Suggestions for bookshelf speakers that have great dynamics, budget of $500 used.


So I really do not know where to start with bookshelf speakers as not been in the market for any for ever it seems.
This is for a second system where a pair of Monitor Audio Silver 3i are currently doing duty.
Room is largish and open but ultimate sq is not the aim as it is occasional use only, but when I do fire this rig up I usually like to play fairly loud.
Sources are many, fm radio, cassette tape, vinyl and streaming.
I have plenty of horses to feed them so even inefficient models can be considered.
Prefer to buy used as big savings to be had obviously and already broken in.
So suggestions around a maximum price break of $500 used.
Thank you in advance.
128x128uberwaltz
Nice suggestions all for sure.

I did buy the Vienna Acoustics Haydn as they were immaculate and even set up in very poor location at his house they really sounded good.

Will be giving them a long road test tomorrow.
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I heard the Haydns at a dealer quite some time ago. I thought they sounded very lush, somewhat warm, refined. Good looking speaker. Let us know what you think of them. 
Mesch
I cannot say as I would describe them as lush or warm but obviously a lot of that is system dependant.
I would say they are warmer on the very top end than the Silver 3i which is not a bad thing.
Mids sound about the same with vocals and acoustics being well detailed.
The bass might be a tad deeper but does appear to be more defined, especially as the volume is pushed where the Silver 3i could start sounding a little harsh and more "boomy"
Do not get me wrong the Silvers are mighty fine speakers for the money and I am talking louder than really comfortable levels and they are in a fairly large room.
Overall I am pretty happy with the Haydn,s.