The TeraDak Chameleon DAC ... BAMM Mod
All good ideas but I installed larger feet, quit worrying about the extra heat, and moved on to ...
The BAMM! (Bill Allen Madman Mod)
The Chameleon turned out to be a much easier DAC to Mod compared to the Valab thanks to TeraDak's total redesign. The ground plane is utter “simplicity”, which I of coarse further simplifed. And while I appreciated the extra room to install big dog coupling caps, the space is still insuffecient for my NG (Next Generation) Jupiter 4.7uf caps. Damn! If only the case was as wide as the previous Valab DAC then 4.7uf Boutique Caps would fit perfectly. As is, the space only provides 2.5" L by 3" W and 1.8"H. However if I remove the input board then the Jupiter's "will" fit inside. (And I will be doing just this in the near future when I run I2S direct from the Pace Car to the I2S jumper pins, more on this later).
I bypassed the Spdif selector switch by unsoldering one leg of the Russian input cap and soldering it direct to the RCA jack. It works so perfect, it was as if it was designed that way. Humm! It does however beg for a better quality cap and perhaps a higher quality input transformer ... that is if one wants to go all the way with Spdif.
I removed all 16 little 10uf surface mount caps and installed 16 each 47uf Blackgate FK caps on the DAC chips. There are thoughtfully open holes for doing just this for 12 of the 16 DAC chips. For the final 4 near the front you have to bend the legs and solder direct like we did on the Valab.
I soldered the coupling caps direct to the output of the DAC chip, then soldered the I/V resistor to this same leg. I soldered the other end of the (200 ohm) I/V resistor & RCA ground wires direct to the ground input on the DAC chip board. (This is as direct a connection as you can get … a thing of beauty in my eyes). Interesting, the way Michael laid out the board the filter circuit is still in play. One would have to cut the trace or remove the brown chiclet looking caps to deactivate the filter. I decided to leave mine alone ... for now!
How does it sound? Only time will tell but preliminary results are very positive.
Here are the pictures of The BAMM process.Picasa Web Albums - Bill - Chameleon