After answering a question in the comment section of the Hafler DH-110 Preamplifier Refresh. I decided to design a board to hold surface mount film capacitors for capacitors C19 and C119.

I have been quite pleased with the performance of my DH-110 pre-amp with my current setup, but wanted to see what difference changing the value of the line amp input filter capacitors made.

The original filter capacitors were 0.82 uF with a 4.7K ohm series resistor fitted to a circuit board with two leads. The 0.82 uF capacitor is a surface mount type with a pair of wire leads attached which are then soldered to the traces on the back side of the single sided carrier board.
The new board accommodates a 1812 size surface mount capacitor, and a 1206 size resistor. I kept the resistor value the same, and increased the capacitor to 1.5 uF.

While I was working on the pre-amp I also changed out the power rail filter capacitors from the bi-polar versions, to some low ESR Nichicon capacitors of the same value.
After some testing and listening, I have decided that the capacitor change had little if any change on the audio range quality.
It was a fun project, but nothing magical happened. My recommendation would be to spend or save up your money for better speakers.

The board is available on OSH Park for download and ordering:
Hafler DH-110 LF Filter Rev. 1.0