Power cable break in?

This topic may cause a stir. But here go's. I have been experimenting with upgraded power cords moving on from my Shunyata Black Mamba's (original version) I have had about 20 years. I was thinking that surely there have been some advancements since then. Research told me to try some Wireworld Silver Electra 7's on front end digital components.  I retired 2 Black Mambas with the Silver Electra 7's on my DAC and CD Transport. I had earlier replaced an entry level Shunyata with a Electra 7 on my DDC unit. Because I just returned with my newly updated and upgraded VAC Cla 1 MK III preamp I was not sure what was doing what but it was all better sounding. Well the two new power cords did improve over time as they broke in, primarily in transient quickness, soundstage size and inner detail with a more delicate top end. But that's not the reason I am making this post. What I did next was found a Synergistic Reference Master coupler to try for a great price, it was a classic and I had found in my research that a writer from TAS had one on his VAC Cla preamp as his reference. When it arrived I pulled my Black Mamba off the pre amp and placed this very stiff PC on. What happened next is that the music had more impact, dynamics and punch, however the bass although more pronounced as a bit too bloated and lacked the pitch definition compared to the Black Mamba. But damn the dynamics and attack were undeniable! What I want to do is stick this PC on something that is on all the time and give it some burn in time. But it's stiffness' is so far preventing that and I cannot get it angled to properly plug it into a linear power supply I have. Is it possible that this PC over some time will maybe lose the Bass bloat and settle down with better pitch definition? (I didn't really experience that type break in with the Wireworld Silver Electra 7 PC's that I remember, they kinda filled in over time)  If it does become refined than it will be a great match for the pre amp. I just don't think it's wise to leave the pre amp on all the time maybe a few days? I usually turn it on in the morning and turn it off when I am finished several hours later. Pre amp tubes have good life and I have more back ups so maybe 48-72 hours non stop so I can try. What's my chances the bloat will disappear with refinement?


I don't know if the Synergistic Reference Master coupler will lose its bloatedness and improve the pitch definition with use however you could purchase some inexpensive adapters and use the Reference Master coupler on your refrigerator for a week or so for break-in and then retry it.

@lak  Thanks I didn't know those existed, I just ordered two off Amazon. They can come in handy to break in Pc's. 👍

Prior to purchasing an Audiodharma Cable Cooker, that's how I use to break in my power cords.

I googled the Synergistic Research Master Coupler and it appears it is no longer in production.  So you bought it used?  It has thousands of hours on it.  Does time in a shipping box reset the break in period on a cable?  What should I do in handling my cabes to avoid resetting the break in period?  Is there a reset switch?


Here they come!😂

Yup! You can count on them to pollinate every single cable thread every single time 😂🤷‍♂️. But wait… there are more…


P.S: I meant to say “pollute”, not “pollinate”, but then I figured it works just as well, so I left it up there 😉

@carlsbad - In my communications with Mike Morrow related to my MA4 balanced interconnect, he said that he recommends hanging their cables when not in use as they require a minimal break-in period if stored rolled up.  The estimated time was 24-48 hours to settle in again, but not the full 400-500 hours that's recommended when new.  It makes my head hurt a bit to comprehend, but there it is.

Got it.  If you coil up your cables it take 24 to 48 hours to re-break them in.

I can’t tell you 50 hours or 500 hours, but I’ve always plugged power cords into my desktop that’s on all the time before I ever tried them into my system. No wasting tube or electricity that I wasn’t already wasting.

All the best.

I never got the refrigerator thing as a modern refrigerator does not "run" very often, but it works.

My problem was moving the fridge (out/in) in a narrow galley kitchen.

I've also successfully used vacuum cleaners and power tools in the past (with the aid of an adaptor), but now my vintage heavy duty Kirby vac's have been replaced with lightweight Dyson's, and I can't think of the last time I used a power tool (outside of a Dremel or a food processor).

Maybe a space heater set to a low setting (< 750 watts)?



Refrigerator is good for inrush current, not so much for the continuous thing. A space heater is excellent place for burn in, these things draw a lot of current and voltage.

Caution regarding using space heaters...

Mine is rated 1500 watts and it will damage a high quality 6 foot 12 gauge extension cord if run @ full power for extended periods of time (the X-cords cost more than the heater).

For this reason I run it @ half power (approx. 750 watts) and have not experienced any problems/damage doing so for the past 2 winters.

I retired the one that was run @ full power and have been using a backup/spare.

This is the heater (which works well as now used).



Meanwhile back at the Ranch, the power cord is burning in nicely. The bass bloat is gone, the dynamics remain and it is breaking nicely. Carry on.....

@fthompson251 I’d give it 24hrs. That in my experience is all a used cable needs to settle. If after 24hrs of play time you hear bloated bass, it’s what it sounds like. 

@audphile1  Yeah I got all of that now and it's good to go. Interesting how different PC's will mate with different pieces. I tripped over this pairing reading an old Absolute  Sound review. Dynamics and leading edge transient speed is invigorating my listening sessions. 

I can't comment on you particular cable but yes, cables do break in and power cables do as well. I had one of my power cables that sounded bright and upfront for the first couple hours then became dull and with bloated bass and that stayed for a while. It took a couple weeks to sound good again. And yes, cables that have been coiled may need to be broken in again to some extent - especially, I believe, if they contain silver.

I tried the pc burn like curiousjim...i believe its works just fine as on all the time.Venhaus says 2 weeks give a 95% burnin.Works for me.Its funny how all the ic and speaker cable jockying has given way to power cables and higher end connectors for me.You know that upstream thing....enjoy journey ft251

That’s funny OP “here they come😂”. I’ve never understood how many do no here break in. I can move cables around without even disconnecting them and find I lose bass for hours or a day or 2. Disconnecting and storing then hooking them up again is even worse. The worst was breaking in Furatech NCF outlets. Anyone doesn’t believe in break in buy a NCF outlet and tell me what you hear.

This is a serious question, not sarcasm:  if a power cable requires breaking, doesn't it stand to reason that brand new Romex in a brand new circuit would also need break in time?


The difference between Romex and audio cables is the insulation. Romex uses PVC (Polyvinyl Chloride) with a nylon jacket. Cables utilize a dielectric, or electrical insulator that is polarized by an applied electrical field.

Dielectric material varies in what results you will have, but it acts like a battery, in that when you send data or music via a cable that is polarized, the dielectric builds up a charge. Which is why some mfg - like AQ - add an actual battery, which places a DC voltage on the insulator itself, forcing it to remain charged in one direction only.

Power cable insulation (dielectric material) provides high polarizability. Creating an electric field which is called an "electric dipole moment". This means that the elementary particles (protons and electrons) are electrified; generally a molecular orientation that is active until it, well...it’s not. Timeline’s vary because not all cables are made of the same dielectric(s) and some are coated with other metals (think silver on copper) which, again, creates polarization curves. The shifting of these protons and electrons is the activity that settles over time. That is what you are hearing.

So, no, Romex does not need time to settle because there are no dielectrics being used in the insulation of the metals.

Hope this helps!