ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Hello
I'm building a passive volume control to connect my turntable and RIAA preamp (Pro-ject phono box mm) to a set of Beloab 8000 active speakers.
I was wondering if the right/left signal pins on each of the two 8-pin DIN sockets I'm using for the powerlink should be shorted or if there should be some resistance between them. I have a Beolab 5000 amp laying around so I checked the resistance between pins on the two powerlink sockets on that one. Turns out there is a ~3Ohm resitance between each pin, except for the #2 pins which are ground.
So do I need to add 3ohm resistors between the two sockets, and if so, why?
That's the amp section from a Beolab 5000 speaker, right? The Powerlink connectors are simply connected in parallel. The 3 ohms must be due to bad connections.
--mika
Yes, that's the one.
I thought they should be shorted as well, so I was surprised to see the resistance measurement.
It was quite consisten for all pins except the ground pin, so I'm hesistant to write it off as "bad" connection.
Could be that the ground is connected via a bus bar or the chassis, while the signal pins are connected via thinner wire?
Also, I measured this through a couple of powerlink cables (my probes wouldn't fit the sockets). If the ground pin is connected to the cable shield I guess it could explain the apparant lower resitance, but are the powerlink cables even shielded?
Marius
The extra cabling etc may well add a few ohms. Anyway, it's not designed into the circuit - no need to replicate resistances that are not supposed to be there