- Nov 5, 2018
- Calgary, Canada
Obviously the chassis is a non-trivial component of the cost. Tom, you're using the Mini Dissipante 3U 300x330, right? If so, note the base price is $179, so over half the cost Tom quoted above is for custom machining. You can save a lot by doing the machining yourself, or, just go with less machining.
I modify all panels except the top, which drives up the cost, especially at QTY = 1. You could easily drill the holes in the bottom plate and front panel of the MOD286 chassis yourself, provided that you have access to a drill press or drill stand and can drill to a certain depth without punching through the panel. If you have ModuShop do the work, I recommend getting them to machine the rear panel and heat sinks. Most people have trouble with the larger cutouts for the XLR and speakON connectors and with cutting the threads in the heat sinks.
I haven't looked, but I'd be willing to bet you could get an even cheaper case from China (ebay/aliexpress).
A few months later, I found ModuShop and went "aww...." for $20 more than the eBay chassis, I could have had something that would have been of much better quality. Oh, well.
Cheaper still would be to simply buy the required heatsinks, then build a wooden chassis around those (somewhere on diyAudio someone did that with a Mod86 build).
If you have all the tooling and know what you're doing. Otherwise you'll likely spend hundreds on tools, mess it up and have to fork out for more casework to replace the stuff you ruined!
[...]I want my amps to be 300mm wide by 420mm deep, but unfortunately heatsinks will add another 80-100mm to the width.
Another option is to build a pair of dual monos, if the heat cannot be managed. I wonder if anyone has shared their mono 686 build images with you?