Ahhh--Problem solved. Adding a REL sub-bass unit...


I'm wondering how many audiophiles have given up on loudspeakers preamturely, or have gone down the rabbit hole of cable swapping to "fix" an issue with their speakers.  

I grew up hating subwoofers and home theatre.  I still haven't come around fully to home theatre.  I've warmed up though.  I've had my own issues with otherwise great loudspeakers, including a pair of Klipsch Forte IIIs.  I was very frustrated as I'm feeding them from a respected tube integrated, I've tried them with a 300B amp, and I've toiled over positioning.  

The issue that I was having was the mids and highs were dominating in my room--despite the size of the woofer and passive radiator. Some recordings were just too bright.  Sometimes I felt the speaker, however "alive" and dynamic was not imaging well, needed soundstage help, and so on.  

I hate to say the REL T9i I threw in the mix today is a panacea because there's always stuff to tweak.  Yet I have experienced this before with a Sumiko subwoofer.  Adding one to the mix and dialing it in so that it's barely audible has brought everything into focus.  Everything is more relaxed and energetic at the same time.  

I'd say that the REL is a room tuning device above all.  I have a larger room (I think it's 15 wide, 24 long and 10 high--in feet).   I'm not sure how much I'd have to spend or what different choices would solve this otherwise.  From a guy that used to reject subwoofers out of hand (my bias came from the 90s home theatre craze) I think that they might be necessary in the lion's share of systems with the lion's share of speakers.  To say, "you don't need a sub" with speakers might be true depending on your room, but I also think in most situations you are missing out on what they can do for so many criteria that are not necessarily in keeping with adding bass--e.g. soundstage, focus, imagine, fullness, taming treble, etc.). 

Finally, I really wish that I could try some other brands as many audiogon members recommended so many respectable names.  I ultimately went with REL because of its philosophy, my similar experience with a Sumiko sub (within the family of REL or somehow related), and the high frequency input connections. 
128x128jbhiller
I said "I like 1st order high pass on the main amplifier" - that means that you roll the low end out of the mains.

A single capacitor in series with the amp input works beautifully.

If you do this with the REL you are not using the high level speakon connectors, no?
RELs are specifically designed to have the mains run through their entire frequency range. REL's manual highly advises to only use the high level speakon connector because it performs the best in that way. (I have tried REL subs using the high level connector and not using the high level connector.) This does not mean the REL doesn't provide flexibility. But it does mean it is designed to fully integrate with the mains by taking its timing cue/signal from the same amplifier was the mains, without deriving its power from the mains' amplifier--the concept being that the mains amplifier allows the REL subs and the subs to be "colored" with the same signal. The RELs allow the user to crossover from 30Hz to 120Hz, to select "0" or "180" phase and to control volume/gain. REL recommends running their subs at the lower end of the crossover range and at a  relatively low volume. I'm currently running a three REL "swarm"--it works really well.    
2 things I am thinking about with REL:

1.)Will it go low enough for my liking? (I don't get the warm and fuzzies from only going to 28Hz on the T/9i
2.)Would I be better off, as in, better integration integration with my mains if I went the Vandersteen approach and used the low slope high-pass filters combined with the high-level speaker connection with a 2wq. Not only that, but the 2wq hits to 20Hz and is considerably heavier and is also known for being an extremely musical sub.
It seems like I might be better off with the Vandy, but I get the feeling I shouldn't discount the RELs (They are somehow calling my name, LOL)