Hello Whitesnake, I have a ML 23.5 with the boards very repaired and they are no longer in good shape, I seem to remember that something was not right in a channel and the protection was acting. Do you plan to sell these new boards? It could be a solution to a problematic power stage that was difficult to work with and adjust to the circuits, it was not a reliable design. Thanks
Hi Hans, I want to ask you about your amp. Do you have any measurements of the noise floor of your amp?
What amp are you referring to ?
I don't have either a 23 or a 23.5 but a completely modified 20.6.
My initial plan was to transplant these modifications into the 23.X but issues with mechanical kept me from going on.
Hans
I don't have either a 23 or a 23.5 but a completely modified 20.6.
My initial plan was to transplant these modifications into the 23.X but issues with mechanical kept me from going on.
Hans
I'm refering 23.x because I measured my and found out that there is a noise which may come from the transformers because the ground and capacitors are very close the them.
Can you show a picture ?
That ground between the big caps is close to the transformer is exactly how it should be.
But maybe your regulated supply feeding the voltage amp is not performing well enough.
Hans
That ground between the big caps is close to the transformer is exactly how it should be.
But maybe your regulated supply feeding the voltage amp is not performing well enough.
Hans
That alu strip is a perfect gnd.
Can you show an AC scope plot taken on both large caps but also on the slightly smaller ones below the alu strip ?
Hans
Can you show an AC scope plot taken on both large caps but also on the slightly smaller ones below the alu strip ?
Hans
Look at this, the input has grounded on the board directly. This is the output through 2k/100 ohm divider
At the amp’s LS output sockets ?
If so, that’s totally wrong, it should be a flat noise floor with minimal signs of 50hz.
That’s why I ask you again to make scope pictures in AC mode on your 2 big and the 2 slightly smaller blue caps, to make sure they are o.k. all four. That would be my first thought as being the cause.
Hans
If so, that’s totally wrong, it should be a flat noise floor with minimal signs of 50hz.
That’s why I ask you again to make scope pictures in AC mode on your 2 big and the 2 slightly smaller blue caps, to make sure they are o.k. all four. That would be my first thought as being the cause.
Hans
Hello whitesnake,
I assume that you are making the measurements with the heatsinks+ PCB disconnected from the chassis?
We found out with Hans that there was a lot of oscillations if the chassis was not connected to the heatsinks. One extra cable is needed for that.
I assume that you are making the measurements with the heatsinks+ PCB disconnected from the chassis?
We found out with Hans that there was a lot of oscillations if the chassis was not connected to the heatsinks. One extra cable is needed for that.
