Isolation switches for speakers (in-amp and elsewhere)

Hi folks :slight_smile:

I have been using Arcam amps (from the 90s, nice neutral sound and very reliable), and each one has a switch on the front to isolate the speakers - it’s for a “second” set but the logic is you use the first set if you don’t want speaker isolation switch or the second set if you do.

I am in the process of moving to Quad amps (a 306 and a 520F at the moment), which have no speaker isolation switches.

(They also have no level control which is another complaint but I’ll save that for another thread maybe).

What are folks thoughts on this?

I use the switches to isolate whenever I go to bed, or leave the room for a significant amount of time.
Also very useful when plugging/unplugging of course, nothing worse than a power amp at full gain (because it doesn’t have level controls!!!) and an rca connector being swapped.

I could modify the Quads (don’t want to make them non-standard), I could build an external switch or relay box to do the job, or I could ignore it and put up with switch on thump (low level so not a worry) and the concern of an amp going bad whilst I’m away from them or asleep and frying a woofer (unlikely but still something I obsess about, which is probab;y why I have never had it happen), AND have to power down power amps whenever I make a change to connections (happens at least weekly at the moment, sometimes hourly.

I couldn’t afford to replace blown speakers, and most of my speakers have irreplaceable drivers anyway.

Remove speaker leads from the power amplifier.

aye but fiddly doing it every time i go to sleep (3 times a day usually).
less intrusive to the signal path than switches and relays though, and would “contact clean” each time :slight_smile:

John, you think (worry) too much… How often does a power amp go DC! I leave all my equipment powered 24/7, and I have for years, never had a problem. It could just as easily go bang with constant power cycling. If my equipment should ever go south I just pull out one of my many reserves and I’m back on track. Turn your power amp through 180 degrees and pull the + lead if your neurosis is that severe, has the better of you. It’s like when my SUV was wrecked by a deer running into my vehicle, I didn’t think for a second it may happen again, or consider not driving the same stretch of road ever again…schitt happens but not that often. That’s just my persona. Obviously, I cannot comment on your mental fragility… :face_with_head_bandage: :grin:

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Hmm, now that could be the solution (and I should mark it as such) :slight_smile:

I’m not weeping or shaking at the thought of an amp going DC, but I do seem to be trying to prepare for the worst a lot.

I think my problem is, for the last 20 years I was working in a job that required me to imagine every possible thing that could go wrong with a technical system, and mitigate against it thus allowing 24/7 operation, you know the kind of thing, multiple redundant servers each with multiple redundant power supplies, disks, network connections etc. etc. ad nauseam.

So the question I should have asked is “has anyone had an amp go DC on them?”, and, as I suspect now, the answer is pretty much no one, then I can chill.

They do stay on most of the time now, switched off once or twice a week at most (when not being swapped around etc.) :slight_smile:

Now you have me worried about my son. He is a process safety engineer. I wonder what would happen to him in 20 years!

Disasters happen when I play around with cables, be they power, interconnects or speaker cables when anything is on. Normal operation is sweet and safe.

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It’s a difficult habit to break, for sure.

I imagine Health and Safety inspectors have difficulty when going to a restaurant too :wink:

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I agree.

Son is doing dairy processing factories for the next 12 months. So, it’s both public health and plant staff safety.

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Hi Jona
I use a Luxman AS-55 as a switch between my 3 different amps and 1 set of speakers.
If at least one of the amps is off, it’s basically like disconnecting the speakers.
You can find a used one for a few hundreds dollars.image


So to sum up:

2 or 3 votes of “chill man it ain’t gonna happen and in the unlikely event it will it will only happen once”

1 suggestion of mental frailty :wink:
1 “gosh I hope my son doesn’t turn out like you” :wink:
1 speaker switch suggestion (appreciated!)

I shall just leave ‘em plugged in and think about it no more!

Thanks all :slight_smile:


Aye, you can’t be wrong with that.

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