Bodyblue

If you have not joined AudioKarma, think about it. There is a great diversity of opinion over there. Older speakers like the KLH 6, especially ones that have not had any work done on them are not really the best for tubes, truth be told. Tubes have what is called "warm" sound. It is a type of distortion that many find pleasing to their ears and that is why it is so popular......but not nearly as popular as solid state. Older speakers with no fresh caps and tubes simply wont give you the best sound. "Warm" can easily become muffled highs and in lower power amps, lack of bass. I like tubes even though I dont find them worth the trouble. I prefer the clean sound of solid state, especially with older speakers. I have three systems going all the time (4 with the HT) and all use vintage speakers (KLH 6, Marantz Imperial 6, Nova 7Bs, OLAs, Nova 8Bs, Polk Monitor 10s etc) that have been recapped with a few sets with fully rebuilt woofers. Want to really hear what your KLHs can do? Like the poster above said, give them 100 wpc from a SS amp or receiver and then judge.

Where did you get the idea that you had to power them with a tube amp or vintage receiver? Of course they sound fine with lower power stuff but I have found my 6s (and my Large Advents and all my other acoustic suspension speakers) sound better with more power rather than less. My set is different than most 6s since after one woofer was blown apart by a crappy Darlington power pack I had both rebuilt. A local speaker repair company (a one man outfit) used his 3D printer and some Advent foam to create new surrounds out of modern foam. The result was a much better sounding speaker with much faster bass. I appreciate tube amps but I prefer clean SS sound, especially with older speakers with paper cone tweets. I have owned over 40 receivers and still have a few. When they were new, almost any of the mid to higher end units sounded great. Now that they are 40+ years old, the best way to choose a vintage unit is NOT the brand, but the condition.