Do not use 1uF of 4.7uF capacitor from signal hot to return since it creates a low pass filter with the source output impedance. The cut-off frequency of such filter can be anywhere in the range of 100th of Hz which explains your "blanket" over the speakers effect.
Now to your noise problem. Did you connect your amps PGND to chassis? Is your mains PE is connected to chassis as well?
To find the source of your noise you can start with a single channel connection. Just connect only one channel from the source and see if the noise is there. For this test do not use your preamp as it will complicate things, just use your CD player's volume control to attenuate the signal and feed it straight into the amp. Post here your observation regarding the noise level.
Regards,
Oleg
I am in the same situation but not problems at all
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Just for you guys to know that normally you should not use Class I equipment in your houses (except in the kitchen and bathroom) since it relies on PE connection for safety of operation. It is not guaranteed to be safe if PE connection is not present, otherwise it would have been Class II equipment for which PE connection is not needed for safety. Just sayin'...
This covers all you mention and more.... http://www.diyaudio.com/forums/diya...udio-component-grounding-interconnection.html
I have an older electrical system in my house too. Mostly ungrounded.
But I use a grounded extension cord when I test the new amplifiers.
Has also lived dangerous and tested without PE.
I can not hear any difference in noise. As soon as I connect the signal source,
The background noise comes.
I am using an old PC power supply metal chassis for testing my toroid transformer.
Mains are grounded (PE) in the chassis and transformer shielding is grounded in the same small chassis.
Amp is next to transformer on a wooden surface.Amp has a small heatsink.
Heatsink is grounded to HSND.
Amp is almost completely quiet when inputs are connected. I have to put my ear in to speaker to hear small noise. But when I turn on the signal source, noise comes
Back. It does not help to connect PGND from PCB to Chassis or any other
Configuration of ground hook up.
And, yes, I have a little reading to do.
But I use a grounded extension cord when I test the new amplifiers.
Has also lived dangerous and tested without PE.
I can not hear any difference in noise. As soon as I connect the signal source,
The background noise comes.
I am using an old PC power supply metal chassis for testing my toroid transformer.
Mains are grounded (PE) in the chassis and transformer shielding is grounded in the same small chassis.
Amp is next to transformer on a wooden surface.Amp has a small heatsink.
Heatsink is grounded to HSND.
Amp is almost completely quiet when inputs are connected. I have to put my ear in to speaker to hear small noise. But when I turn on the signal source, noise comes
Back. It does not help to connect PGND from PCB to Chassis or any other
Configuration of ground hook up.
And, yes, I have a little reading to do.
The type of outlets without ground are not permitted anymore in new buildings.
I'm sure in the Netherlands the old code was to keep electrical wiring cheaper. Costs over safety.
O I thought ClaveFremen was.
However he signs off with Dario...so I assumed Dario was his first name. Perhaps I better refer to his diyAudio name in future?
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Probably a good assumption.
But his unique Forum name is there for everyone to use and search for.
There are dozens of Andrew here, but each Member has his/her own unique name.
BasH is possibly enough to be unique to you. I would tend to use that if I needed to refer back to some post/quote.
But his unique Forum name is there for everyone to use and search for.
There are dozens of Andrew here, but each Member has his/her own unique name.
BasH is possibly enough to be unique to you. I would tend to use that if I needed to refer back to some post/quote.
A HFI relay is a demand from the authorities in Danish houses . On the other hand , no demand for earth connections in outlets (except bathrooms).
This should prevent dangerous electrical shock if earth and return is not at the same potential.
Wow... a lot of confusion...
I never said not to use PE, the chassis MUST be connected to PE.
It's obvious that the house should have PE in each outlet, at least here in Italy it's mandatory, or EVERY object branched to electricity without double insulation would be potentially dangerous.
The My_Ref it's no different.
What should not be connected (for best performance) to PE are the My_Ref Fremen Edition modules, exactly like My_Ref Rev C. and My_Evo (Evolution Rev. A) since this is a floating amp.
This is a DIY project, not a finished commercial one, we should also not forget it.
Dealing with electricity is always potentially lethal and the utmost care should be taken.
If the amp is encased in a metal case connected to PE, with fuse and insulated output connectors, properly built and connected to an outlet with PE it's perfectly safe, just like the big part of the projects presented here on DIYAudio.
I never said not to use PE, the chassis MUST be connected to PE.
It's obvious that the house should have PE in each outlet, at least here in Italy it's mandatory, or EVERY object branched to electricity without double insulation would be potentially dangerous.
The My_Ref it's no different.
What should not be connected (for best performance) to PE are the My_Ref Fremen Edition modules, exactly like My_Ref Rev C. and My_Evo (Evolution Rev. A) since this is a floating amp.
This is a DIY project, not a finished commercial one, we should also not forget it.
Dealing with electricity is always potentially lethal and the utmost care should be taken.
If the amp is encased in a metal case connected to PE, with fuse and insulated output connectors, properly built and connected to an outlet with PE it's perfectly safe, just like the big part of the projects presented here on DIYAudio.
This is unnecessary controversy...
You know this project and me pretty well and you already know that I never recommended that madness... can't you simply be constructive and stop this nonsense?
Dario, the problem is a bit more complicated. In the case of fault RCA connectors and the binding posts tied to amps GND can become live while the amp would still operate fine and speakers would produce sound. For this to happen the live mains wire inside the chassis has to touch the GND of a floating amp. Such fault will sit there for a long time waiting for someone to reconnect the inputs or speaker wires on the working amp and get killed.