Mezmerize DCB1 Building Thread

I'll post pictures when it's completed. I've also added a 21 Ohm 1% 3 watt resistor to my 10 Ohm to hot rod it a little bit more. Now the Heatsinks get warm. Spot check with temp gun reads 93*F on the Mosfets.

Thanks for all your help.
Ron
 
I have a problem, with my Mesmerize, not sure if it's a ghost, not sure what I am looking for.

Basically, when the system is powered no problem at all. I have 300mV of offset when the system is powered off. This with no connection to anything whatsoever.

The only explanation I have is that there is a capacitor trying to discharge from the output, but the funny thing is that if I shorten the output and then open it again, the 300mV come back.

I am really puzzled. It could be that I have been living with this for years.

Please let me understand.

Thanks,

Davide
 
I have a problem, with my Mesmerize, not sure if it's a ghost, not sure what I am looking for.

Basically, when the system is powered no problem at all. I have 300mV of offset when the system is powered off. This with no connection to anything whatsoever.

The only explanation I have is that there is a capacitor trying to discharge from the output, but the funny thing is that if I shorten the output and then open it again, the 300mV come back.

I am really puzzled. It could be that I have been living with this for years.

Please let me understand.

Thanks,

Davide

Maybe something with absolute ground potential? Make it be shorting to ground when off. Is it the pcb with a T arrangement on the output relay that does it already, or one older?
 
To clarify, when your PCB has this detail in double layer, the output is at ground when its powered off. And you can also confirm that with a multimeter.
 

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Long story short: I AM AN IDIOT !!!

When I assembled the PCB I did con solder all the pins of the relays, so that it would have been easier to remove them if I needed. I did not see that there was a T.

I put my speaker in danger for two years like this, I am surprise I did not destroy them.

Thanks for the help.

D.
 
Long story short: I AM AN IDIOT !!!

When I assembled the PCB I did con solder all the pins of the relays, so that it would have been easier to remove them if I needed. I did not see that there was a T.

I put my speaker in danger for two years like this, I am surprise I did not destroy them.

Thanks for the help.

D.

NOT an IDIOT!
That was good thinking, it just didn't work out this time, a learning experience for everyone.
No harm, no foul 🙂 - glad you figured it out.


Rush