XLR or RCA cables

I am currently running 2 meter RCA interconnects with adapters at the amp but was wondering if running XLR cables with an adapter at the preamp would offer any improvement.

In principle, using an XLR cable with an adapter at the preamp is the better of the two approaches, in part because it would provide somewhat better rejection of hum and noise. It corresponds electrically to the configuration shown in Figure 2.1 of this Jensen paper.

In principle, using a Jensen transformer would be a much better approach, as suggested above and as described in the paper.

As a practical matter, and assuming that you do not presently have perceivable problems with hum or noise, whether or not either of those alternatives would provide an improvement in your particular setup is anyone's guess IMO.

Regards,
-- Al

The Jensen transformer sounds intriguing. Where can I get information on them or purchase one?

Jensen Home Page (click on "Iso-Max Audio Isolators" in the upper left, and then scroll down)

PI-2RX Datasheet (same as PI-2XX shown, except with RCA input connectors)

PI-2RX Manual

It would be best to give them a call before ordering, though, to confirm that this specific model is what they would recommend for your particular system.

Also, if your amp(s) are monoblocks, to keep the cable length between transformer and amp short (as required for an "input transformer" such as this) you should get two of the single-channel version, which would be model PI-1RX.

Regards,
-- Al