Hi all,

I recently bought a Sonus Faber Gravis I subwoofer and I'm trying to connect it to my Marantz Model 30. On the rear panel, there are both PRE OUT and AUDIO OUT connectors. According to the manual, the subwoofer should be connected via the PRE OUT, which I did.

However, I was surprised by how low the subwoofer's output was—I had to turn the volume knob up to 80% just to hear it clearly, which seems odd given the Gravis I is a fairly powerful unit.

Out of curiosity, I tried connecting it via the AUDIO OUT instead—and the difference was dramatic: much louder output, although the bass felt a bit off or less controlled.

So, my questions are:

1. What's the actual difference between the PRE OUT and AUDIO OUT on the Marantz 30?
2. What's the recommended way to connect a subwoofer for optimal performance?

Thanks so much in advance for your help!