randytsuch's audio page

So here is my SB2 rebox story.

Top still needs painting


In short, it is a SB2, with three Felix’s for power filtering, a bunch of transformers, mostly CRC filtering, a variety of regulators, a built in Burson Buffer, and provisions for adding a Twisted Pear Buffalo DAC later. Clock is a Tent clock XO3.

Here is a pic of the guts, not quite finished, but getting close




Box
Bought a par metal 20-16165A for $64.50 for the chassis plus $15 for internal plate.
This one has “Gold/Clear alodine finish for EMI shield”. Alodine is conductive, so after you screw the thing together, the top makes electrical contact with the bottom, and front and back, as long as you don’t paint over the wrong part. And Aluminum is a good EMI shield.

It is a 16 x 16 x 5 box, so lots of room to put stuff in it, and I plan to use lots of the room

I had some different thoughts about how to handle the display.
I was going to make the entire front out of plastic, and sand everywhere expect a box for the display. I saw a thing where Peter Daniels did something like this, and it looked nice.

In the end, I got lazy. I cut a rectangular hole in the front, a little smaller than the SB2 smoked plastic display front. I then filed the hole a little bigger, until the display would just fit in snuggly, so I could “press fit” the display into the hole. I pressed the display into the front on a flat surface, then epoxyed the display in place, so it won’t come out. I also made a few cutting mistakes, where there were some gaps, and I used epoxy to fill in the gaps.

Not perfect, but it looks OK, as long as you don’t look too close ;).

To mount the actual display, I exposed flat head, number two screws in each corner. The display board has mounting holes in each corner, even though they were not used, but I thank Squeezebox for putting them there. The display is simply mounted with the screws, with a small gap between the display itself, and the smoked plastic.

The first time I tried, I did not use enough epoxy, and some of the screws came off, so this time I used more epoxy




AC Power
When I started this project, over one year ago, I was going to use a Felicia, and a REALLY big transformer. At some point, I decided to take a more “distributed” approach.

I ended up using three Felixes, and a bunch of different, smaller transformers. Pretty much dedicated transformers for different functions.

I did not use the group buy Felix cards, because they took up too much space, so I made a smaller version

Here is the at this time uninstalled IEC jack, with my “fuse” board, and the first felix. The transformer is for powering the burson buffer power supplies



Here it is, after wiring in the switch and IEC, but its harder to see stuff.



The three Felix’s are separated per below:
1. Analog circuits – Burson buffers and analog DAC supplies
2. Digital circuits – Digital DAC supplies
3. Digital circuits - +5 for SB2 and clocks.




These feed the various transformers I have.
Transformers
T1 36VCT, 44VA for Teddy Reg Felix #1 (Analog)
T2 Not installed yet. Felix #1 (Analog)
T3 12.6 VCT 12VA for +5 DAC Felix #1 (Analog)
T4 12.6 VCT 12VA for Display no filtering
T5 Not installed yet 12.6 VCT 12VA for 3.3 V DAC Felix #2 (DAC)
T6 12.6 VCT 12VA for 3.3 V SB2 Felix #2 (DAC)
T7 12.6 VCT 12VA for Clock Felix #3 (SB/clock)
T8 16 VCT 25VA for 5V SB2 Felix #3 (SB/clock)


12.6 VCT 12VA = Hammond 164G12

Picture of power side of box


When the transformers are close to each other, I put them at 90 degree angles to each other, to reduce interaction between them.