Unbalanced to balanced input gain

[SmokinJoe]

Looking for some advice I have a Crown CDi 1000 that I have configured in bridged mode and crossed for sub duty. My problem is the Sub output from the Dennon AV amp is RCA (single ended) and the Crown amp only has Balanced input. I used an adaptor to bridge between the two which works but output is limited due to the output being half the full gain of the balanced input the Amp requires for full output. I'm sure the impedance difference doesn't help this either.
My question is there a device for matching the impedance AND boosting the signal to allow full input signal to the Crown CDi amp?
I tried the Clean Box Pro. it is not a preamp. it actually loses a bit in the conversion. Sent it back! needs to actually boost the signal to full gain on a balanced input.

 

[JStewart]

You mean like this?

CLEANBox Pro – Dual Channel Level Converter – ART Pro Audio

artproaudio.com

 

[DanDan]

I am pretty sure you can fix this just by some wiring and tweaking gain pots. I would try RCA Hot to XLR Phase + and RCA Screen to XLR Phase - That will cause maximum hum cancellation at least. You might then get some more gain by grounding XLR Phase 1.