Originally Posted by
HCSGuy
Your question could be answered two ways. First, what hookup method would best match the designer’s intent when the speaker was built in the early 90’s, and second, what sounds best for how you use the speakers now?
To answer the first, these were designed at the beginning of surround sound - no matching center speaker was ever made for them. If you think of them as music speakers, and you are trying to get the original sound out of them, do not use any additional crossover - the speakers have a 180hz non-defeatable passive crossover built in. One option would be to connect the HK amp to the front (full range) preamp outputs of your receiver, let the passive crossover cut everything starting at 180hz, and hopefully the HK amp has gain controls that you can use to balance the bass to the rest of the system. If not, second option would be to let the HK run the speakers full range - connect it to the front preamp outputs of the receiver, then put the bi-amp straps back on, disconnect the receiver speaker leads from the speakers, and just use the HK amp to power the L7’s. This will probably be your best bet for music sound quality.
However, the woofers in the L7’s go pretty low, and take a lot of power, so if you’re using them in a surround sound video system, why not treat them as a subwoofer and LCR in one cabinet, which is what you are doing. Without opening them up and bypassing parts of the speaker, the 180hz crossover point will remain, so you’re going to have to do some experimenting. If you don’t have a separate sub, and are using the L7’s as subwoofers, you can set the crossover closer to 80hz on your receiver, and connect the HK amp to the sub out on the receiver as you are doing. This does leave you with two cascaded crossovers, but since we usually crank up the gain on subwoofers, the actual output one octave up, at 160hz, may still be close to what you would get in example one, so you may not hear a “Suck out”. If I was doing this, I would probably still configure the front speakers as “Large” on the receiver, and set the subwoofer output to LFE+L/R, so that the bass output is duplicated, even though the top half of the L7’s will still start cutting the bass out of the 8” mid-bass at 180hz (probably at 12db/octave). This is probably the way you have it now, so put some well recorded music on and do some listening, and tweak as necessary.