I'm a tube guy but I wouldn't be in a hurry to find a tube amp for those under $2000. ;-) I used to own the Spendor LS3/5's and I found they mated well with a very well-restored vintage tube amp of around 30 wpc. I've heard other Spendors with similar vintage tube amps and receivers, and they worked nicely. You might keep your eyes open for a *professionally* restored Eico HF-87, or a Fisher or Scott receiver. Some Fisher 100AZ's would be lovely, or a Marantz, but $$$! And you need to know what you're buying. But as I said, don't just buy any old budget tube amp. Just my .02.
Advice on Sterling LS3/6
I learned on a UK Spendor forum that Derek Hughes is retiring and closing down Sterling Broadcast. They are clearing out inventory at excellent prices - mostly LS3/5a V2 and V3, but also a few other models. I'm looking at the LS3/6. The regular price for the LS3/6 is $6000/pair and the sale price is $3300 (plus $600 shipping to the US).
One pair of LS3/6 have been shipped to Jeff Stake, a dealer in Indiana. I told Jeff I may be interested, but I've never heard them. I could drive down to audition them (I live in Chicago) but I thought I'd check on Agon to see if others have experience with them.
I currently have Spendor SP3/5 R2 speakers in a small room. The LS3/6 would go in a new listening room, 17x23 ft. I will be using them with Bacch4Mac and a solid state amp (undecided, but probably Starcrimson monoblocks). Qobuz is the source, over a Bluesound streamer with LPS and English 8 switch. I'll use the Bacch's RME DAC. I like vocals (Melody Gardot), Argentine Tango (Gotan Project), Van Morrison, Duke Ellington. Seldom crank it up.
To my mind, the real alternative is a Harbeth 30.x or C7ES3. At Axpona I heard a Spendor Classic series (not sure which) that I really liked but the cost is beyond my budget (over $10k). Any comments would be welcome.
Latest review of the Stirling LS3/6 is from The Absolute Sound (where the retail price is listed as $9995):