Length of ground buss in s.e.x. 2.1?

[jrebman]

I don't seem to be able to figure this out, at least not to my satisfaction, from the manual, so could somebody who has built the 2.1 tell me how much ground buss wire there is in total -- not just the uninsulated buss wire, but the busses for the main amplifier sections as well?

At long last my top plates for the s.e.x. and eros are back from the powdercoater and in a couple of days I'll be ready to start building and I want to start with the s.e.x. and I want to gather all the bits and pieces together ahead of time -- upgraded pieces, that is.

Thanks,

Jim

 

[Noskipallwd]

Jim, in my manual you have the safety ground lug that has, 4 wires going to it. About 10" of black insulated wire is called for, not the(uninsulated) bus wire, IIRC the rest of the grounds go through or from various components to the terminals, somebody correct me if I am wrong. The signal ground is tied into PT terminal 10 and uses 5 pieces of the black insulted wire from terminal strip to terminal strip, about 21-22" in all. If you don't mind me asking, are you planning on replacing the wire? It will take some time to come up with a total figure. Due to the size of all the caps I installed it's difficult to follow any of the wiring. Hope this helps some.

Cheers,
Shawn

 

[jrebman]

Shawn,

Thanks, and yes, at least I'm considering replacing the ground wire with silver, but not sure yet if I'll actually do it.

Thanks for the help though, it does help some, at least I'll know where to look in the manual.

-- Jim

 

[Paul Joppa]

For what it's worth, there are two different grounds in most of our products.

The safety ground usually goes to a lug near the IEC socket, which connects to the chassis. Transformer and choke cores go here, and sometimes a heater winding. The purpose is to drain hum that is capacitively coupled from the power line, to the safety ground. None of these are directly in the signal path or signal current loop.

Separately, there is a signal ground bus, usually attached to the chassis near the input circuitry. As much as possible, the routing is chosen so that any ground currents create the smallest possible signal at the sensitive input circuitry. The chassis connection point approximates a single-point ground - it usually has many wires coming to it or to very nearby ground lugs. These are the ground points and wires that have a significant possible effect on the sound.

The two are connected to each other through the chassis, since both attach to it a one point each. By separating them, and by chassis-grounding the signal ground near the input, any hum or noise currents in the chassis plate (i.e. between these grounds) should have minimal effect on the signal circuitry. At least that's the theory part!

 

[jrebman]

Paul,

Thanks for the explanation -- and yes, I should have specified the signal ground.

I've always been impressed with the grounding of the BH products, BTW.

-- Jim