Hi and welcome to the forum.

There's been some discussion on this in the past.
Try a Google Search of the forum (see link top of this page) for "DSP5000 V DSP5500" that yields a few hits.

In summary DSP5500 are much more powerful than 5000, but the bass can be difficult to tame esp. in a small room.

The 24/96 versions command a high prices over the 18/48 versions. if you wish to use with hi-res audio you will need the former.

What size room will there be used in?

Regards,
Carl

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