I have 2 or 3 of them.
One is storage somewhere, still haven't picked it up.

They sound lovely, or the mid range does, tops are a little hard, i had the tweeters running on some Arcams which sounded better. But sadly they don't last, both of my 558's have faults, one is on its last legs.
The other in storage has a blown channel.

What you want is a 559, or 3
They sound almost the same, have done back to back testing, but sold the 559 as the 558 was 5% better sounding, but most people would never notice.
Oddly the 558 is very slightly louder than the 559, yet the specs show different, but again not much in it.

The 559s can be repaired far easier should they ever need it, 558s cost more to be repaired than just buying another.
Put in a search on Hifi shark for email alerts, same on eBay as they are like hens teeth to find, the 558 and 559.

My DSP5200.2s sound very similar to the 558's so wouldn't buy another or a 559.
Chord amps sound almost the same, but slightly better mid on the 558 / 559s, perhaps nothing some eq couldn't fix ? but the Chords are louder, more reliable and cheaper to fix.

Hope this helps a little.

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