I guess that this is explicitly aimed at those who believe that there is a such a thing as cable burn-in. If you are not one of them please feel free to move on to a different thread.
Has anyone experience of using a cable burn-in device? I am thinking of buying the Hagerman devices which a knowledgable friend recommended to me a couple of years ago and which I am belatedly considering.
Pete, that’s very diplomatic of you. 
I am in the camp that it might matter for higher level signal cables like power and speaker cables, but am less sold on low level signals, and not at all on properly-spec’ed digital interconnects. For those who are open-minded about the topic, this Enjoy the Music review of the Cable Cooker lays out some of the theory.
I did not know of the Hagerman devices but I tried and ultimately did not keep a Cable Cooker. It seemed to do what it claims to do. But in the end, I just could not see spending time with this particular part of the “ritual.” I’m a big ritual guy in general, enjoying aspects of process in wine, espresso, photography, etc., and audio. But I think this one found my boundary, especially when I encountered advocates for re-cooking cables that purportedly “revert to their raw state” over time. This is part of the value proposition of the Cable Cooker and burn-in devices in general. I do not enjoy disconnecting/swapping cables (and most reviewers complain about it), so while the box can help reviewers—a lot, I suspect—it wasn’t lining up with my enjoyment goals.
So, I found myself happily at the point where I could accomplish burn-in/brain-in* just by playing broad band music. (My inner obsessiveness demon would have to wait for the wallet-draining Vivaldi stack and multiple reference clocks.
) If you do evaluate the Hagerman, I would look forward to your comments about how it facilitates your evaluative process, or whether you think it might actually make cables better.
fn: One prospect I find very intriguing about a structured approach to burn-in and comparison of cables before and after burn-in, is that it might help tease out how important brain-in is, if at all, in this process. Instead of living/listening through the burn-in process, one’s ears and brains could conceivably more starkly compare the difference between raw and burned-in states. 
Thanks Greg. I do try wherever possible to burn-in in silence so as to avoid “Oh you just got used to it” comments. In any case sometimes the result would be that I somehow I got so used to it that it sounded worse 
.
I am with you on the pain of swapping cables - literally at my age.
Anyway the Hagerman devices seem similar in principle to the Cable Cooker albeit less costly.
It will be interesting if there are other views pasted. Meantime I have realised that If I do order them ( “them” being the interconnect and power devices and the XLR adaptor ) I will wait until after Christmas as this is a bad time of year to import things given the pre-Christmas rush.
Interesting you mention this. Both UPS and FedEx here in the States have recently triggered their shipper limit clauses in some areas due to overwhelming volume demand. It doesn’t tend to affect small scale shippers, but the reality is that this holiday season might be unprecedented from a shipping perspective.
In any case, I look forward to your evaluation.
I have just emerged from 10 days of Fedex induced mental torture: Why haven’t you sent my package? You need to pay the customs charges? How much? It’s on the invoice. You haven’t sent me an invoice. Can I pay you if I see an invoice ? Yes. Send me the invoice then. We have sent you an invoice.You haven’t sent me an invoice…etc. Eventually after 8 days they emailed me an invoice dated the same day it was emailed. So all of that stuff about having already sent it was…imaginative! Of course they will no doubt charge me warehousing for every night they kept the package.
Ugh. Thank goodness FedEx bills me in arrears for customs duties. DHL and UPS typically (for me, anyway), bill up front but make it possible to pay on line while the package is still en route.
Oh they will bill me in arrears. That invoice was only an estimate to allow them to clear the package. So there is an invoice for the balance and, I am sure another argument, yet to come.
BTW that 8 days hiatus was against a threat to return the package to the shipper if I didn’t pay within 7 days. In the future I may make shipping by FEdex a deal breaker.
So, if a cable has burned in before the invoice is paid, is it really?
I feel for the delivery companies at the moment. (Well, more for the people working at them than the entities themselves.)
But they’ve been ropey for much longer than COVID has been around. I kept switching allegiances, thinking that I’d found The One, but they all make mistakes. It’s the things that aren’t mistakes that really bother me, though.
Things like:
)Eventually things work out, but it doesn’t half add wrinkles and stress. Hope you make some headway, Pete!
Pete, why not let it burn in naturally, in its permanent place? 
A fair question but two reasons. The first is a combination of my personal indolence and the time taken with burn-in when trying to make up one’s mind. Is this an unsuitable cable or have I simply not been burning it in long enough? Some cables seem not to require much burn-in at all. For others ( e.g. what I am trying now) take far longer in situ than the typical 24 or 48 hours recommended for burn-in device sessions.
The second is that users have reported that, even after having had a cable installed for a number of years, a session with the burn-in device still brought further improvement. Well that’s just their opinion of course. However it is one reason why I am asking for reports of actual experience.