Adding a sub woofer?


Running a Planar 6 to Icon Audio Ps1 Mk2 to Quicksilver Mid Monos into Klipsch RP8000F speakers. Want more low end, thinking of adding a sub. The mono blocks don't have a dedicated sub output so I was thinking about something like a PSB 250 which has both pre amp and speaker level inputs with speaker level outputs. A couple of questions.

What are the pros and cons of using the sub's preamp level inputs vs the speaker level inputs in this application?

And more importantly, right now my setup is pretty much tube analogue the whole way (and aside from the soft low end, I absolutely love the overall sound) - but does an inline sub like this do any processing, will it color the mids and highs in some way or is it just a clean pass-through in terms of sending the signal along to the speakers? 

Thanks for sharing your thoughts. 
Ryan
spotconlon
Hi Ryan,

Depending on how large your room is, what types of music you like to listen to and how loud you like to listen to it, a single PSB 250 or even two maybe too small.

What are the pros and cons of using the sub's preamp level inputs vs the speaker level inputs in this application?
 
In this case the pre level Inputs would allow you to use the PSB 250's low level input and output connection scheme that limits the level of the low frequencies reaching the mains. This setup would give you the most control and should be far easier to integrate than the other hookup methods.

does an inline sub like this do any processing, will it color the mids and highs in some way or is it just a clean pass-through in terms of sending the signal along to the speakers?

I did not read the owners manual all the way through but at the price point of the PSB 250 I highly doubt that there is any processing happening so it should be a clean pass through to your mains with the exception of the limiting of the level of the low frequencies below your chosen crossover frequency.

You may also need to plug the ports on the RP8000F's to get the best results. 

I noticed that the RP8000F's can be  Bi-amped. You may get satisfactory results with this option also if you can control the input gains of your amplifiers.  
Thanks Rusty - helpful. And thanks all for your comments - plenty to dig into here, lots of homework. I appreciate all the thoughtful ideas and suggestions.
SVS SB3000! I have this and a Sunfire HRS12 that seem to play very nicely together - both musical, accurate and DEEP... 
Hello,
I just added a pair of REL T9s to my system. The T9s are active/ amp driven down firing with a passive front firing driver. The T9i or newest model is the opposite with the front firing driver is active/amp driven and the down firing is passive. I feel the front firing is a better design for music.  I like to use a pair of subs for the front. If you choose to go with a speaker terminal connection or speakon please call the manufacturer for setup. Differential balanced or mono blocks require a special termination due to the type of ground connection when connected to the speaker terminals. ( Very important so you don’t damage your other equipment.) I also prefer a sealed enclosure for music instead of a ported enclosure. HSU has a unique enclosure that lets you block the ports to turn the ported enclosure to a sealed one.  Ported or holes in the enclosure go down deeper in frequency but the bass has less control. Great for movies to shake the room. Home theater works better with the ported enclosure to shake the room and can cost less per lower Hz frequency.  I am doing two subs L/R for the front and a ported enclosure for the surround sound connected to the LFE /RCA connection on the surround sound receiver. Also sealed enclosures are usually very fast to help match to the front speakers especially RELs. Since you usually have only one active driver per sub I believe it sounds better to have two to match or add to your left/ right front speakers. Also this is much more balanced since you are setting the sub on the side of the speaker you are trying to improve. By adding more subs you can meld the subs to the system easier since you can turn the volume/gain on all the subs down to prevent the boom. That is why I like a separate ported sub for movies usually on the side wall in front of the seating area. I will probably get two more T9i RELs for the front and move the T9s / down firing to the rear of the room later. Sorry for the length of this post. Subs have a lot of detail to explain. When you decide to get a sub look up sub crawl to help set it/ them up. 
I added a pair of HSU ULS-15 II subs to my Cornwall IV speakers. I am running the CW full range and bringing the subs in @ 35 Hz. I can very much recommend the HSU  brand, these things integrate perfectly with the main speakers and are unobtrusive unless called upon for duty.

Oz