 can do) and export a Hornresp record based on the model (as @LORDSANSUI 's FreeCAD models can do), I would need no other CAD. If you have any recommendations for libraries and add-ons, please send me a PM, I would really appreciate that to push myself forward with OpenSCAD.
The great thing is that I can use the instance running at my Linux based home server anywhere and on a phone, too (and so can I now with Hornresp, too).
The great thing is that I can use the instance running at my Linux based home server anywhere and on a phone, too (and so can I now with Hornresp, too).
Nice colour. The CHN-50 is a real giant killer, especially considering price.
How big is the box?
dave
I went from solidworks to fusion360. Solidworks is more complex and quite harder to learn, but in most of what i required it for, it was way overkill, so fusion360 came as a given. Not that hard coming from solid, but may be for someone beginning to use it. Fortunately there are many youtube tutorials, and even forum posts, so it is easy to get help 
The box is 220hx120wx180d external, which I worked out to have an internal volume of just under 3.4l neglecting any lagging and the port. The port is 74.5mm long @ 80mmx10mm, which I calculated to give an F3 of around 72Hz (theoretical) - the actual remains to be seen! The dimensions actually ended up being very similar to the KJF design for a slot loaded box although they started off being a lot wider and shorter, which the wife hated!
Given that this was my first attempt, I was surprised that they sounded as good as they do but I am starting to get a bit picky with them. I've been listening to the whole bunch together rather than piece by piece with any reference gear so I need to pin the issue down a little better. The amp and the DAC will each have their flaws. I will say that they do have an amazing sound-stage though. It's just that some music sounds pretty good while other sounds a little strange - perhaps resonant. Lagging perhaps?
@Brijac As much as I've been pushing FreeCAD, Fusion360 was very intuitive and easy to get into. I just can't use it because of the licensing restrictions. Even though I have released some of my designs as Open Source or Non-Commercial Creative Commons, I want to reserve the right to commercialise, which I'm restricted from doing with Fusion360. I run a social enterprise to help others with autism have access to 3D printing and it earns a modicum from 3D prints that I sell - just enough for filament and occasional repairs, which is fine, but I'd still like to push out at some point to have a proper facility for others to access, rather than my garage!
You know, I considered that at the design stage and even now I'm wondering. I've been relying on whatever tools I can find online, or for free, but they mostly cater for subwoofer design and frequencies below 1KHz. I'd have thought that anything above the Vas would be fine though since it tends to an open baffle and these are full-range drivers. I'd consider boxing a tweeter in but not these, which have a Vas of 1.1l The thing is, when I used wool felt for lagging, it was too thick and it had a really bad effect - it's way better without it.
The one in the image is just an raw ESP32 WROVER fitted onto an expansion board (£2 from Aliexpress). The ESP is a fairly cheap (much cheaper than a RPi) but powerful microcontroller (around £8UK) with Squeezelite-ESP32 firmware. Squeezelite-ESP32 is one of the few open-source attempts at making an equivalent Squeezebox replacement that still uses the Squeezebox Media Server (now called Logitech Media Server). The screen is an SSD1322 but others are supported including ones more typically typically seen on Moode or Volumio players. I made a couple, one with an SPDIF output board and another with a DAC - all nasty cheap but with more upmarket variants on the way. There is also a SqueezeAMP board that I'm making a case for, which is also based on Squeezelite-ESP32 but is an all-in-one board that has a DAC and amp with an optical out. It is also open-source so can be made with the right facilities or bought at cost from the designer - he makes them in batches when there's enough demand and sends them out from Canada. The case for that has a dial a bit like a jog shuttle as well as IR.
Interesting discussion. A few questions:
I have tried and dropped FreeCAD several times over the years with my main issues being lack of assembly and bugs/crashes. Has this improved in recent times?
I have never tried Fusion360 because I do not wish to build a dependency on a current marketing strategy that is almost certainly going to change in the future (been hit by disappearing software more than once in the past). For those that currently use Fusion360 would possibly not being able to use your old models and having to switch to alternative software for future projects be much of an issue?
Has anyone here paid significant sums for a commercial CAD package to support their speaker hobby? Not including CAD packages at/from work.
How do people feel about writing scripts vs GUIs? Won't consider it, tried it but prefer point and click, love it,...?
I have tried and dropped FreeCAD several times over the years with my main issues being lack of assembly and bugs/crashes. Has this improved in recent times?
I have never tried Fusion360 because I do not wish to build a dependency on a current marketing strategy that is almost certainly going to change in the future (been hit by disappearing software more than once in the past). For those that currently use Fusion360 would possibly not being able to use your old models and having to switch to alternative software for future projects be much of an issue?
Has anyone here paid significant sums for a commercial CAD package to support their speaker hobby? Not including CAD packages at/from work.
How do people feel about writing scripts vs GUIs? Won't consider it, tried it but prefer point and click, love it,...?
By the way, fusion 360 allows to export an "archive" file that can be saved locally. As far as i see that's just a disguised "save locally" command.
That allows to keep better control over one's own data and may even allow more than the 10 editable models restriction of private license (not sure about that though).
