Definitive Technology Mythos STS auto power on not working properly

Mine was like that too, until I needed to crank my main amp so much that it switched off . Than the amp in the speaker stoped switching on completely after a while.
So you had to change just that one cap and now the sensitivity is back to how it was? That's excellent info, I will do this when the problem worsens.

Can you share the exact capacitor info so I can order them ahead of time?
 
That's what helped with mine...
All those small caps are ****. Also easy to damage the board tracks when desoldering them. Be careful. The new one is much bigger
 

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A normal longer Philips screwdriver and allen key for the stand.
Remove the stand, than the bottom where the power cord is plugged in. The transformer is attached to it. Disconnect it from the board. Than the 4 screws which hold the lower passive radiator and remove it. Than you have acces to the amp. It's held in place by another 4 screws and you will need to disconnect all the wire connectors that go in it and be careful with them, because they are glued. You may use a small flat screwdriver to help you. Than you can take it out.

I believe there is a yt video showing how to change an amp so there you can see it too.
 
Hello, I installed all the transistors the same as they were, I repeat, carefully check all the passive elements on the boards and check the soldering (resistors, capacitors, check their values), the quality of the SMD resistors is very poor. I don’t see the point in changing everything indiscriminately; many people change capacitors based on power supply, but in my opinion this is a useless exercise. And an instruction for all owners of Mythos ST
acoustics - do not leave them constantly connected to the power supply, since the entire circuit is in operation all the time and there is no switch there, only the signal of the audio path is muffled.
 
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I see many of the same capacitors (VT 10 16V) on the board. If the ones controlling the audio sensing circuit have gone bad (and these are probably the only ones that really result in an obvious issue), wouldn't it be a good idea to replace at least all of the same capacitors? Maybe even other capacitors on the board with some higher quality ones?

I'm going to open mine up and want to know what caps to buy before I do. Are these correct replacements? https://www.aliexpress.us/item/2251832629693676.html?gatewayAdapt=glo2usa4itemAdapt
 
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I changed some with better ones with the same parameters but they are physically much bigger.

Also very important is that removing the old ones is tricky, because the board is **** and for every changed one you risk damaging the circuits in layed on the boardm be carefully.
 
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