One of the worst and best things that's happened to passive components used in stereo equipment is the surface mount part. These tiny bits of silicon, plastic and metal are used to form the transistors, diodes, capacitors and resistors used in modern equipment. Before surface mount there were through hole parts and the differences between the two can be summed up simply: through hole parts have legs, surface mount do not and as a result, can be much smaller.
Here are two pictures:
The differences are obvious.
And when I first heard about surface mount they appealed to me because their lack of legs meant fewer junctions and the potential for a purer part. What I learned was not so simple.
Turns out the best choice between the two technologies depends greatly on the application they are used in. Surface mount makes products like the DirectStream DAC possible. Without the small size and direct connections the DAC would not be as good. Yet, those same small parts in the power amplifier or a preamplifier don't perform as well. And this has to do with both the amount and type of material used in them and what we are doing.
More tomorrow.
