Threshold S/500 II power cord suggestions?


I never really believed power cords could make much of a difference until I got this amp. Proper "dressing" of the power cord made significant differnces. Now I'm wondering if can improve upon it further. I'm hoping to keep the costs reasonable. Any suggestions?
unsound
I am using a magic cord power cable from Signal Cable on my Threshold S350e with good results. Inexpensive and maybe worth a try.
Its really subtle. Perhaps my choice of words is too strong. Most noticable on female voice where the singer just gets past normal voice to extend into that stronger but oh so feminine fequency and by some of the sharper high notes on piano. In both case there is a touch of this glare, a tiny bit of brightness. One really has to listen to hear it elsewhere. Extreme high freqeuncies like cymbals and triangles are beautifully delicate and shimmering. The bass is extended, powerfull, rich and tight. The midrange is natural with no undue chestiness. Soundstage is wide, high and deep. Performers have space all around. Other than the one issue I've mentioned everything seemlessly integrates. If I can fix this sublte issue, I'll be very happy indeed. By moving some things away from the amps, tightening everything from drivers on baffles and RCA's on interconnects and components, to dressing the power cord, its all but dissappeard. The amp has recently been gone over by Jon Soderberg, so I have good reason to believe its behaving as it should. This amp doesn't like to be shut off either! The amp is a good case for the problems inherent in double blind "shoot outs". It takes time for it to warm up and be its best, even after just a brief rest.
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.
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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.
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I guess it really depends on what your trying to change.There are many cords that'll work. I used a Discovery cord on my S/300 and it added a touch of warmth and worked real well. If you want to stay neutral with plenty of slam I would suggest the VH Audio flavor 4 cords.
Good Luck , I do have a 2 meter Discovery cord if you wish to try it.It is a touch warm though and it may or maynot be what your looking for...Goog Luck
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.