Cliff style jack on new amp build

[JPK]

Please see attached. I'm building a new one watt amp and being told by the people that make the kit that the input jack self grounds to the chassis. From what I see it's totally isolated. In other words I need to run a wire from the input jack's negative terminal to a chassis ground. From what I remember this should be right next to the input jack. It's been about 10 years since I built my AX84 October so I'm a little rusty on all this. Trying to get back up to speed. This doesn't look right without my adding a ground wire and chassis ground.

[JPK]

I just went to open up my AX84 High Octane which has the same input jack. I have a ground going back to the main chassis ground. On the HO I used the Aiken star ground, one single point for all grounds except mains, which has its own chassis ground. So it appears this one will need it too. Unless someone knows how this thing self grounds to the chassis.


Pic below. Don't laugh, my first build. It's actually an AX84 High Octane Chris Hurley layout that is dead quiet. I built it about 15 years ago. I won't ever do a terminal strip build again.

[g-man]

Deleted

[JPK]

Sure looks like the standard isolated jack. You could install it on the chassis and check resistance between the chassis and jack lugs to confirm.

It is most definitely an isolated jack. I installed it as you suggested and did a continuity test. It did not ring. I'll have to figure out how I want to ground it.


Got a little soldering done today. Fun stuff.

[PRR]

> figure out how I want to ground it.

[pdf64]

Please see attached. I'm building a new one watt amp and being told by the people that make the kit that the input jack self grounds to the chassis. From what I see it's totally isolated. In other words I need to run a wire from the input jack's negative terminal to a chassis ground. … This doesn't look right without my adding a ground wire and chassis ground.

As I see it, that layout should work as drawn.
The input socket sleeve terminal connects to the necessary stuff, there’s no necessity to add any other wires.

[JPK]

> figure out how I want to ground it.

That would work. Thanks.

[JPK]

Please see attached. I'm building a new one watt amp and being told by the people that make the kit that the input jack self grounds to the chassis. From what I see it's totally isolated. In other words I need to run a wire from the input jack's negative terminal to a chassis ground. … This doesn't look right without my adding a ground wire and chassis ground.

As I see it, that layout should work as drawn.
The input socket sleeve terminal connects to the necessary stuff, there’s no necessity to add any other wires.

The only issue I see is that all those common points are not actually connected/bonded to any chassis ground. It's floating. I'm sure many have built the amp per the layout (with no extra chassis ground wire) and had no problems, but it doesn't follow the last two amps I built. I've read your and many other experienced members' posts, you guys know a lot more than I do, so I respect your view.

[thetragichero]

ground buss doesn't have to come in contact with the chassis at all for an amp to work safely, but it may be beneficial

[pdf64]

… all those common points are not actually connected/bonded to any chassis ground. It's floating. …

The drawing shows the input socket sleeve terminal connected to a bus wire soldered to the back of the pots, and hence it will be connected to the chassis via the pots.
The chassis is used as a 0V common conductor between the various circuit common connections to it.

[JPK]

… all those common points are not actually connected/bonded to any chassis ground. It's floating. …

The drawing shows the input socket sleeve terminal connected to a bus wire soldered to the back of the pots, and hence it will be connected to the chassis via the pots.
The chassis is used as a 0V common conductor between the various circuit common connections to it.

Well there you have it, thanks. Too bad the guy I asked (where I bought the kit) didn't point that out. He just said the input jack was "automatically" grounded to the chassis, which it wasn't. It was grounded via the the pots which are. Very cool that you saw that. Saved me a wire.   


Note that the output jacks are the same type and they ran a ground wire to the chassis ground. So this amp appears to be solidly designed. I just wonder if it's any quieter to have one (or two) chassis ground like Aiken's white paper on grounding suggests (linked below). This one has multiple chassis grounds which, from memory, might cause ground loops.


https://www.aikenamps.com/index.php/grounding
.