Having received the upgrade kit early last week I was eagerly awaiting the replacement resistors all week, and they arrived on Saturday here in the UK. So I got cracking with the second output upgrade. The instructions are up to the usual standard, though I did note that the 220 ohm colour bands were incorrectly stated (as red, red, violet, gold) at various places, not just on page 15 as stated elsewhere. No big issue though.
Assembly was reasonably involved, for me at least. My eyes are definitely acting "middle-aged" these days - I'm 57 - so I made quite a lot of use of an illuminated magnifier, mainly to be sure that the miniscule writing on transistors/regulators and those resistors with tiny writing were correct. And also to be certain that I'd soldered everything properly on the PCB and didn't have any shorts. I think I spent about 4 hours on Saturday, and then another 3 hours on Sunday morning. I'm relatively experienced at soldering and wasn't rushing things, though I made the right decision to down tools on Saturday after 4 hours as I was getting tired and thus more likely to make a mistake.
Anyway, to cut a long story short, after finishing up and having a very careful check for any stray bits of wire in the chassis, I did the voltage check which was fine and then tentatively hooked it back into my system (Roon ROCK -> Ropieee on Pi 4 -> Chord Qutest -> BeePre -> Kaiju -> Klipsch Heresy III and subwoofer). Happily it worked first time.
It's probably too early to state precise changes in the sound and I'm very aware that confirmation bias can play a part. However I can say that kick drums are more "weighty" and the bass in general seems to have more heft. It's a very encouraging start and I'm looking forward to doing a lot more listening over the next few weeks.
Thanks to all for continuing to provide us with fun projects to build, and extremely satisfying audio products that I can't imagine being bettered.
Paul.
