I posted this over at the prototype builder's thread, but I thought I'd update the Head-Fi gang as well.
I finally had enough free time yesterday to work on this beauty of an amp. I got the board populated and did the preliminary start up to check voltages. I'm happy to report that everything checked out first try and now I'm ready to move on to wiring and casing it (hopefully tonight after work).
My advice to anyone attempting the build is to work slowly and methodically, and it is a no brainer. The key here is to check and double check everything as you go, looking for solder bridges along the way, because things can get pretty crowded in their, depending on your layout.
My build is slightly different then the 'stock' build because I decided to try mounting all of the taller components under the board, in order to allow the tube to be fully exposed outside of the case. This worked out fine, and am looking forward to getting it inside of the enclosure to verify that it all fits as planned.
A couple things to note - I decided to switch the positions of the leds. I did this with the idea that green means it is powered up, and orange means it is 'warmed up' and ready for music - plus if any light is sneaking out of the enclosure, I prefer a orange glow as opposed to to green. The other thing is the led's I used are kinda oversized for this board, but they were gathering dust in a parts box, so I used them rather than buying new ones. Also, I like to live dangerously and chose to skip both a switch and a fuse, so S1 - S2 is jumpered with a zero ohm resistor. I wouldn't recommend this in general, unless you fully understand the risks...
The BOM is pretty much stock with the exception of substituting Nichicon elctrolytic caps for the Xicons, and pretty much all WIMAs on the films. I used some Vit Q's I had lying around for the bypass positions as well.
With the tube outside of the enclosure, my hope is that the only big heat producer is the voltage regulator, and there will be enough airflow based on this layout to keep it in limits using the BOM heatsink. I chose to mount it under the board with the pins bent at 90 degrees, and the heatsink pointing down. I'm banking on the notion that the heater reg will stay cool enough without a heatsink based on convection airflow. We'll see once she's boxed up...
Here are a few teaser pics from last night...
![](https://www.head-fi.org/attachments/2302823/)