Line level or speaker level, scientific reasons? ?


Hi everyone, I've been hearing a lot on the forum that it is better to connect through line level from pre-amp to the sub. Now my connection right is using the speaker level connection and I think it sounds great. I am using bookshelf speakers and by using speaker level inputs I am able to remove the lower frequencies from the mains!

Wouldn't this be a huge benefit than running the full frequencies to the speaker? It frees up the amp to provide more clean power!

now what is better and why?!!
mrhdream
Using speaker level to the sub then to the mains is an extra drain on the amp and the filters may keep things from blending well.

I like using line level better. This allows me to use all 17 watts to my mains and a good quality sub/sub amp combo. I honestly use a Janus Interphase 1/A sub amp/crossover. This allows for virtually transparent crossover at 100hz, loads of power to the sub(pair of nelson reeds) and never interferes with the amp or pre except for being in between them.
Just an FYI...what Elevick describes is NOT how a REL is setup or how it works. It is parallel to the main speakers and is self powered. It takes nothing from the amp, but the signal; just like the sub getting the signal from a second pre-out.
Yeah my experience with Rel's is that they do seem to work best in parallel from the speaker level connections off the amp(speakers, whatever). Hey, if it works, don't mess with it, ey?!!
Running in parellel is the cleanest way but not always the sonically best. My beef is that running in parellel will not always blend well. You can set the sub volume at a certain level and have it match great but once you change pre-amp volumes, many times your blend won't work as well simply due to efficiency differences and a difference in amps between the sub and main amp. Yes, you can have a remote volume for the REL but who wants to keep messing with sub volume?
I have to agree with Elevick that it has been a little difficult to find a perfect blend. It seems at some frequencies it's perfect, yet at others it is noticeably that there is a sub providing extra juice. I"m going to try and mess with the crossover and phase setting to see what may help.