Firstly and most importantly, thanks to my great friend Ralph (@thatBeatsguy on Head-Fi), we have a logo for our Philosophy of Sound high-end brand that I'm actually happy with. Isn't it beautiful? He's also the one behind how well formatted and nice my blog looks and I thought I'd give him a shout-out for it now. I really appreciate the effort he's put in for me so far and I hope he'll be happy to continue working with me.
On to the hardware side. I'd ignorantly assumed that the DiYinHK supplies I've been modelling so far had a fairly low height once assembled but after doing my homework properly and looking up the heights of the caps used, I found out that with all the caps soldered on, this will be the footprint of the 0.8uV bipolar supply used.
Obviously, the whole thing won't look like that in the end but this gives me a rough estimate of the kind of height I have to design for. Considering that the old Soekrates enclosure itself only has a 5" by 7" by 3.6" size, this was a massive oops moment and I had to scramble to change the DAC design fast. I planned to either revert to the old dual enclosure design or come up with a new single-enclosure solution and as I wanted to challenge myself, I went with the latter and so I came up with this.
Much bigger as you can see but this time, everything comfortably fits inside and I think it actually looks nicer than the old design by far. Here's what each of those holes stand for.
As you see, the additional space has allowed me to add a few things to the back panel. Firstly, the coaxial in jack which means the input selection options of this DAC are now complete. Second, there's a master rocker switch in the back which provides a layer of safety due to the dual 115/230V AC in nature of this device so people accidentally plugging it in to mains before checking the voltage don't end up with a $1500 paperweight right off the bat. Finally, there's a flat-head screwdriver-operated sliding voltage selector from Switchcraft that makes it easier for the end user to configure the voltage of this DAC without having to open it up and fiddle around inside.
Of course, the added amount of space gives me much more flexibility to customize where each board goes and I ended up with this for now.
However, even with all of the added space, there really isn't all that much wriggle room to play with as there really is a lot of circuitry. However, the size of the power section compared to the DAC section surprised me quite a bit when I stopped and thought about it. Doubt that's fitting into two separate LC-sized enclosures without some serious compromises like not using a regulated supply for the Soekris board power inputs.
I also left some space between the boards and the panel for all the I/O options as I'm still not 100% sure exactly how it will fit together and won't be until I have all the boards with me. This is because of the unknown size of the custom transformer which until it gets commissioned and made will be hidden to me.
Speaking of the transformer, I found a website which could help me commission what I needed for $65. I had a wacky spec of:
- 0 - 110V - 220V
- 4 x 15V, 0.5A each
- 2 x 7V, 0.5A each
Which I couldn't find anywhere so far, but after a series of emails with Jolin, one of the members of the website, I have a feeling that he can pull off anything I require from him so far.
As for the front of the DAC it remains clean and simple with only a single switch powering it.
However, I decided to switch from Onpow to Schurter as the latter are based in the EU which should make it easier to source the switches. As you can see, they're still extremely aesthetically pleasing and have an array of colour options: the only one missing is amber!
Finally, I decided to switch from the DiYinHK USB to I2S implementation to the WaveIO implementation due to overall consensus that it's superior in general. Had a nice chat with Lucian, the creator of the board, and he's actually a really nice guy and I look forward to doing business with him in the future when I need to buy from him in bulk. In addition, there is an option to remove everything not required (in my case, that's everything except the USB to isolated I2S parts) to lower the end cost of the board which is actually an amazing feature and I applaud Lucian for allowing this option to exist.