Do I need upgraded power cables?

The first thing that I would replace are the stock power cables for the SVS subwoofers. Audioquest, Shunyata and Audience have some affordable choices that make a big difference over the stock cord. Make sure any amplifiers are plugged directly into the wall outlets because any power conditioner will limit current to them. It's okay to plug source components into the conditioner.

Wow, I am grateful for all the responses. A big thank you to all! I don't understand not using a power conditioner with an amp. I would have guessed that conditioned power would be good for it. Do amps not need conditioning? Thanks 

@wofford 

I will leave you with this, sea salt tastes different than mineral salt, and pink salt tastes different still!  They are all salt!

They are all mainly salt.  None is 100% pure sodium chloride which is what we mainly think of as salt. The chemical differences account for the difference in taste, and the difference in colour.  Sea water today has about 1 part magnesium for every 10 parts sodium, and even more sulphate per chloride ion.

Mineral (rock) salt and pink (Himalayan) salt were deposited when the sea chemistry was a bit different.  Himalayan salt mainly comes from Pakistan quite a long way from the mountains.

You can taste a difference which is reflected in measurable difference in composition and even crystal size!  The hysteria from health gurus around the merits of various salts does have a familiar ring to me ...

@bzawa 

I don't understand not using a power conditioner with an amp. I would have guessed that conditioned power would be good for it. Do amps not need conditioning?

All mains-driven amplifiers convert incoming Alternating Current (AC) to Direct Current (DC) to power their internal power supply rails, which operate at a different voltage.  The normal arrangement is a hefty voltage transformer followed by a bridge rectifier, with the output smoothed by huge capacitors.  In general, the more expensive the amplifier, the beefier these components are and the less the impact of AC variations on the DC rail voltage.

Out of all your electronic components, an expensive power amplifier is likely to benefit least from power conditioning, especially if the power conditioner is wimpy, in my opinion!  I also think most electrical noise is generated by your own components ...

@richardbrand +1 on "an expensive power amplifier is likely to benefit least from power conditioning”

in analog design requirements, more noise / ripple / drops in the AC power requires more circuitry, higher cost components, etc., to isolate “non ideal” AC power issues from sound..