Signal ground connection question

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Solecky

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I am thinking of playing around with signal ground on my system next to see what happens. I have a Luxman c900 preamp and m900 monos and an esoteric k01xd. All have a signal grounding terminal in the bAck. The owners manual says the following below from both Luxman and esoteric. I was thinking of connecting all the units together with the preamp as the central unit. Is it a simple as connecting a grounding wire from each unit to the preamp or not? Please advise, thx!

From Luxman
Is a ground terminal for devices to be connected to this unit. This terminal is used to reduce noise when other devices are connected to it.
 
Solecky said:
Is it a simple as connecting a grounding wire from each unit to the preamp or not?
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No.

Before you connect anything to the ground post of your Luxman, find out from Luxman whether this is a connection for connecting to chassis ground or signal ground. They are completely different things.
 
Puma Cat said:
No.

Before you connect anything to the ground post of your Luxman, find out from Luxman whether this is a connection for connecting to chassis ground or signal ground. They are completely different things.
Click to expand...

How many preamps and power amps have a ground post that isn’t a chassis ground?
 
mep said:
How many preamps and power amps have a ground post that isn’t a chassis ground?
Click to expand...

All my components have a signal ground terminal see the pictures
 

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Solecky said:
The terminal on all my Luxman gear and esoteric is labeled signal ground not chassis ground. Still no?
Click to expand...

Ah, okay.

Per your photos, you can connect a wire from the ground shell of an unused input jack on your other components to the Signal ground connector on your Luxman. A simple way to do this is to buy some CCTV RCA plugs that have a screw terminal for + and - . Connect a wire to the - terminal only to connect the ground shell of that plug, plug it into an unused RCA jack on your other components, and you can connect the other end of that wire to your Luxman's signal ground post. It looks like the component in the middle photo is a DAC (?)...you could also connect a wire from that ground post to the signal ground of your preamp.

I would try this one component at a time and listen for improvements.
 
So your going to make parallel ground paths? And what if some grounds are copper and some silver and they vary in length. Who knows, it may work. But all your interconnects have a signal ground tying the components togethet.

If it is a signal ground, my guess is it would be better used to a ground box looking to drain noise.

Let us know if it works or if you end up with ground loops.
 
Solecky said:
All my components have a signal ground terminal see the pictures
Click to expand...

It might say “signal” ground, but the schematic symbol underneath the ground post in your pictures is a chassis ground symbol.
 
mep said:
It might say “signal” ground, but the schematic symbol underneath the ground post in your pictures is a chassis ground symbol.
Click to expand...

It's easy enough to find out. Just measure the resistance between the post and the chassis.
 
Solecky said:
BlueFox
Thx i am a rookie, what should it read if it is chassis vs signal ground?
Click to expand...

Basically, if it is chassis ground then it should read zero ohms between the post and the chassis. If it is signal ground it should read "infinity" between the post and the chassis. Infinity will be a very high (Meg ohms) resistance reading.
 
BlueFox said:
Basically, if it is chassis ground then it should read zero ohms between the post and the chassis. If it is signal ground it should read "infinity" between the post and the chassis. Infinity will be a very high (Meg ohms) resistance reading.
Click to expand...
Wouldn't this depend on how the signal ground is grounded, or not. If the signal ground is tied to the circuit power ground, which is tied to the chassis, then it would be 0 ohms unless a resistor is in the path. Then you would read the resistor value.

If it's floating it would be an open circuit.

I would not mess with trying to bond case grounds. It seldom seems to do anything. And the mess of wires can pick up noise from power wires or act as an antenna and pick up RF, then inject it into your ground. But more your making multiple ground paths. Your power cords should be your single point ground reference.

My phone does not show pictures. Now that I am on a computer, I see them and it does look like it could be a ground tied to the signal. If that is the case, that is a place I would land a ground to an Entrique type box. I would not try bonding them together. That would be a path right into the amplification gain stage and noise could really get amplified.

Of course, the itch is hard to ignore till you scratch it.
 
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