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balanced output VPI

I just bought a RCM Prelude Sensor phono pre. This phono pre has the option for balanced input over RCA. I own a VPI scout wich means I can use a normal RCA cable. Can I just flip the dip switch on teh back of my RCM to have the benfit of balanced input or are things more complicated then that?

The interlink I use is a special RCA RCA phono cable with an extra clamps for ground signal.
mordante
dtc's avatar
dtc
1,047 posts
 
I checked my Scout junction box. The sleeve of the RCA output is not tied to the ground nut. So, I believe the negative sides of R & L of the cartridge are connected to the corresponding sleeves of the RCAs, as I suspected. It seeems that the configuration is, although I did not check the continuity from the headshell to the RCAs.

L + Center Pin L RCA
L - Sleeve L RCA
R + Center Pin R RCA
R - Sleeve R RCA
Chassis to grounding nut on junction box.

This is the situation that AtmaSphere described above and is described in his manual.

The RCM manual clearly shows that the switch on it simply connects the sleeve of the RCA either to ground or to the minus input of the phonostage.

So, a standard RCA should work for balanced mode, with the caveat that the shield on the RCA cable is the negative balanced signal, not a ground.

The best solution would be a 2 conductor cable with a ground shield. Again, it is not clear what configuration your cable is, but it may be the appropriate cable.

Again, I am not an expert, but that is what I have found out. Since it corresponds to what AtmaSphere said, it might be right. He actually knows what he is talking about.

Hope it helps.
brf
1,715 posts
 
Dtc, in the RCM Prelude owner's manual, there are detailed pictures and instruction on how to wire a rca phono cable to take advantage of the Prelude's balanced circuit.
dtc's avatar
dtc
1,047 posts
 
Brf - I understand the RCM schematics. However, you also need to understand the VPI configurations to be sure everything works in balanced mode.

I am simply trying to provide a view of the connections on the VPI side. Fortunately, I think the VPI provides both the appropriate positive and negative signals to the RCA connections that will allow the RCM to function with balanced inputs, with the proper cabling

To be overly blunt, just looking at the RCM configuration is not sufficient to be sure the whole system will work correctly. You need to look at the VPI side also, which I think I have done.

Fortunately, I think the VPI and RCM configurations will work to provide the appropriate balanced connections needed, with the proper cabling.
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