Does Power Cord Require Burn-In To Sound Good?

Well what I think is that burn in is not enough. I put a heat strip around my power cables to maintain a minimum of 150 degrees F. If you do not do this the burn in reverts to unburn in and then you are back to square one. If you ever let your power cable temp drop below 150F the degradation to your fidelity is quite pronounced. Also you need to keep your power cables suspended above and off any hard heat absorbing surfaces. There is a tendency for the side of your heat stripped cable adjacent to the heat absorbing surface to be a bit cooler. This can cause there to be an unbalanced audio signal which can be quite distracting. Carpet is OK for a contact surface for instance where an oak floor is not. I also recommend that your heated power cable be sheltered from AC ducts in the summer for the same reason. You can never be to careful when the finest outcomes in audio are what you not only strive for but demand.

@mahlman  I put a heat strip around my power cables to maintain a minimum of 150 degrees F

 WOW! This keeps getting more bizarre all the time....Jim

This is an open ended question, as a manufacturer I know what my customers tell me.  While a quality cable will show an immediate change, burn in time will show additional changes.  It can be as short as 5 hours or as long as 100 hours.  The changes are usually in openness, bottom end and sound stage, and brightness can soften over time.  In general there is a minimum of 10 hours before you should even start to develop an opinion.  As an example, our Interconnects are all over the place in the first 50 hours, then they start to settle down and do what they are supposed to.  There are to many variables to say just how long a burn in time should be.  But that's my 2 cents...

Take a deep breath, be open, be inquisitive, hold a modest amount of skepticism with unproven assertions, be careful opening your wallet, but also question current scientific tenets and limits because life is full of experiences that are valid yet unexplainable. Many, many respected audio designers and manufacturers willingly admit that science gets an idea part of the way to reality and then listening and tweaks beyond current logic fine tune many of the finest products we love to listen to. Science, alchemy, dumb luck, and art are all relevant. Don’t kid yourself. Don’t be so rigid, to think you can no more prove than disprove. If you believe your brain and your ears can be tricked, this cuts both ways. I am more then willing to give up a portion of my fortune to be continually tricked into being so caught up in a musical performance out of my HiFi that I momentarily quit thinking about the gear and all the crap and politics coming from folks that are so full of shiit that they feel the need to defecate all over the rest of us who are just enjoying our selves. And bye the way, on my kit and with my ears, I hear warm up, burn in, settling, and all kinds of other seemingly psychedelic phenomena. Everything counts. Everything is in play. Happy Listening! [|;^)>

By jhills:  "My advice: If you bought a $5K amp and it doesn't sound good with the cord it came with, but you think supplying it with a $5K power cord will make it sound great - save your $5K and buy an amp. that has a decent power supply and sounds great with the cord it comes with....Jim."

I have to say, this is the most lucid summary on this topic.  Well stated.  

I'd like to add: buy a better amp for the difference in money when that difference is greater than 15% of the cost of the device itself, if you feel the compulsion to upgrade.  I sunk my money into the cost of the devices.  I also second:  power supply to support circuit topology and build quality.