Core Power TechnologiesDiamond Xtreme 6 foot PC-World Class cordsnewCore Power Technologies Diamond Xtreme 15 or 20 amp hi current power cordAsk us about 6 Mo. No Interest thru PayPal Worldwide FREE Freight MARCH MADNESS SALE At Underwood we looked for two years looking for the right cable supplier. We finally found ...649.00

Core Power Technologies Diamond Xtreme 15 or 20 amp hi current power cord [Expired]

no longer for sale

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At Underwood we looked for two years looking for the right cable supplier. We finally found the source that makes cable for much of the industry. Our power cables are sold by other manufacturers for 3-10 times our retails. We sell them Internet Direct with low overhead and no dealer profits in an attempt to bring some sanity to the cable business.

The $1500.00 Diamond Xtreme uses more of the material as the $1000.00 Diamond and is designed for high and ultra high current devices. It uses 18 separate cores of 16 gauge 8N OFC copper plated with 70 microns of extruded pure silver. It is insulated with FEP Teflon. The custom weave we use is optimized for maximum performance, ie, inductance and capacitance. State of the art carbon fiber IEC power plugs are used. It is available in 20 amp or 15 amp versions. Add $100.00 for the 20 amp version. Both have 15 amp wall plugs.

   We have them in both 15 and 20 amp IEC’s.

15 amp cords are on sale for 649.00

20 amp cords are on sale for $699.00

ln the Tone Audio review of the standard Diamond cord they said:
"In keeping with the current world situation, I commend Core Power for offering a major deal at a time like this to keep you all rocking. I suspect that if you audition one in your system, with familiar music, you’ll want to keep it. We’re keeping the review sample and purchasing a few more."

See the entire Tone audio review at:

Positive Feedback said of the Diamond cord:

"Am I keeping the Diamond Power Cord? I am. I think it is well built and when I look at the other power cables I have on hand, it clearly is built better than anything I have seen under anywhere near its price point.

"The Diamond Power Cord gets my recommendation if you are a believer that after market power cords make a real difference. If you do, go try one, I think you will likely end up keeping it."

The 6 foot Diamond Xtreme retails at $1600.00 in 20 amp form and $1500.00 with 15 amp IEC. we also have them in 1m length.

Here is some customer feedback on our new cable line:

1) Aloha Walter, I received the Deep Core and more recently received the Core Diamond AC cable.  Today, I received the receipt - thank you. I could not wait, I connected the Deep Core to the wall via the Diamond AC cable and turned the system back on.  I played music.  Wow!   The outstanding system I had before became even better.  Deeper more detailed bass was my initial response.  After a while a female vocalist began singing and I was drawn into the room where the system resides.  Incredible detail and vocal nuances became evident in such intimate detail.  My system sounded good before but now, Grandiose!!!!

2) By the way, the 8 foot pair of the Core Power speaker cables I purchased from you are the best I have ever heard on my system, mirroring the same high quality as your other Deep Core products.  They have transformed my system from very good to magical!
Thanks for everything and your professional mannerism and expertice,    JS

3) Wally, Yet another "Oh My Goodness", what have I been missing all these long years!
I thought the Mac 601 mono-blocks were just hyped old tech with pretty blue dials. After getting the new Diamond Xtreme cords, it was as if a window opened and the heavy curtains were pulled back, and the sun, the birds, the whisper of the wind in the leaves, and the neighbors arguing 4 blocks away could now be heard in extreme detail. What I difference!  Really, really big change. Its like taking the cotton out of your ears and hearing why you spent so much $$$$ on this addiction in the first place.  Like audio heroin!  
I’m glad I’ve already paid for my daughter’s education!
And, all this time I thought I knew what good stereo was.  I’m already in audio heaven!  How much better do it get?   Bruce S.

4) Walter, These Gold power cables are great and not just for the price.   I put one in the office system and was blown away so i replaced the $1000 dollar one on the Mcintosh in the main system and the Core is better.   I will try the interconnects this week.    Thanks, Rick
5) Walter, I have been in this hobby since 1970 and a dealer for certain products since the late 1990’s. I have had many different power cords with great results, but I never thought I could get the performance that are offered by your cords at the prices you offer. I feel they are equal to cords costing at least 5 or more times. I have not had the opportunity to try all that is out there and could not afford some even at dealer pricing. I have done preliminary listening with all of your cords in my system and I am utterly amazed. I do not know how you do it, but I am a believer. At this point I do not need to go to any other cords. Cannot wait to hear what the Equi=Core and Deep=Core will offer. I will talk to my customers and local audio friends. Deryl
6) “I swapped my Nordost Baldur for the Power Core Diamond Speaker cable about three weeks ago.  I try to take note of my equipment performance (for my own memory) - this is the first time I send an email with my notes to someone else. I thought Walter deserved it.  I had the Nordost for the last 10 years, after a love affair with Audioquest. I tried cables from other brands but ultimately went back to the Baldur. My system is comprised of Sonus Faber Guarnieri, two subs Syzygy 10”, Odyssey Stratos Monoblocks SE, PS Audio PW DAC and Transport and Bluesound Node 2i. I spend
money wisely - I have three teenager kids and college is looming ahead.  For example, I
kept the SF Guarnieri for over 20 years, because all my listening sessions with other speakers did not bring substantial improvements unless I would have to spend two-three times what I had spent on the SF.  I love music, but I avoid spending money for what I would only consider “marginal improvements”.
In come the Diamond Speaker Cables.  I bought them at about half the price of what I had spent on my Baldurs years back - Walter’s claim of providing a high multiple of their value tempted me.
Once swapped I was hit by initial strong microdinamics that impressed me (in my definition: ability in the reproduction of music to change rapidly to changes in the recorded performance tone, e.g. going from PPP to FF and viceversa), but the sense of stage width and depth was not better than my Baldurs, nor was I convincer of details retrieval.  I swapped back to the Baldurs, which confirmed my initial impressions.  I decided to persevere and let the Diamond break in for two weeks.  This weekend I gave it a serious listen:
Microdynamics were better than the Baldur’s - confirming my initial impression - but now: details pulled out much more vividly than the original listen, most importantly, there was an overall sense of presence and scale that took me to a heightened level of performance.  No matter what the music. Billie Eilish “was in the room” with her young sultry/rasping voice, Pink FLoyd Wish you Were Here guitar attack popped out from the center right of the soundstage, the dynamics of Bach’s Goldberg Variations were more present and “lifelike” - one step closer to a real close up performance - Gould was humming along passionately.  The 2nd movement of Abbado’s Van B’s 3rd symphony was more present than I heard before in my system, the sense of scale of the orchestra was stretching outside the back wall of my listening room.  Enough said.  Can a cable make such a difference in a system?  It did in mine.  I am keeping the Diamond and my Baldur’s will soon hit e-bay - anybody’s interested?”   Angelo
7) Walter, These Core Power power cables are great and not just for the price.   I put one in the office system and was blown away so i replaced the $1000 dollar one on the Mcintosh in the main system and the Core is better.   I will try the interconnects this week.  Rick

