The Printed Circuit Board (PCB) has arrived from Quick-Teck, much quicker than I had anticipated and looking great. QT have done a fine job, the board looks perfect.
It is twice the normal weight copper, 2Oz as opposed to 1Oz. It is also silver plated as opposed to the usual tin plate and I have kept the track widths as wide as I can to reduce resistance between components. As far as possible I have kept tracks from paralleling each other and as far apart as possible. Likewise distances between components are kept as short as possible. The left and right channels are as symmetric as I could get. Pad sizes are large to increase mechanical strength which is especially helpful when re-soldering components.
There are no electrolytic capacitors in the signal chain, it’s DC coupled but there are electrolytic caps used for de-coupling (sinking RFI away) and local power reservoirs.
I use the word “possible” above a few times but want to point out there is no such thing as a perfect design or perfect layout; the rules governing the layout conflict with each other and compromise is the only way out of these conflicts. All I can tell you is, I have spent many, many hours gradually making ever more minor and minor changes to get the layout as good as I can, given I don’t want to spend too much time over it.
Here’s a pic: