I can personally verify this is 100% true. I used a very nice sealed pushbutton switch rated at 250V 3A from Mouser and it fused together after a few cycles. I did this despite warnings that it would do exactly that. I ended up installing a relay module.
Unfortunately, my area of expertise centers around what not to do. You can use a pushbutton with a soft-start module (relay). Here's a good place to start: https://www.diyaudio.com/community/...ains-relay-includes-soft-start-h9kpxg.354971/
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https://www.mouser.com/c/electromechanical/switches/pushbutton-switches/?contact form=SPST&mounting style=Panel Mount&series=JP&switch function=OFF - ON&instock=y
I don't know of a round, latching, illuminated, push-button switch that I'd use for full mains with typical inrush of this type of amplifier. Someone else may. I looked briefly. The switch you picked previously (I never saw a "real" spec sheet) likely would not hold up to inrush current. It was rated for 3A, but the switch sees current higher than that for brief periods every time it is turned on, and it may not be very conservatively rated. See Mark's charts of inrush current even when the ICL is in place for a typical amp. So... it will fuse. ZM and maltboy1 have said that the switch (or similar) will not last long. That's my guess as to why. I am new to electronics also. We all have to learn. I could be wrong.
I chose this one b/c of the 10A rating + TV rating for inrush current. It also has a really interesting design to break a light weld if it fuses. There could be other switches someone can recommend, but this one looks like it would last a lifetime. I'd still have a smarter person than me review the spec sheet just to be sure. I also do not know your country's electrical code. This is just an idea/example of what I think a good push-button mains-rated switch for an amp could look like. I don't know if your country requires switching of live and neutral as an example.
With your knowledge, my strongest recommendation is to build it as the guide shows (adjusted for your mains voltage) and use only the back panel switch. Once you know a little more, you can modify your project any way you like. A lot of people like the H9KPXG (link above), but I am not sure you're ready to wire and use one.
Mostly..... have fun. You will love the amp.
PS - If you promise to wait and just use the back panel switch until you are ready, I will send you a fully built H9KPXG for only the cost of postage. You only need to show me your completed amp and that you have the knowledge to add the board and wire it properly. You would need to buy the switch of your choice to work with it.
my
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Nice switch!
The worst case scenario is turning the amp on whilst the NTC is hot, e.g. you turn the amp off and then immediately realise that you made a mistake, and then turn the amp on again.
The worst thing for switch contacts is probably turning the amp off.... that would cause a sudden back EMF that would discharge across the switch contacts.... a typical switch off of an inductive load scenario. I haven't seen any mitigation efforts done so far on these forums... like placing a cap and a resistor in series, across the switch contacts (L and N) to snub and burn that energy.... obviously not an issue.
I chose a shaffner blockshutter IEC block with an EMI filter, 250V / 4A. I replace the whole block every 2 years purely as a precautionary measure.
Nevertheless, that switch looks really good and it does seem true that it'd last forever, good find!. My only concern would be the need for metalwork (ahh the horror) to accommodate the snap-in installation.
The worst case scenario is turning the amp on whilst the NTC is hot, e.g. you turn the amp off and then immediately realise that you made a mistake, and then turn the amp on again.
The worst thing for switch contacts is probably turning the amp off.... that would cause a sudden back EMF that would discharge across the switch contacts.... a typical switch off of an inductive load scenario. I haven't seen any mitigation efforts done so far on these forums... like placing a cap and a resistor in series, across the switch contacts (L and N) to snub and burn that energy.... obviously not an issue.
I chose a shaffner block
Nevertheless, that switch looks really good and it does seem true that it'd last forever, good find!. My only concern would be the need for metalwork (ahh the horror) to accommodate the snap-in installation.
^ Thank you for taking a look!
I didn't look very long to see if they or other companies had any switches in the same category / of the same type that were not snap-in. I agree re: the potential work for a clean install.
Thank you for elaborating on the turn-off behavior. Much appreciated.
The only thing I've seen similar to your description for possible mitigation (minus the resistor) is the mains rated cap across the live / neutral in the schematics for the First Watt and similar PSUs. When people have asked in the past, it's been said to be for mains HF noise filtering and spark suppression. I can't confirm whether that's accurate, only that I've copied and pasted that into my notes re: its purpose. I admit to mimicking others when in doubt, so it's in all my amps...
Cheers
I didn't look very long to see if they or other companies had any switches in the same category / of the same type that were not snap-in. I agree re: the potential work for a clean install.
Thank you for elaborating on the turn-off behavior. Much appreciated.
The only thing I've seen similar to your description for possible mitigation (minus the resistor) is the mains rated cap across the live / neutral in the schematics for the First Watt and similar PSUs. When people have asked in the past, it's been said to be for mains HF noise filtering and spark suppression. I can't confirm whether that's accurate, only that I've copied and pasted that into my notes re: its purpose. I admit to mimicking others when in doubt, so it's in all my amps... Cheers
Now that I have moved the aleph j into my office, it’s pretty close to my head (arms length) the slight buzz from the transformer and or power supply is a little annoying. It’s not a hum, it’s a buzz and there is nothing coming out of my speakers. I used to have some hum, but with some rearranging of things, thank you Ben Mah, that is gone.
I don’t want to make a huge deal about it, I just want to be sure nothing is damaged or on its way to being damaged.
I don’t want to make a huge deal about it, I just want to be sure nothing is damaged or on its way to being damaged.
A "soft-start" is a good idea regardless of whether you use an additional switch or not. Look up Inrush Current Limiter.
The Aleph J already has a "soft-start". You asked about it several posts ago, and ZM told you how to wire it properly. I think that unless you know how to add the diyAudio soft-start properly, you should not use it. It adds a new complexity to the build.
Again, I really think you will be happier / more successful if you build it like the guide shows. Then make all the modifications you want after you have a working amplifier.
The Aleph J already has a "soft-start". You asked about it several posts ago, and ZM told you how to wire it properly. I think that unless you know how to add the diyAudio soft-start properly, you should not use it. It adds a new complexity to the build.
Again, I really think you will be happier / more successful if you build it like the guide shows. Then make all the modifications you want after you have a working amplifier.
One last attempt: can a switch like this work?
https://www.audiophonics.fr/fr/inte...pole-2-positions-on-off-250v-10a-p-10904.html
https://www.audiophonics.fr/fr/inte...pole-2-positions-on-off-250v-10a-p-10904.html
While 250VAC and 10A seem reasonable, I don't feel comfortable buying an AC switch without a manufacturer's datasheet. Are you able to buy from larger suppliers like Mouser or Digikey? Since the last switch you linked to is not luminated, you might as well get a good big rocker switch as Zen Mod suggested a few pages back.
Where you put the switch is a matter of personal preference. If you are planning to use a store chassis with precut holes then it really simplify things to just stick with a switch in the back. Whereever you put the switch, just follow the setup shown in ZM's post #1084 ( https://www.diyaudio.com/community/threads/aleph-j-build-guide-for-noobs.357002/page-55#post-7469863 )
I personally find the AC wiring a little easier with the switch in the back, but some of my amps (DIY and commercial) have switches in the front and other have them in the back.
My AJ AC power switch is in the back (store chassis) and I'm ok with it.
Where you put the switch is a matter of personal preference. If you are planning to use a store chassis with precut holes then it really simplify things to just stick with a switch in the back. Whereever you put the switch, just follow the setup shown in ZM's post #1084 ( https://www.diyaudio.com/community/threads/aleph-j-build-guide-for-noobs.357002/page-55#post-7469863 )
I personally find the AC wiring a little easier with the switch in the back, but some of my amps (DIY and commercial) have switches in the front and other have them in the back.
My AJ AC power switch is in the back (store chassis) and I'm ok with it.
@neric34 - FWIW, I asked or thought a lot of the same things when building my first amps, and I still learn. You are not alone.
It's not complicated to add a switch. What you're finding is that not all "proper" switches are easy to install (particularly on a 10mm aluminum panel), "pretty", latching, or illuminated. Many came before you wanting the exact same things. Chin up! You'll find what you want. However, you may need to make a few compromises.
Good luck and have fun!
It's not complicated to add a switch. What you're finding is that not all "proper" switches are easy to install (particularly on a 10mm aluminum panel), "pretty", latching, or illuminated. Many came before you wanting the exact same things. Chin up! You'll find what you want. However, you may need to make a few compromises.
Good luck and have fun!
Is this model strong enough (and safe) ?
https://www.tme.eu/fr/details/r13-437a1-01b/commutateurs-a-levier/sci/r13-437a1-01b-hr/
Or this one is stronger :
https://www.tme.eu/fr/details/st141d00/commutateurs-a-levier/e-switch/
https://www.tme.eu/fr/details/r13-437a1-01b/commutateurs-a-levier/sci/r13-437a1-01b-hr/
Or this one is stronger :
https://www.tme.eu/fr/details/st141d00/commutateurs-a-levier/e-switch/