8) Walter, just a few words on the C/P Diamonds.  I now have 2 Diamond Power Cables, and 1 Diamond XLR Interconnect. I will be buying more!  As you have said, they are THE BEST.  Nothing but music, black background, WIDE--TALL--DEEP soundstage. Treble, bass, and mids are perfect!  Layering 2 die 4!
I am hearing technicolor sound like never before! Each additional cable has been like an expensive upgrade in hardware.  And their ability to convey the emotion of the music is magical.  Just one final note...I had been using some (HFC) High Fidelity Cables, ridiculously priced, you know, the ones with the silly-ass magnets?  Core Power Diamonds crushed ’em.  Now I feel like a dummy having wasted my money on them---NEVER AGAIN.  From now on its Core Power, baby, YOU BETCHA! Thank you, Walter, for bringing out another sensational deal.

9) Hi Walter, Thank you.
I’ve been thinking that needs to be said. The past few of days have been a new step up in my listening experience, and are very much in line with what I’ve been pursuing for years and years with one upgrade after another. With the Equi=Core and Diamond power cables, the really telling part is how much clarity there is even at the very lowest levels of listening; there’s real bass coming from my 15” woofers at whisper-quiet levels! And of course there’s even greater detail when the volume is higher. Yesterday I stopped in my tracks when a classical harp piece was playing and between movements I heard the harpist’s feet change pedals. Stunning.
I have absolutely no idea how upgrading the power feed to my system can have such a dramatic effect on the quality of the sound, but there’s no denying what my wife and I are both hearing.
As I ponder that while we both sit wordlessly stuck in our seats listening to one piece of music after another, I realize it’s because of you and what a remarkable business you have. Your passion for great sound is obvious, but also how much you want to share it with everyone possible by making it as affordable as possible. Your website features brands I’ve only seen mentioned in the high-end audio press, or that I’ve never heard of, but all of which are clearly top-notch in the world of audio, at price points that are much more accessible to those of us who might not be as well-heeled as others. Emerald Physics? Wyred4Sound? Deep=Core? Wywires? Wireworld cables? I certainly would have never known any of these first-hand without Underwood Hi-Fi.
I know that I could have put together a pretty good system from other vendors, both local and online, but to get to where we are now would easily cost double or triple what you charge. And for that I thank you.
Oftentimes in the world of business too many good things are treated as expected, and not recognized for how good they really are. I felt this is my opportunity to rectify that at least just this once, and to let you know how much I appreciate you and your company.
Cheers, Daniel
10) Finally got round to trying the Gold power cables and I gotta say they are are amazing. Mind thoroughly blown! I might have to find some cash for a few more.  Pierre

International sales outside of the US and Canada are only paid with PayPal or wire transfer.

We accept PayPal, Visa, AMEX, Discover, MasterCard, bank wires & money orders.  Read our over 13,700 points of AudiogoN #1 rated feedback and then call 770-667-5633 with questions or to order these fine power cord and any other Core Power cables that are all on sale. 

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Typical ship time from order is 1 day.

Brands carried: Audio Alchemy, Audio GD electronics, Audio GE speakers, Black Ice tube electronics, Bluesound music streamers and servers, Bob Carver tube amplifiers, Core Power Technologies A/V power conditioners and cables, DSPeaker room correction, EAT Turntables, Emerald Physics speakers & amplifiers, Focal headphones, HifiMan headphones, Iso-Acoustics, LSA speakers, turntables, headphones & electronics, Marantz Reference, Martin Logan speakers & subwoofers, Melco servers, Mofi Electronics, Musical Fidelity, Music Hall, Ortofon cartridges, Peachtree Audio, Project turntables, Quad, Raal-Requisite headphones, Sendy headphones, Silverline Audio speakers, SPL Electronics, Sumiko cartridges, Sweet Vinyl pop & click filters, Wireworld, Wywires, Zesto Audio tube electronics

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member since July 2000

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