The NRG-5 is an older cable and is no longer made.
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The problem with the Rotel Class D is likely because of the switching power supply they use. Also, not all Class D circuits are the same or act the same. If you are interested in getting a Class D solution, the ATI amplifiers (AT52x and AT54x) are much better designs that use a full linear power supply and the latest "nCore" amp board technology. There are other manufacturers as well. My impressions of Class D is that the amp can sound extremely clean with excellent separation of insturments and clarity. However, it lacks that very high frequency resolution or "air" that adds life to the music. Many people love their Class D amps, but I prefer the Class AB type.
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I think Audioquest cables are pretty decent because they all use a 21awg solid core conductor. I think 20awg is the sweet spot, but 21awg is just fine. You then have to look at how good of copper you want and what kind of terminations (either gold-plated or silver-plated). The more expensive models have the DBS battery thing which I have never tested. Wire World also has very excellent cables.
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For Toslink, don't even try to use them because the are the worst digital transfer, but if you absolutely have to , Lifatec cables are the best for the money.
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For digital COAX, if you are on a budget, get the Beldon 1694A from Blue Jeans cables and minimum 6 feet for any digital cable. If you have money, then spend $230 or so on DH Labs D-750 cable. Or somewhere in between with an Audioquest digital COAX. For USB/Cat6, I don't know, but I do know that silver or pure silver is the best for any digital cable.
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The problem with the Rotel Class D is likely because of the switching power supply they use. Also, not all Class D circuits are the same or act the same. If you are interested in getting a Class D solution, the ATI amplifiers (AT52x and AT54x) are much better designs that use a full linear power supply and the latest "nCore" amp board technology. There are other manufacturers as well. My impressions of Class D is that the amp can sound extremely clean with excellent separation of insturments and clarity. However, it lacks that very high frequency resolution or "air" that adds life to the music. Many people love their Class D amps, but I prefer the Class AB type.
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I think Audioquest cables are pretty decent because they all use a 21awg solid core conductor. I think 20awg is the sweet spot, but 21awg is just fine. You then have to look at how good of copper you want and what kind of terminations (either gold-plated or silver-plated). The more expensive models have the DBS battery thing which I have never tested. Wire World also has very excellent cables.
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For Toslink, don't even try to use them because the are the worst digital transfer, but if you absolutely have to , Lifatec cables are the best for the money.
----
For digital COAX, if you are on a budget, get the Beldon 1694A from Blue Jeans cables and minimum 6 feet for any digital cable. If you have money, then spend $230 or so on DH Labs D-750 cable. Or somewhere in between with an Audioquest digital COAX. For USB/Cat6, I don't know, but I do know that silver or pure silver is the best for any digital cable.