I can't break the ground can I ? It would leave the live just floating about, without anything to measure a potential difference against. The amp would work, but it's volume control could be unstable.
The actual setup is an 8000a as pre-amp and one of the main amps. Used like a two box. With a second amp in play, perhaps for the bass section.
This 8000a came in for new sockets. and I found the board too chassis connection had failed (they soldered to the chassis). This was exhibiting the odd volume control, where low level volume couldn't be controlled, and it ramped up very quickly to full. Until the grounds were fixed. I have seen it with other failed leads to. I'm sure it's a thing.
The 10 ohms strikes me as good, as why take a difficult path. Though I also see it creates a greater voltage drop over the lead, if there is one to present itself. I too will need a read. It's gone 12, all I need right now is another cold one
Feel free to pad this thread with as much related info as you feel fit. It's all good stuff. Now and for future readers.
The actual setup is an 8000a as pre-amp and one of the main amps. Used like a two box. With a second amp in play, perhaps for the bass section.
This 8000a came in for new sockets. and I found the board too chassis connection had failed (they soldered to the chassis). This was exhibiting the odd volume control, where low level volume couldn't be controlled, and it ramped up very quickly to full. Until the grounds were fixed. I have seen it with other failed leads to. I'm sure it's a thing.
The 10 ohms strikes me as good, as why take a difficult path. Though I also see it creates a greater voltage drop over the lead, if there is one to present itself. I too will need a read. It's gone 12, all I need right now is another cold one
Feel free to pad this thread with as much related info as you feel fit. It's all good stuff. Now and for future readers.
@ friendly1uk
Only disconnect the cable shield at the destination end if you experience hum.
Provided your source and destination equipment are both Class 1 then the live (hot) signal will remain voltage referenced to the system ground.
Pin 2 connected with pin 3 left floating works perfectly well between my son's balanced mixer/interface and unbalanced amplifier with absolutely no volume control issues.
If you want to be absolutely sure then go down the more expensive path of galvanic isolation via a transformer.
Only disconnect the cable shield at the destination end if you experience hum.
Provided your source and destination equipment are both Class 1 then the live (hot) signal will remain voltage referenced to the system ground.
Pin 2 connected with pin 3 left floating works perfectly well between my son's balanced mixer/interface and unbalanced amplifier with absolutely no volume control issues.
If you want to be absolutely sure then go down the more expensive path of galvanic isolation via a transformer.
My mistake just pulled me back to post. School boy error. It's only in the presence of a loop, that you would cut the ground. But the ground would still be connected. Just through another path. Or there would never of been a loop.
I didn't have an alternate path when I lacked the ground wire. That's why it failed to work correctly.
So basic. So very basic. Doh.
I didn't have an alternate path when I lacked the ground wire. That's why it failed to work correctly.
So basic. So very basic. Doh.
Such 'doctoring' of the power lead may be OK in a permanent installation, but for the safety of the average user I repeat:
NEVER remove the safety earth (ground) from an item of equipment.
In a non-permanent installation there is a danger that such a 'doctored' item of equipment could be removed and used independently of the system on which it depended for its safety grounding.
With the safety earth disconnected in the power lead the 'doctored' item would represent a safety hazard if used elsewhere.
I agree in principle, but breaking the cable screen may work perfectly well in regard to a 'hummy' balanced to unbalanced, transformerless interconnect. It's worth giving this a try before going to more trouble and expense.
Ground is a reference point from which the signal is measured, so the justification for your thought may be that a clean signal ground is essential.
The OP may be fortunate enough to discover that he has a ground which injects no noise. In which case, job done!
If not, he will have to dig deeper into his pocket and do the balanced to unbalanced conversion in the accepted manner, using isolating transformers.
No, the circuit floats above the reference. My concern is that the flow and return is not close coupled.
I understand it is preferable that the signal return be a dedicated line rather than the ground, which is potentially noisy. However, I need help to understand the above statements.
By 'close coupled' do you mean that the signal flow and return should be in close physical proximity? If so, is that for reasons other than to minimise hum and noise pick-up?
By 'the circuit floats above the reference' do you mean that the signal return may be at a different potential than the ground? If not, please expand a little.
P.S. I did a search for 'close coupled' but I only came up with toilets!
Thanks dtaylo3.
The video explores how to connect XLR to RCA. However, most of the video time is spent explaining the difference between balanced and unbalanced.
Only near the end of the 8m 38s are we told simply to connect the hot and leave the cold floating.
Exactly what I've suggested in this thread!
P.S. Only for impedance balanced and active balanced outputs!
The video explores how to connect XLR to RCA. However, most of the video time is spent explaining the difference between balanced and unbalanced.
Only near the end of the 8m 38s are we told simply to connect the hot and leave the cold floating.
Exactly what I've suggested in this thread!
P.S. Only for impedance balanced and active balanced outputs!
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Yes, it's a physical thing to reduce the loop area and noise pick up
Signal return completes the circuit, it isn't necessarily related to ground
This is a very good article http://hifisonix.com/wordpress/wp-c...to-wire-up-a-Power-Amplifier-October-2017.pdf
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