Hey all,
I finally finished the DIY Hicap and wanted to report back on the end of the project.
As many of you already know, those caps are bloody dangerous when fully charged - I did the textbook noob mistake of shorting the terminals with a multimeter probe - a big flash and bang, and nicely melted probe tip ensued, but luckily nothing and noone else was damaged. So, I duly did what I should have done earlier and made myself a Capacitor Discharge Tool (otherwise know as a lightbulb!)
:
The transformer I got from Canterbury is a beast - looks lovely and weights a ton!
And here's a close-up of one of the two Sjostrom regulators awaiting fitting in the shoebox case:
So from there I went on to make the split-earth cable - you can see that one plug has 2x24V positive wires, and one 0V earth wire, and then there's a separate 0V earth connection as the only connection on a 5 pin DIN plug which I've plugged in to a free socket (Aux 2) on the Nac202. Thanks to Justin and Mr Tibbs himself for pointers on how this was supposed to work!
Lastly, once I was certain that everything should work I started the final assembly in the case:
I had read that the closer you can get the rectifiers to the caps the better, so I managed to arrange things so that the +ve leg on the rectifier screwed directly into the cap terminal by soldering a washer directly to it. So in the photo of the final assembly below it's quite hard to pick out the rectifiers.
I put a bit of heat transfer compound between the IC heat spreaders and the case sled so that the whole case is acting as a heatsink. I also attempted to keep the +ve and 0V connections to the power supply output as far as possible from each other and from the cable trunk running from transformer to caps, etc.
So, at long last, here's a picture of the final product:
And here it is in my hifi rack, on the right of the middle shelf - no LEDs on the front (just one indicating power running through the rectifiers on the back so you can tell when it's physically switched on), so it's very discreet.
And, wow, does it sound good! I don't need to describe the benefits - I'm sure you all know what they're like. But all the cliches about 'inky black background', 'tighter bass' and 'more space between instruments' is definitely true!
And of course, and most importantly, there's the pride every time I lose myself in a music listening session of looking at my hifi, and specifically the power supply, and thinking "I made that"!!!
Priceless!
So, once again, a huge thanks to Mr Tibbs, and Justin, and everyone else who's given me extremely helpful pointers along the way - I'd never have avoided the plague of the dreaded blue smoke without you!!!
Best
David