Yes, I understand and all one has to do is take a quick look at the schematic for his amplifier to get a ballpark estimation for the turn on inrush current for each amplifier. From the schematic it looks like a ballpark figure for the voltage applied to the main filter capacitors is about 60 volts and the filter capacitors are rated at 10,000 microfarads.
This tells one all that is needed to come up with an approximate value for the turn on surge current for each amplifier.
Choosing an NTC device can be a little confusing for those that are not familiar with the selection process for NTC devices, although I did see that one manufacture does have an online calculator that one can use if one understands all that is is involved.
Below is the basic math involved as you are likely aware. This example just happens to be for a resistive lamp load, but it gives the general idea. Note that the actual inrush current and its duration along with other information is needed to complete the calculations and select the best suited NTC device.
For the average person looking to do what the OP wants to do, this may be a somewhat daunting task, where as the simple selection of the correct switch may be much more simple.
It is quite likely that a 16 amp rated switch that is rated for at least 1 HP or more will take care of about 95 percent of all the needs for a high inrush current rated switch, making it fairly easy to select a switch for applications similar to the OP's.
Remember that he wants to turn on 3 amplifiers at the same time. If he does the above calculations an installs a single NTC device in his DIY switch box, it he changes his gear or decided to only use one amplifier at a time with his selected NTC device may no longer be the best device for the job.
He would need to open up his amplifiers and install an NTC device in each amplifier and not everyone is going to be comfortable doing this.
To be clear, I never said that using an NTC device is a bad thing, in fact in my previous post I said it is okay to do. But selecting the best NTC device for the job is likely to be more difficult (as seen by the calculations above) for some than just doing an interwebs search for a high surge/inrush current rated switch, which is then just basically a plug and play device it the DIY AC mains switch box.
For those of us that understand this, it seems fairly simple, but there are those that might like to do what the OP wants to do, but would struggle with the selection of the most appropriate NTC device.
BTW, you seem to be taking issue with the data that I have used, saying the information that I have provided. They are not my amplifiers and as I have already stated, I made some general estimations that should give fairly close ballpark numbers.
And in my previous post, I indicated that one can use NTC devices.
And BTW, the time to trip in general for a breaker tends follow the same general curves that fuses do. The curve below is an example for 10 and 16 amp breakers, it would be higher for higher rated breakers.
Again note the hold current when the time is in the millisecond range. The bottom horizontal line is in amps. And remember how fast, from my examples, the surge current decays.
It appears that time to clear for fuses and time to trip for breakers is not necessarily well understood.
the assertion that 3 amplifiers, rated 5 amps continuous load, will be at 80 to 100 amps inrush is rather a stretch.
Again this in not necessarily correct. Below is a simple example of what the surge current for a 10,000 microfarad capacitor with 60 volt applied to it (an estimate on my part based on the schematic diagram).
Note the initial current. This of course is a ball park number depending on the quality of the component in the power supply, but for a stout power supply this number is in the ballpark.
Again, to be clear, and I do not know how many times that I am going to have to say this, I never said that using NTC devices is a bad thing, just read my post.
But, using a high inrush current switch in the DIY switch box it is a one and done thing. All one has to do is select a switch that it rated to for at least a 1 HP electric motor (it will likely be rated for 150 amps of inrush current) and that is it. The switch box becomes basically a universal device and one does not have to open up and modify their audio gear.
Again, if one wants to open and modify their gear, then an NTC device may be okay for them.