Can you please tell me the model number of your CV towers? You may need a sub woofer dedicated on audio "OUT" of the line level on the Rec as CV's are usually inneficient speakers -- meaning they take GOBS of power to 'kick in" bass, as you have described. Please advise, thank you!

Wow oldies but goodies:) Problem is that your amp is rated (max) ~ 130 watts , "usable" ~ 90-100 watts. The speakers are more effecient than the new ones, but are still rated + 300 watts. So you are a bit under powered. As I mentioned, when trying to get the bass to "pump" at *normal" volume is pretty hard, unless you add a sub woofer (POWERED ONE) that has an indepenent amp, volume, crossover, etc. This way you can listen @ 30 % volume and kick up the sub, and when you "blast" the volume to get the CV's bass to kick in, the sub can 1) stay on, 2) trun off, 3) adjust volume to get a balance. This would be trial and error, but will work well to answer your question

Shame to waste the CV at higher volume, and as I mentioned, the sub would do work when YOU want it to. I would suggest a Best Buy or Wal Mart "sub trail" first, as if it works as I think it will in your set up, it will help determine if you want to swap out speakers as ypou suggested. If not , then you could use the return policy at the store to try a different speaker pair

Hello? Did this help answer your question as this chat is timing out

PURE power - modern stereo recevers can be limmited ~ 150 watts, you will want to see a THD rating of .01 % THD

What is your budget range?

Receiver power: Not all watts are created equal
Whether you go for a home theater or a stereo receiver, a couple of basic rules apply. Make sure that the receiver has enough power for the speakers you'll be using it with and the room you'll be using it in. The sensitivity of your speakers will help you determine whether a receiver is a good match — lower sensitivity ratings indicate power-hungry speakers that will require more "juice" from your receiver to produce the same volume as speakers with higher sensitivity ratings. Also, in general, the larger your listening room, the more power your receiver will need to deliver satisfying sound.

Evaluating power ratings
The benefits of increased amplification hardly end with sheer volume, though. All other things being equal, a receiver with more wattage will deliver more dynamic, detailed sound than a receiver with less wattage, even at low to medium volumes. But when you're comparing the power ratings of one receiver to another, bear in mind that not all watts are created equal. Some receivers employ more stringent guidelines in their power ratings than others. A full-bandwidth power rating is performed over the entire range of frequencies audible to human ears — 20 to 20,000 Hz — and is a more reliable indicator of quality amplification than ratings performed over a smaller frequency range (or those rated at just a single frequency, such as 1 kHz).

How "clean" is the power?
Another piece of the power rating puzzle worthy of note is total harmonic distortion (THD), which indicates how accurately a receiver can amplify music and movie sound. THD measurements for receivers almost always fall below 1%, so on first glance these ratings may seem to be almost indistinguishable from one another. But even small differences can be meaningful. The receivers with the cleanest amplification will typically have THD levels below 0.1%.

Want more sonic punch? Look for high-current power
The dynamic peaks that help make movie soundtracks and music so exciting can impose intense short-term demands on a receiver. High-volume special effects such as explosions or loud orchestral passages can quickly deplete a receiver's power reserves, resulting in sound that's flat and uninvolving. Models with high-current power are particularly well-equipped to handle these challenges, reproducing dramatic surges of sound with more punch and greater fluidity than other receivers with similar wattage ratings.

Here is a link to a high current, high end Harman Kardon HK 3490 120 Watt Stereo Receiver which has higher CURRENT (bigger power supply) than the 130. http://www.amazon.com/Harman-Kardon-HK-3490-Receiver/dp/B00198F89A/ref=sr_1_1?ie=UTF8&qid=1336262911&sr=8-1

Receivers have tuners for AM/ FM, wheras AMPS have INPUTS for a "tuner" if desired. The amp is a basic L/R Line level input that has input selections for your audio sources, IF you are not a radio "guy" put your $$ into a high current amp

Continuously Variable Loudness Control
Yamaha’s exclusive Continuously Variable Loudness Control enhances stereo listening at low volumes, so you can enjoy all the richness of your music at any volume level without sacrificing detail.

Traditional Amplifier Design Meets Next-Gen Connectivity Here is a link for you -- 85 PURE watts vs 130 "fake" with the ciruitry that will (enhance) the loudness (bass in particular) and across all frequencies as well.

http://www.amazon.com/Yamaha-A-S500BL-Integrated-Theater-Amplifier/dp/B0044779HW/ref=sr_1_5?s=electronics&ie=UTF8&qid=1336263910&sr=1-5

Bluntly, the Sony does not have the balls to compete at this level -- again high current + variable loudness = *what I believe* is what you are looking for without breaking the bank, IMHO.