I was thinking I could hook these up directly to speakers or headphones via RCA cables and a Y-splitter.

Speakers and headphones require amplification. It takes electricity to drive the magnets to move the cones.

Line-level output from any piece of audio gear (whether it's an Empeg or a synthesizer or a tape player or whatever) doesn't have enough power to drive the magnets in a set of speakers. It's unamplified. You might get some really faint sound out of a pair of lightweight headphones, but that's only because the headphones would have really tiny magnets.

In my experience, it isn't really dangerous to hook up headphones or speakers to a line-level output, it's just that you don't get any results if you try. The empeg may be different, I don't know.

Now, there's a such thing as self-powered speakers, and many computer speakers fall into this category. Such speakers accept line-level inputs with grace. But you must realize that such speakers are really two separate components bundled into one box: The amplifier and the speakers.

I thought there were several people here who had hooked their Pro's up at work. What, do you have receivers at work?

No, we either use self-powered speakers, or we use the LINE-IN jack on our computer sound card to mix the Empeg's audio with the computer's audio.

Personally, I do both. At home and work, I go into the line-in of the soundcard and mix the Empeg's audio with the computer's audio. It works great for listening to MP3s while working or playing Quake. At LAN parties, I plug my self-powered computer speakers directly into the Empeg, and use headphones to hear my game sounds. That way, the LAN party benefits from the Empeg but I don't give away what I'm doing in the game with sound cues.

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Tony Fabris