rharv is correct in that you should think about the playback systems for your slide shows. Are you simply going to provide these online, or will they be shown using PA systems for playback or in movie theatres with a full multi-channel surround system, etc.?

If you cannot specify the playback system, then more important is the orchestration and arranging; not the EQ settings.

rharv again is right that the voice-over should be handled by either ducking, or manual volume envelope adjustment of the music tracks in the video editing suite that is being used.

If you are just shooting for the 'distant' kind of a sound, an easy way to do that is both with volume as well as EQ. Just put a fairly steep downward to the right slope on an eq to simulate a sound coming from a distance - coupled with a decrease in volume.

High frequencies attenuate in air more rapidly as a function of distance, than do lower frequency content. This is why distant thunder sounds just as a 'boom and rumble' while thunder that you hear from a nearby lightning strike has all the 'crack and snap' in it as well as low frequencies.

But likely this is not exactly what you want to accomplish - particularly if your soundtrack will be played over laptop speakers, which have nearly no low end capability.

What is the type of slide show, where is it played, etc. help to determine the type of orchestration and arrangement needed.

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