Here is the complete KLH list in order

Model Woofer size Tweeter Size Crossover Freq
Six (139.95) 12 1 3/4 1.5 KHz
Five (199.95) 12 1 3/4 600Hz and 2.5KHz
(the Five is a three-way with two 3 inch mid range speakers)
Twenty-three 12 1 3/4 1.5 KHz
(The 23 was described by some as the successor to the Six, but both were sold
at the same time (159.95)
Thirty-Three 10 1 3/4 1.5 KHz
(99.95)
Seventeen 10 1 3/4 1.5 KHz
(79.95)
All of the above appear to share the same cone (direct radiator)
tweeter and have identical crossover frequencies with the exception of the three-way Five
Thirty-One 8 1 7/8 1.8 KHz
(89.95 the pair)
Thirty-Two 8 1 7/8 1.75 KHz
(110 the pair)
Thirty-eight 10 1 7/8 1.75 KHz
(135 the pair)
These latter three appear to share the same cone tweeter. The difference in crossover frequency (1.8 vs 1.75) may simply be rounding error in the sales literature


David