I recommend you look at where the Signal Current flows from the (external interconnect and back to the interconnect. It's the Return route and it's closeness to the Hot route that determines LOOP AREA.
Using coax connected at ONE end and taking the Return Current via a separated Return wire achieves nothing, I mean nothing !!!
Using coax connected at ONE end and taking the Return Current via a separated Return wire achieves nothing, I mean nothing !!!
Yes, that is how I wired the jacks. The PCB input connectors have 3 pins, L & R hot and a single ground. I chose to join the grounds of the jacks and the shields of the cables at that side, and run a single wire to the ground pin of the input connector. I make no claim that this is a good way to do it, but I have not had any problems (that I am aware of).
Andrew: I'm sure you are right. At the very least tying the 3 wires into a bundle would probably help. I assume I am saved by the fact that the whole mess is enclosed in a grounded aluminum chassis. I simply wanted to use shielded coax so that the signal conductor would be wrapped in an electrostatic shield, while solving a mechanical problem by using a single wire to tie the 3 ground points together (L & R RCA's plus the ground connector on the circuit board).
How would you assess turntable wiring schemes that use a separate ground wire?
PS: Please excuse my wiring, the photo was just to show the coax cable.
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the SIGNAL is a two wire connection.
The amplifier measures the difference between the TWO ends of that signal connection and does it's best to reproduce a copy of that difference signal.
If you have a loop area in the signal connection then even when it is inside your enclosure it can pick up interference from all the other emitters inside that enclosure and if the chassis has big gaps (I mean long slots or gaps) the the external RF can also affect the signal loop.
You really must aim for LOW LOOP AREA in every wire pair.
A R+L + single Return can be bound together with the R & L on opposite sides of the Return. The intervening Return will help to reduce crosstalk. That slight crosstalk intrusion is far better than a big loop area and all the interference that the loop will pick up.
This close coupling of R+L will probably apply to the external interconnects. They usually come from a common ground source and a gap between the interconnects will pick up interference when they are recoupled inside the enclose. That's a big probelm that is forgotten about in multi-channel amplifier and overcome in monoblocks. Dual monodoes not solve this as far as I can see. The old and ridiculed interconnects that came as a figure of 8 pair kept the loop area low !!!!!!
The amplifier measures the difference between the TWO ends of that signal connection and does it's best to reproduce a copy of that difference signal.
If you have a loop area in the signal connection then even when it is inside your enclosure it can pick up interference from all the other emitters inside that enclosure and if the chassis has big gaps (I mean long slots or gaps) the the external RF can also affect the signal loop.
You really must aim for LOW LOOP AREA in every wire pair.
A R+L + single Return can be bound together with the R & L on opposite sides of the Return. The intervening Return will help to reduce crosstalk. That slight crosstalk intrusion is far better than a big loop area and all the interference that the loop will pick up.
This close coupling of R+L will probably apply to the external interconnects. They usually come from a common ground source and a gap between the interconnects will pick up interference when they are recoupled inside the enclose. That's a big probelm that is forgotten about in multi-channel amplifier and overcome in monoblocks. Dual monodoes not solve this as far as I can see. The old and ridiculed interconnects that came as a figure of 8 pair kept the loop area low !!!!!!
stepped ladder volume control
Hi, I've found this ... on ebay (from Jim's Audio)
Resistor Volume Control 128 Steps Stereo P1 7 Balanced w Highly Reliable Relay | eBay
how suitable would it be as a front end to the dcb1 buffer?
I'd prefer not to use the pot. I'm looking into remote possibilities.
Hi, I've found this ... on ebay (from Jim's Audio)
Resistor Volume Control 128 Steps Stereo P1 7 Balanced w Highly Reliable Relay | eBay
how suitable would it be as a front end to the dcb1 buffer?
I'd prefer not to use the pot. I'm looking into remote possibilities.
No direct experience. If it works OK as a 20K pot then its as good as any pot in front of a DCB1.
"Input Impedance : Between 1M to 10K, the frequently used volume levels between 20K to 50K
Output Impedance : 4K to 1M, the frequently used volume levels between 4K to 30K"
Should be ok, right?