process, but it’d be easy enough to have it up on a laptop
or tablet nearby to save a few trees.
I followed the build instructions as written to get the
full experience of the kit. First up were the amp modules.
There are two identical amplifier modules in the kit
which stay pretty close to the reference design for the
LM1875. They have a very simple signal path — there’s
just one capacitor and the volume control between the
input jacks and the input to the amp chip.
The build instructions are easy to follow, and the
boards themselves are great quality. Each PCB (printed
circuit board) has an eye-catching black solder mask
which is a lot more
interesting to look at than
the generic green style
you usually see. The board
uses entirely plated
through-holes which form
a strong physical and
Populating the passive
components was easy, but
it was a little finicky
getting the amp chip
mounted to the heatsink.
Nothing a pair of tweezers
and a steady hand
couldn’t deal with, though.
Post comments on this article at www.nutsvolts.com/index.php?/magazine/article/december2014_Koebel.
Figure 2. Everything held safely in place. Figure 3. Parts are well organized by function and step.
Figure 4. Amplifier components.
Figure 5. Amplifier schematic.
52 December 2014