Subwoofer with RTi12's

beavis814

Hello. I'm new to Club Polk, and this is my first post.

I recently ordered my first pair of Polk speakers (Rti 12's), and thanks to Polk's holiday promotion, I will be receiving a free subwoofer (PSW10). As I was looking at the specs on the subwoofer, I noticed that the lower end of the overall frequency response and lower -3db limit of the 12's, which is 18Hz and 30Hz respectively, is better than the lower end of the overall frequency response and lower -3db limit of the subwoofer, which is 35Hz and 40Hz respectively. Currently, I do not own a subwoofer, and I'm just wondering if it would make sense to hook-up the sub given the specs listed above. From the research that I have done, it looks like an SVS or HSU sub is the way to go, and I plan to purchase a sub from one of those companies at some point in the future.

Thanks in advance for your feedback.

jdhdiggs

Welcome oh great Cornholio:

Make sure you have a high quality, dedicated amp first.

If you do, do not unpack the sub as it really won't help the low end. I would sell it, take the ~$120 and use it towards a more sizable sub.

If you don't have a strong amp, I would probably still sell the sub and buy a high quality amp with the $$$.

My last choice would be to keep the PSW10. The only reason that I would do this is if you need bass right now and you are running the 12's off of a lower end reciever.

The reasoning for getting a very strong amp is bass needs power, the lower you go, the more power you need. For the 12's, a 300W/channel amp would be the minimum I'd recommend if you are running them fullrange.

If you don't have enough power, two things can happen:
1). your dynamics suffer since enough current is not available to keep up with the signal
2). Clipping, which is your amps is maxed out and sends a high current DC signal through the speaker blowing the tweets.

Another power solution would be to bi-amp, using your reciever for the tweets and a seperate amp for the woof section.

Those are my thoughts, take them as you may. Hope it helped!

AsSiMiLaTeD

Well the best way to know for sure is to hook it up and see, but....

I doubt you'll gain any advantage by hooking up that sub with those speakers. I'd sell it and get an SVS.

I hope you've got plenty of good power to drive those 12s...a receiver won't cut it IMO, you'll need a separate 2 channel amp to get the full potential of those speakers...

Welcome to the club

Willow

Welcome....those are some big A$$ speakers....as stated a reg amp will not work well you need lots of juice for those puppies.
You can plan ahead aor buy for now......plan ahead if you will get surrounds....you can keep the sub for them...or you can sell your sub and buy a new one...as you mentioned SVS or HSU...or both keep the sub run it woth the fronts set to small and buy a new one in a bit......if you don't see yourself buying an amp to run them then return them buy the 8's or 10's with the $$saved you can buy a new sub...

Mjr7531

Enjoy the RTi12s, tell us how they are I've been planning to purchase them sometime...
When using the RTi12s in leui with the Subwoofer (whichever it may be) I would not suggest setting the 12s to small, I remember reading somewhere on this forum that the woofers are crossed over at 120 Hz (right guys?) and to use bass management would leave them half-inoperatable.
My 2 cents, good luck with em',
Matt

bigsexy1

Originally posted by Mjr7531
I remember reading somewhere on this forum that the woofers are crossed over at 120 Hz (right guys?)

That is right, if memory serves me correctly.

Sell that Polk sub, use the money to help towards a better sub or amp for the 12s.

beavis814

Thanks for all of the advice! I knew when I ordered these speakers that I would probably need to buy an amp to properly drive them. I've started looking on Audiogon and Ebay for a good deal on a used amp. Hopefully I can find a 5-channel amp that puts out 200 watts/channel so that I can bi-amp the 12's and still have one channel available for the center. So, I'll sell the sub and add the proceeds to the budget for an amp.

Thanks again!

VR3

Look up Outlaw Audio

www.outlawaudio.com

Willow

didn't know about the xover....in that case I would't even use the sub...set your mains to large leave the sub in the box and sell it

jdhdiggs

Originally posted by beavis814
Thanks for all of the advice! I knew when I ordered these speakers that I would probably need to buy an amp to properly drive them. I've started looking on Audiogon and Ebay for a good deal on a used amp. Hopefully I can find a 5-channel amp that puts out 200 watts/channel so that I can bi-amp the 12's and still have one channel available for the center. So, I'll sell the sub and add the proceeds to the budget for an amp.

Thanks again!

If it's only a 2-channel setup, that's some serious coin. Look out for some 350+W/channel 2-channel amps. You'll get some better bang to your buck IMHO.

Early B.

Yeah, forget about bi-amping them and just get a good 2 or 3 channel amp.

Mike Reeter

I have the 12's and an SVS PC-Ultra Sub...In heavy LFE tracks,that combination will kick some serious butt...

Enjoy the 12's,sell the sub,save up for a GOOD subwoofer,and an external amp.,you won't be sorry...I guarantee it.

AsSiMiLaTeD

I wouldn't bi-amp those speakers...

The problem with Bi-amping is that you're dictating to the speaker how much power is used on each driver, instead of letting the speaker decide.

For example, let's say you bi-amp with 100 wpc on the highs and the lows. You're still giving the speaker a total of 200 WPC, but you're limiting what it can do with the power. So if you have a scene with LFE at a high volume, the speakers will need more than the 100 watts you're giving the lows. So the best thing to do is just run only one amp, so the speaker can allot the wattage in a more practical manner, maybe giving the lows 150 watts and the highs 50...The mids and highs typically use alot less power than the lows, hence my point.

beavis814

Sounds like some good technical reasons not to bi-amp, and I get the impression that it is more economical too. So, off to hunt for a good two channel amp!

Kano

Would a high end receiver not be able to run the 12s? Such as the Harman Kardon AVR7300, with 130W (Tested not rated) surround and 140W stereo, they would still be lacking? How DO those speakers sound with 500W pumping into them?

jdhdiggs

With 140W you will go deaf before you blow your speakers, but low frequency transients will drag. The more powerful the amp, the stronger/quicker/more authorative the bass will be. When I ran my RTi800's (Not the worlds most power hungry speaker) on a reciver tested at 100W/channel, they sounded ok. Hooked up to 300W of power, they sounded very good, mush crisper and clearer with a bit better imaging.

Early B.

Would a high end receiver not be able to run the 12s? Such as the Harman Kardon AVR7300, with 130W (Tested not rated) surround and 140W stereo, they would still be lacking? How DO those speakers sound with 500W pumping into them?

The wpc is only one factor to consider. Receivers, by their nature, have multiple roles to play and don't do all of them efficiently. Typically, a good dedicated amp, even if it is rated with lower watts than a receiver, will have higher quality parts, provide cleaner power, and drive speakers more efficiently. This translates into better sound. So yes, a high end receiver could run the 12's, but not as well as a dedicated amp. A separate amp will provide the "slam" and better bass that the 12's can put out.