Cary have a bunch with ht bypass.
I have a slp 2002 with a true HT bypass. I can even turn off the unit to save tube life in HT mode. It has 3 sets of speaker outs (2 rca, 1 xlr). I use one of those sets as a sub input. All that is needed is a crossover on the sub.
Many pre's with HT bypass aren't a true bypass. They use unity gain but still process the signal.
Good luck.
kw.....
I have a slp 2002 with a true HT bypass. I can even turn off the unit to save tube life in HT mode. It has 3 sets of speaker outs (2 rca, 1 xlr). I use one of those sets as a sub input. All that is needed is a crossover on the sub.
Many pre's with HT bypass aren't a true bypass. They use unity gain but still process the signal.
Good luck.
kw.....