Hello Highstream,
The DirectStream DAC is described as having a transformer coupled output stage, and the ModWright 205 might also, as its description refers somewhat ambiguously to its analog stage as being transformer coupled.
Most XLR-to-RCA and RCA-to-XLR adapters short one of the two signal pins on the XLR connector (usually pin 3) to ground (XLR pin 1). Aside for some unusual exceptions (such as certain fully balanced Audio Research power amps, which require a balanced pair of signals at their inputs) that is appropriate in adapting to an XLR input, and is also appropriate in many cases when adapting to a transformer coupled XLR output. However, it can sometimes cause problems when adapting an actively driven XLR output (as opposed to one that is transformer coupled), since in those cases the active circuitry driving the signal that is shorted to ground may not be able to handle a zero ohm load.
So with respect to the connection between DAC and sub I would suggest that you contact both PS Audio and ModWright to verify that connecting the XLR output of each of those components to an RCA input via an XLR cable terminated with an XLR-to-RCA adapter which shorts pin 3 to ground is ok. I suspect the answer will be "yes" in these particular cases, but that should be confirmed with the manufacturers.
If it turns out to not be ok, though, Cardas can supply adapters on special order which leave pin 3 unconnected.
Also, I see that the input impedance of the E110 sub’s RCA inputs is 10K. I suspect both the DirectStream and the ModWright 205 will have no problem driving that impedance, but you might also ask the manufacturers to confirm that.
Regarding the connection from sub to speaker, I have been unable to find a spec on the output impedance of the sub or the input impedance of the speaker. I would suggest contacting both manufacturers to verify that impedance compatibility would not be an issue for that interconnection. But since in that case you would be adapting an RCA output to an XLR input, use of a standard adapter which grounds pin 3 shouldn’t be a problem in itself, as the experiment you’ve already performed appears to confirm.
Finally, just to be sure, I assume you are aware that the E110 provides speaker-level inputs, but that consistent with JL’s recommendation you anticipate interposing the sub and its high pass filter function between the DAC and the main speaker.
Good luck. Regards,
-- Al
The DirectStream DAC is described as having a transformer coupled output stage, and the ModWright 205 might also, as its description refers somewhat ambiguously to its analog stage as being transformer coupled.
Most XLR-to-RCA and RCA-to-XLR adapters short one of the two signal pins on the XLR connector (usually pin 3) to ground (XLR pin 1). Aside for some unusual exceptions (such as certain fully balanced Audio Research power amps, which require a balanced pair of signals at their inputs) that is appropriate in adapting to an XLR input, and is also appropriate in many cases when adapting to a transformer coupled XLR output. However, it can sometimes cause problems when adapting an actively driven XLR output (as opposed to one that is transformer coupled), since in those cases the active circuitry driving the signal that is shorted to ground may not be able to handle a zero ohm load.
So with respect to the connection between DAC and sub I would suggest that you contact both PS Audio and ModWright to verify that connecting the XLR output of each of those components to an RCA input via an XLR cable terminated with an XLR-to-RCA adapter which shorts pin 3 to ground is ok. I suspect the answer will be "yes" in these particular cases, but that should be confirmed with the manufacturers.
If it turns out to not be ok, though, Cardas can supply adapters on special order which leave pin 3 unconnected.
Also, I see that the input impedance of the E110 sub’s RCA inputs is 10K. I suspect both the DirectStream and the ModWright 205 will have no problem driving that impedance, but you might also ask the manufacturers to confirm that.
Regarding the connection from sub to speaker, I have been unable to find a spec on the output impedance of the sub or the input impedance of the speaker. I would suggest contacting both manufacturers to verify that impedance compatibility would not be an issue for that interconnection. But since in that case you would be adapting an RCA output to an XLR input, use of a standard adapter which grounds pin 3 shouldn’t be a problem in itself, as the experiment you’ve already performed appears to confirm.
Finally, just to be sure, I assume you are aware that the E110 provides speaker-level inputs, but that consistent with JL’s recommendation you anticipate interposing the sub and its high pass filter function between the DAC and the main speaker.
Good luck. Regards,
-- Al