Threshold S/500 II power cord suggestions?

How reasonable is reasonable? If you are handy with an iron, you may want to try one of the kits from Chris VenHaus at VenHaus audio, Ernie Menier (plug ernie into the Audiogon search feature) or cryoparts.

Unsound-I have a Xindak FP-Gold powercord I used on my Threshold.
It really made it sound like a more powerful amp.
Improved bass was the best part.
Xindak makes very good cables at different price rangers.The FP Gold goes for $150 with $10 shipping.
Check out www.nysound.com for the best prices and 3 day shipping from China.
Knowing you though,you may not want to buy from China.But I dont mind.

Thanks for all the responses.
Thorman I'm troubled by a kind of ghosting,ringing unwanted harmonic that it is especially noticiable right smack in the middle of the treble region. This amps seems to be very sensitive to cable connections and such.
Viridian, I will look into VenHaus and Menier, thanks.
David, lest anyone get the wrong idea, the note book I'm keying this on was made in China. I was once burnt on some investments I made in Canada. Since then I prefer to do businees with companies that have a legal presence in the USA.

Wow, from your description of the sound, it almost seems that your amp is unstable and going into ringing. You may just want to look at some simple waveforms on a scope, if you have any friends that have one, to see if it is misbehaving. The Threshold should really be quite invarient regarding load resistance and capacitance.

Unsound: Can't help you with the ringing issue.Never had a hint of problen with the S/300 for about 8 years or so. You may have other issues here.