Buying speakers ten or more years old a good idea?

The L-R speakers that anchor my HT are Mirage M5si's, bought 17 years ago. I have no intention or reason to replace them. Ivan_nosnibor's post has some good advice I need to follow: redo the crossovers and top off the ferrofluid in the tweeters.

Crossovers: A few years ago I was using a 5-channel Adcom to biamp the Mirages and to power the center channel. I kept blowing a fuse, and an ohmmeter indicated that something was wonky with the individual halves of the crossover, while the full crossover presented a reasonably stable load. I went back to bi-wiring, but the blown fuses do point to a crossover problem.

Tweeters: When I run my pre/pro's automated speaker setup, the white noise indicates some differences among the four tweeters (they're bipolar) in the M5si's. While that may also point to the crossover problem, it may also be the ferrofluid (assuming my tweeters use it). So anyway, I am overdue to take those in for some maintenance, after which I will REALLY have no reason to replace them.

mine are almost 20 years old. i purchased them $1100 and so far replaced one woofer $450, but it was my fault for cueing needle onto record, but forgetting to mute preamp :-). this plus the age of speaker played the bad part.

i'm still a happy camper because for the modern speakers of the same class i'd had to be within 5 figures minimum.
makes sense eveneven if you have to service them. just make sure that parts are available. buy ones with existing service.

vintages such as ohm, aerial, klipsch, jbl, tannoy, alon, vandersteen, snell are not any worse than modern ones at the fraction of price.

you may also optionally want to replace damping material if the one is being used with fresh one and properly tighten up bolts for each speaker driver onto the cabinette. clean the terminals with deoxidising solution and perhaps reapply fresh solder onto the crossover parts and driver connections as these are directly exposed to vibration and within the time become dry cracked and cold.

Earlier this year I pulled a pair of Sound Dynamics 300ti's from around the mid 1990s that had been stored (boxed) since 2001, part of that in a garage that got down as low as 36F in winter, and they sounded quite good, pretty much as I remembered them. Surprised me.

Acidfolk,

As you can see, there are many great used speaker options.

As to the amplifier requirements of the Thiel 3.6's and above, I think
Mcloughlin's description of his upgrade path says it all. You can get by with
250 very high quality watts, but more just gets you better results with the
Thiels. Classe is a good match (I used several) but I would also
recommend a tube preamp.

If you're budget is meager, I can recommend an excellent 400-watt
amplifier that can be had for under a grand; the Musical Concepts Hafler
500. It actually beat my old CA-2200. I know somone who has an extra one
should you ever decide to go that direction. It has one of the best midrange
blooms I've ever heard and the Thiels LOVE midrange friendly amps.
Finding the right amp for any speaker you decide to buy will be critical to
getting a satisfying sound.

No bad idea.