Need some Amp help - a little new to properly powering speakers


Hello. 

 I have some polk LSIM707s that I thorough enjoy.

However, at the moment I'm powering them using a Yamaha aventage 3070 receiver which at 150 watts at 8ohms sounds pretty darn good. 

However, since these are rated at 300 watts at 8 Ohms, I assume I will need some more power. I notice at lower volumes a lot of the imaging and clarity disappears. 

I am looking at buying a 300 watt emotiva Amplifier, or a 500 watt emotiva amplifier.

I'm assuming it would be better to purchase the 500 watt per channel emotiva so the speakers won't suck it dry or stress it. 

Am i wrong in this assumption? 
moskaudio
Tim,
We have a similar assessment of moskaudio's current audio system. The speakers are pretty decent and will respond to better quality amplifiers. The Yamaha receiver is the relative weak link in this system. Evidence is that  lower level sound quality improved noticeably when the Rotel replaced the Yamaha. I do believe that moskaudio has recognized the necessity for moving toward a amplifier of "higher quality ". There’s more potential with the Polk speakers to be gained.
Charles
Hello moskasudio,
   Let me start of by stating that my technical knowledge can be fit into a thimble,and still have enough room for a thumb!  That being said,how large of a room are you listening in? Also,how far are you seated from your speakers?  That information should be quite helpful. 
      
       Ray
The very first thing you need to know is that wattage rating on loudspeakers tells you exactly zero about how they sound.  All it tells you is that if you exceed that wattage, you can fry your loudspeaker.  

I think your current setup is actually quite well matched.   People who reside on the Audiogon forum will pretty much universally dislike both Japanese receivers and Polk Audio loudspeakers, but if you enjoy what you're hearing, then keep enjoying them.

If you really want to move up, then begin by listening to as many other loudspeakers as you can.  Visiting the local audio showrooms is OK, but your best bet is to meet other local audiophiles and listen to what they have.  Learn why they made the choices they did, both in loudspeakers and amplification.  

I have plenty of opinions myself, but what you really need to do is get more experience with the gear others own.  

Moskaudio

The Aventage 3070 is a wonderful amplifier, for stereo or H/T use. It will have plenty of power right through the range to drive your 707s. I would make sure you have checked your cable (what type is used?) polarity. Have you run the Yamaha Audessy calibration?

Before outlaying more money, check thoroughly what you have. I note AudioGon does have excitable contributors with views on SS or Valve or Brand, but you already have good gear. Have a professional from a store (or otherwise) to look at it first...just my 2 cents....

AMG

moskaudio

 Impedance reaches a minimum of 3.75 ohms at 66 Hz and a phase angle of –47.96 degrees at 83 Hz.
Read more at https://www.soundandvision.com/content/polk-lsim707-surround-speaker-system-ht-labs-measures#fIW7rJB...
This indicates for them to sound their best in the bass, an amp that has good current delivery <100hz.
A good solid state amp that can keep increasing it’s wattage for every halving of impedance, is an indication that it can deliver current.

EG: A theoretically prefect amp that delivers current, none can do these prefect figures in real life, but some get close.
8ohm 50w
4ohm 100w
2ohm 200w

Cheers George