Power Cables. Sound Quality Reduction under 240v

Hi

I've just invested some rather large sums of money on Aftermarket Power Cords and DIY Strip Boards.

My system comprises of the following:
1. Krell KSA 250 Amplifier
2. Audio Aero Capitole MKII CD Player
3. Supratek Sauvignon pre-amp

When I plugged the power cord into the pre-amp and used the aftermarket strip board, my wife and I immediately noticed a sudden reduction in sound quality. ie. the mid range had been instantly subdued. Furthermore, the sound seemed a little compressed with loss of detail with background piano notes.

Feeling rather upset with the sound, I then proceeded to remove the aftermarket power cable connected to the pre-amp and it with a stock standard cord. Once done, the sound quality increased, the mid-range started comming back.

Finally, I removed the DIY strip board and pluged all the components into my old $40 strip board from the local electrical shop. The sound quality improved again, back to the way it used to be. The mid range instantly returned to it's former glory with vocals having that lush sound that sounds as though the singers are right there in the room with you.

I always thought power cables where supposed to improve sound quality. Could It be that here in Australia with 240Volts, that power cords make less if not detremental difference in sound.

The Power Cord was the PSC (Pure Silver Cables) Pristine MKII

The DIY Power Strip board was made using 8 Gauge conductors, with 4 Braided and foil shield twisted together.

Any Audiophiles in Australia, If you would like to comment on your thoughts, I would be very interested.

Regards,
Clipsal