KenL,
I'm not sure whether or not the Pass XA series amps would be good matches for a passive volume control, because of the XA's relatively low input impedance (20K unbalanced, 30K balanced). Although I note that Stereophile's measurements indicate that those impedances are "constant across the audio band," which will help matters. You should probably raise that question in a separate thread if you decide to pursue that possibility.
As you may be aware, the XA30.5 is considerably more powerful than its rating suggests, and JA's measurement in the Stereophile review was 195 watts into 4 ohms (although the amp leaves Class A operation at considerably less than that).
The Maggie 1.7's sensitivity of 86db/1m/2.83V corresponds to 83db at 1 meter for 1 watt input into its 4 ohm nominal impedance. 195W will result in about 106db at 1 meter. Given that for planar speakers volume levels fall off relatively slowly with distance, that strikes me as reasonable in relation to your small room dimensions and music preferences, assuming that the spec is accurate.
As far as interfacing the balanced output of the Rowland to the unbalanced input of the RVC is concerned, my suggestion would be to have a custom cable made up which connects xlr pin 2 to the rca center pin (assuming the Rowland conforms to the USA convention of pin 2 non-inverted and pin 3 inverted); xlr pin 1 to the rca ground sleeve; and leaves xlr pin 3 open. If you were to use a standard adapter, that would most likely ground pin 3, which would mean that the Rowland's output signal on that pin would be shorted to ground. Most equipment can tolerate that, but some cannot. Check with Rowland on that point if you would prefer to use an adapter.
If you want to consider a transformer instead of an adapter cable, my instinct with gear of that caliber would be to go with a Jensen. Although for the price at which B&H is currently offering the ART DTI, there is essentially no downside to experimenting with it.
Regards,
-- Al
I'm not sure whether or not the Pass XA series amps would be good matches for a passive volume control, because of the XA's relatively low input impedance (20K unbalanced, 30K balanced). Although I note that Stereophile's measurements indicate that those impedances are "constant across the audio band," which will help matters. You should probably raise that question in a separate thread if you decide to pursue that possibility.
As you may be aware, the XA30.5 is considerably more powerful than its rating suggests, and JA's measurement in the Stereophile review was 195 watts into 4 ohms (although the amp leaves Class A operation at considerably less than that).
The Maggie 1.7's sensitivity of 86db/1m/2.83V corresponds to 83db at 1 meter for 1 watt input into its 4 ohm nominal impedance. 195W will result in about 106db at 1 meter. Given that for planar speakers volume levels fall off relatively slowly with distance, that strikes me as reasonable in relation to your small room dimensions and music preferences, assuming that the spec is accurate.
As far as interfacing the balanced output of the Rowland to the unbalanced input of the RVC is concerned, my suggestion would be to have a custom cable made up which connects xlr pin 2 to the rca center pin (assuming the Rowland conforms to the USA convention of pin 2 non-inverted and pin 3 inverted); xlr pin 1 to the rca ground sleeve; and leaves xlr pin 3 open. If you were to use a standard adapter, that would most likely ground pin 3, which would mean that the Rowland's output signal on that pin would be shorted to ground. Most equipment can tolerate that, but some cannot. Check with Rowland on that point if you would prefer to use an adapter.
If you want to consider a transformer instead of an adapter cable, my instinct with gear of that caliber would be to go with a Jensen. Although for the price at which B&H is currently offering the ART DTI, there is essentially no downside to experimenting with it.
Regards,
-- Al