As IB says, if you know what you are doing and can get at everything easily, you don’t need to turn things off for many cable unplugs.
Anyone who has watched Jason swapping things during a Naim demo can confirm that mostly he doesn’t turn things off and he doesn’t get buzzes and bangs as he works.
But if you are at all uncertain, or it’s hard to get at, then turning off the power on all the relevant units makes sure that you don’t get a nasty and potentially expensive surprise.
Not everybody knows what they’re doing, but a lot of people think they know what they’re doing.
When I swap cables, I do so without being able to see the sockets at the rear of the amp. I suspect this is very common.
If the centre pin of an RCA plug touched the outer ring of an RCA socket when both are powered, would muting or turning down volume prevent possible damage.
If you have an easy access to the rear of your rack, I agree with you. Otherwise, to be absolutely safe, better turn off the preamp. At least it’s what I prefer to do.
If the centre pin of an RCA plug touched the outer ring of an RCA socket when both are powered, would muting or turning down volume prevent possible damage.
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So shorting out the output of whatever you are connecting to the pre-amp won’t cause any damage.
If the preamp is muted no audio signal can get to the power amp or speakers so you can pretty much do what you like. Something like a Stageline powered by the powered Aux 2 socket is different and in that case the power supply should be turned off before connections are made.
I have never encountered a preamp or source component (particularly those with RCA connectors), where the output impedance is low enough as to overload the output stage sufficiently to cause damage, particularly for the sort of short term casual contact you get when you miss trying to connect a cable.
I would doubt that even a long term short on the output would do any damage to the vast majority of source components or preamps (but there could be some exceptions here).
That’s because the power supply is transmitted through the same connector as the signal.
It’s the plugging or unplugging of the power connection that is of concern such cases.
I’m going to work with muting to unplug but powering down to reconnect as I don’t trust the combination of my sight and underdeveloped motor skills on the latter.
A few updates. Had an email to confirm no issue with the Hi-Line. No surprise after last night. They mused that instinctively they’d suggest amp. I’d be very disappointed if that were the case having had a full repair from Naim not so long ago.
Interestingly the sibilance I detected last night reminds me very much of comments by Mark Raggett about it needing a recap. Again, far too soon but given that the TV sound quality is perhaps a little short of where I’ve heard it, albeit not as dramatic, I’m inclined to keep that as low down the list for now.
The amp musing induced some panic that maybe things have somehow been wrongly connected again, but this time by me. Pulled up the online manuals and gently fumbled behind the Hutter (a whole thread and no-one has blamed the shelves or the Powerigel. Most disappointing :))
I think all is well although I did have a small panic thinking “Hang on. The HC2 DR is getting power from the 200 and the mains but that doesn’t seem possible as the connection between the two boxes is explicitly stated to be passive.”
However, casting my mind back it did remind me that there has been one other change much earlier this year when @Richard.Dane suggested my Burndy could be backwards after my having posted a photo. I could never see the markings but took the advice and reversed. I can’t say there was any noticeable uplift at all but could it have triggered an issue?
Anyway, Sky box out tomorrow night and we’ll see what happens.
It’s been a rewarding week in some other ways and I’m taking tentative steps to thinking about this a lot more. Wondering about re-checking the cables at the speaker end. My assumption is that also doesn’t need a power down?
Mike - good to hear things are going in the right direction. It depends what you mean regarding re-checking cables at the speaker end. If it’s just a visual check then no need to power down - if it’s anything more, checking tightness, disconnecting etc then power off the 200 first just to save any accidents if connector pins were to touch.
Yes, pulling out, opening up the Naim connectors and checking everything is where it should be. So, will do that when I power down to re-insert the Hi-Kine. That will then deal with the perennial “it’s out of phase” issue. I know it isn’t (lost track of how many times it’s been checked but it’s another one for the flailets to tick off
You should be able to feel a band at the source end of the Burndy. From memory, about 1/2" wide and three or four inches down from the knurled locking collar.
As you one by one make changes to troubleshoot this you could also temporarily take the Hicap DR out of the system, powering the pre from the NAP 200. This would help eliminate the Hicap from the equation.
From memory when I upgraded from 202/200 to 202/Hicap/200 the balance was similar, but with more insight. If there’s something wrong with the Hicap things should improve with it powered by the Nap 200.
Thank you. Fear not. The Burndy is the right way round following that advice from @Richard.Dane. I suppose the question then is whether it previously not being could have done some damage?
Going to unplug the Sky box later tonight as suggested below. Struck me as credible from the point of view of variability.
Play some music tonight after taking the Sky box out. Do the same tomorrow morning before going to watch the boy play rugby and then again afterwards before heading into Manchester to take the lavender back and reclaim my HL.
When I power down to insert the Sky and the HL (powering down for the reasons set out previously) tomorrow evening (assuming of course that the Sky doesn’t reveal itself as the issue) I’m going to take the speaker cables out at the 200 end; bring them out to the middle of the living room; ensure we’re in phase and then (likely with Mrs. H. eyes) check what’s going on inside the Naim connectors and at the speaker end.
After that I think we’re down to boxes unless some Snaics have developed some weird issue. Do Snaics do that? Easy enough to take the XPS2 out of the question at some point and that just leaves a Burndy (again) or the amplification. Would like to think it’s not a 5 year old HC2 DR or a 200 that had a full service/repair but, yes, you’re right, I am still pretty naffed off with the whole thing but slowly coming back to engaging with solutions.
Incidentally, although things were poor beforehand we had a power cut for 10 minutes a week or so back so the whole system went off and then came back simultaneously. Chances of that impacting further?