That allows to keep better control over one's own data and may even allow more than the 10 editable models restriction of private license (not sure about that though).
You might consider looking up a good CAD engineer on Upwork etc (very talented ones are in the Baltic countries and charge quite little). They will have the proper professional software and ability to make manufacturing style drawings. Also, they know tricks so they can draw something in 15min vs 2 hrs if you don’t know the trick.
I personally use SolidWorks (because I learned it at work 20 years ago) and now don’t want to teach myself something new. The learning curve is steep and unless you really want to be a CAD designer, your time is better spent designing electronics or the overall plan and concept.
Autodesk has a 3D package called Fusion360 that has been mentioned several times. For professional use, the subscription cost is reasonable. It’s got a free version for hobbyists but not all features enabled. I have heard SolidWorks to Fusion360 transition is not too bad. But that means steep learning curve if no experience.
The best thing is to watch YT tutorials and start designing basic boxes etc.
Some features I use on SolidWorks to design horns and waveguides, I have not been able to replicate or find in F360. Arbitrary compound curves defined by splines or parametric equations generated using sheet metal lofting techniques is something very handy.
Nowadays you can’t get SolidWorks for a reasonable price. I still use my perpetual license copy from 2009. It’s all about subscriptions now and they run $1.5k to 5k/yr.
Some of the more advanced ones like Catia or Pro-E are in the $25k/yr. Yikes.
The most complex shape made on SW was an adapter that allowed me to fit a woofer to the side of a commercial tractrix horn. This enable me to make a bookshelf point source horn speaker.
But, you probably don’t need this kind of functionality to start with…
I personally use SolidWorks (because I learned it at work 20 years ago) and now don’t want to teach myself something new. The learning curve is steep and unless you really want to be a CAD designer, your time is better spent designing electronics or the overall plan and concept.
Autodesk has a 3D package called Fusion360 that has been mentioned several times. For professional use, the subscription cost is reasonable. It’s got a free version for hobbyists but not all features enabled. I have heard SolidWorks to Fusion360 transition is not too bad. But that means steep learning curve if no experience.
The best thing is to watch YT tutorials and start designing basic boxes etc.
Some features I use on SolidWorks to design horns and waveguides, I have not been able to replicate or find in F360. Arbitrary compound curves defined by splines or parametric equations generated using sheet metal lofting techniques is something very handy.
Nowadays you can’t get SolidWorks for a reasonable price. I still use my perpetual license copy from 2009. It’s all about subscriptions now and they run $1.5k to 5k/yr.
Some of the more advanced ones like Catia or Pro-E are in the $25k/yr. Yikes.
The most complex shape made on SW was an adapter that allowed me to fit a woofer to the side of a commercial tractrix horn. This enable me to make a bookshelf point source horn speaker.
But, you probably don’t need this kind of functionality to start with…
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I found out from my work's SolidWorks rep last week that they offer a $99/year option for non commercial use.
I'll also throw On Shape out there, it has a free tier and was founded by some of the people who started SolidWorks, so consequent has a user experience very similar to SolidWorks.
Someone was mentioning youtube videos earlier but the small number I have seen have been pretty poor. Particularly when compared to the users guide and tutorials that came with the software. Would most people these days look to youtube videos to get going rather than software's documentation?
I was surprised to have similar problems when evaluating OnShape not long after it came out but was less surprised when SketchUp had similar issues. In my case if it doesn't support aerodynamic surfaces (or acoustical surfaces like horns) it is a non-starter. I guess it is likely to be part of the marketing in the case of Fusion 360 to nudge people to upgrade, OnShape when contacted said they would get round to it but it was low priority and SketchUp isn't a conventional full CAD package.
Does the software work on current operating systems or do you need to keep an old version running?
Would hydrodynamic surfaces be a passable substitute? I work in the maritime industry and all the naval architects I know praise Rhino for it's ability to work with surfaces.
Here is an example of the kinds of files I work with when collaborating with a CAD modeler who put my pencil sketch of the A40 amp chassis to a 3D model. He sent me a 142MB STEP file and SW2009 took about 5 minutes to convert to a native SW file. When I got the Thinkpad P16s workstation, it was able to open this file, convert it, and render it in realtime without any issues. My last computer was not a CAD workstation and would just give errors or grind to a halt. Same 32GB memory on both machines.
Some render snapshots:
Photorealistic renders:
Here is a 300mm deep version of the amp playing wonderful music as a 40W Class A amp (above renders are 350mm deep heatsink):
What I love is that everything fits perfectly the first time when stuff is modeled in 3D and manufacturing uses STEP files to produce.
And here is the 350mm deep chassis (no amp installed yet) manufactured from above 142MB STEP file - everything looks and fits perfectly. I’ll need to swap to black screws for production.
Some render snapshots:
Photorealistic renders:
Here is a 300mm deep version of the amp playing wonderful music as a 40W Class A amp (above renders are 350mm deep heatsink):
What I love is that everything fits perfectly the first time when stuff is modeled in 3D and manufacturing uses STEP files to produce.
And here is the 350mm deep chassis (no amp installed yet) manufactured from above 142MB STEP file - everything looks and fits perfectly. I’ll need to swap to black screws for production.
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