Malka,
the quote from my post and your diagram/enquiry are not related. I can't see why you posted the quote.
Sorry Andrew, maybe i was'nt clear in my question...What i was trying to ask was, is this the correct place for Main Audio Star Grounding? RegiRegi22 Told me to connect the CL60 inbetween the two main filter caps...however you replied saying "The Main Audio Star Ground can be after a short link from the main smoothing cap Zero Volts. Even 1mm of short link would do the job properly." So i quoted that and attached the pic, to ask if this was the correct place to link the CL60 to?
Thanks
Alon
Thanks
Alon
As I thought, completely unrelated.
The CL60 is a Safety issue. It is done to protect users and visitors from harm. It is NOT used to allow Audio to pass.
The separation of PSU ripples and grunge from Amplifier main Audio Ground is all about trying the get the best Audio signal through. Absolutely nothing to do with Safety.
The Chassis is connected permanently to the PE (third wire in the mains cable). This is what I have been calling the Safety Earth to avoid ambiguity.
All exposed conductive parts must be connected (eventually) to the Safety Earth. You could do that at the speaker return terminal, or at the CT of the mains transformer, or at the RCA nut clamping the input socket. But this must be able to pass fault current approaching and in worst case exceeding kA to PE and continue to do so until after the fuse has ruptured and the arc extinguished.
This is an onerous condition. I have tested a bridge rectifier direct on line to pass this Fault current. I have not tested a CL60 to this standard.
The CL60 is a Safety issue. It is done to protect users and visitors from harm. It is NOT used to allow Audio to pass.
The separation of PSU ripples and grunge from Amplifier main Audio Ground is all about trying the get the best Audio signal through. Absolutely nothing to do with Safety.
The Chassis is connected permanently to the PE (third wire in the mains cable). This is what I have been calling the Safety Earth to avoid ambiguity.
All exposed conductive parts must be connected (eventually) to the Safety Earth. You could do that at the speaker return terminal, or at the CT of the mains transformer, or at the RCA nut clamping the input socket. But this must be able to pass fault current approaching and in worst case exceeding kA to PE and continue to do so until after the fuse has ruptured and the arc extinguished.
This is an onerous condition. I have tested a bridge rectifier direct on line to pass this Fault current. I have not tested a CL60 to this standard.
Ok Thanks Andrew for the explanation, however i am still a little lost😕
Could sombody please draw me a diagram, so that i can see where the main ground is? I find pictures much easier to follow then txt.
Thanks
Alon
Could sombody please draw me a diagram, so that i can see where the main ground is? I find pictures much easier to follow then txt.
Thanks
Alon
Hi,
the centre terminal of the 3way is labeled 2.
This is the CT connection from the transformer.
You can connect chassis to terminal2 since it uses heavier wire than elsewhere, or you can connect chassis to the transformer CT before you take it to the PCB.
the centre terminal of the 3way is labeled 2.
This is the CT connection from the transformer.
You can connect chassis to terminal2 since it uses heavier wire than elsewhere, or you can connect chassis to the transformer CT before you take it to the PCB.
I connected the CT to the chassis via a 22ohm resistor(its all i had to hand) bypassed by a 0.01uf cap...the hum and buzz is still there, but the soundstage seems wider and deeper, cleaner sounding, bass has more omph.
Is there anything else i can try, in order to eliminate the hum/buzz???
Alon
Is there anything else i can try, in order to eliminate the hum/buzz???
Alon
Thanks Salas, i hav'nt tried that yet...will give it a try tomorrow. I will unbolt the transformer from the chassis, and try moving it further away as well.
The small one too. Try rotation and angles/distance. If their field is a factor it will be obvious by changing the background buzz.
P.S. You are running a long 240VAC primary twisted pair diagonally across the chassis I saw. You can mount the little Tx to the right and perpendicular at least.
P.S. You are running a long 240VAC primary twisted pair diagonally across the chassis I saw. You can mount the little Tx to the right and perpendicular at least.
Hi Richard, I did'nt get a chance to play around with it today...too busy and feeling lazy...but i did listen to some music, and the hum and buzz is very quiet...can only be heard with my ear right up near the speakers...still would be nice to have it dead silent.
How are you getting on with your hum problem?
Alon
How are you getting on with your hum problem?
Alon
Your hum sounds very much like my...hum. Sooner or later everyone will want one, just you wait!
I'm about to try Fran's copper bar to see if that helps.
Whats the copper bar?? sounds interesting...let me know how it goes, i'll keep you posted as well...maybe together we can solve this hum problem!!!
Alon
Alon
Hi Alon
I added a copper grounding bar to my RCA ground tabs, along with an ESP ground loop breaker. The hum remains 🙁
I added a copper grounding bar to my RCA ground tabs, along with an ESP ground loop breaker. The hum remains 🙁
We need a "HUM" Thread.
I have "HUM" in every amp I built and disconnecting the chassis ground removes the hum.
I built Uriah's LDR Volume control and it has a HUM I can't eliminate. No HUM when unplugged but when I plug it in the HUM starts.
Going to try battery power next.
I have "HUM" in every amp I built and disconnecting the chassis ground removes the hum.
I built Uriah's LDR Volume control and it has a HUM I can't eliminate. No HUM when unplugged but when I plug it in the HUM starts.
Going to try battery power next.