Amp advice for Polk RTi A9's - AVS Forum
Forum Jump: 
 
Thread Tools
post #1 of 9 Old 08-31-2012, 02:55 PM - Thread Starter
Member
 
jdustinb's Avatar
 
Join Date: Jul 2012
Location: Seattle, WA
Posts: 60
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Recenlty acquired some RTi A9's for a 7.1 setup (Polk RTi A9, CSi A6, FXi A6 and some old RT3000p monitors in the back) on a Denon AVR-3312ci. I can already tell the A9's are power hungry, much more than the receiver is capable of providing. HT Labs measurements for the receiver:

Seven channels driven continuously into 8-ohm loads:
0.1% distortion at 79.5 watts
1% distortion at 96.8 watts

Yet A9's are rated for 50 - 500w. The question is, where do I begin for amplification. I've got the preouts and I've read a lot about Emotiva Amps. The XPA-2 seems like a nice choice to power the fronts and I've read enough where I'd prefer to go that route for the fronts over the XPA-3 or XPA-5 (plan to add additional amplification for the rest down the line anyway). On the flip side, I've also read that Emotiva is generally considered good entry level, but that there are higher quality used amps out there to do the job for the same price or less.

I found a pair of local used Rotel RB-980BX amps, which when bridged can be 360w mono for about half the entry price of an XPA-2. I know there are more specs to be looking at than just pure wattage, but some insight on some good used amps, either mono or multi-channel, would be much appreciated.

To throw another idea out there entirely, I'm also interested on thoughts about using a tube amp to power these. My listening habits are pretty evenly dispersed between movies/gaming/music.
jdustinb is offline  
Sponsored Links
Advertisement
 
post #2 of 9 Old 08-31-2012, 05:22 PM
585-645-1006
 
jdsmoothie's Avatar
 
Join Date: Sep 2007
Location: Orlando, FL
Posts: 42,801
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 267 Post(s)
Liked: 1300
Where do you usually set the master volume on the 3312CI?

---------------------------------
"JD" – jd@avscience.com ; shop.avscience.com ; 585-645-1006, AVScience - AVSForum sponsor for 15 years  
Mon - Fri: 8am – 8pm EST (Sat/Sun, leave message)
Call for pricing on Denon, Marantz, Yamaha, Onkyo, Klipsch, Def Tech, Oppo, Parasound 
** Think the AVR is defective?  Reset the microprocessor 4-5 times. 
jdsmoothie is offline  
post #3 of 9 Old 08-31-2012, 08:35 PM - Thread Starter
Member
 
jdustinb's Avatar
 
Join Date: Jul 2012
Location: Seattle, WA
Posts: 60
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
^^ it depends on the time of day, if others are around, and what kind of content I'm watching/listening/playing. anywhere from -50db for mellow to -10db for movies and listening to music while futzing around the house. anything above that is likely too much. I'm under the impression that if I had more power, clarity would be better even at lower levels.
jdustinb is offline  
post #4 of 9 Old 09-01-2012, 01:11 AM
585-645-1006
 
jdsmoothie's Avatar
 
Join Date: Sep 2007
Location: Orlando, FL
Posts: 42,801
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 267 Post(s)
Liked: 1300
Then you don't need to add an amp.

---------------------------------
"JD" – jd@avscience.com ; shop.avscience.com ; 585-645-1006, AVScience - AVSForum sponsor for 15 years  
Mon - Fri: 8am – 8pm EST (Sat/Sun, leave message)
Call for pricing on Denon, Marantz, Yamaha, Onkyo, Klipsch, Def Tech, Oppo, Parasound 
** Think the AVR is defective?  Reset the microprocessor 4-5 times. 
jdsmoothie is offline  
post #5 of 9 Old 09-01-2012, 07:04 AM - Thread Starter
Member
 
jdustinb's Avatar
 
Join Date: Jul 2012
Location: Seattle, WA
Posts: 60
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
That just seems like too much conventional wisdom right there. wink.gif I will say that it doesn't seem like the speakers have enough headroom in the bass department when listening at -10db though. Thoughts?
jdustinb is offline  
post #6 of 9 Old 09-01-2012, 09:58 AM
Senior Member
 
SMO5007's Avatar
 
Join Date: May 2010
Posts: 226
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 15
JDustin:
I have the a9's running off of an xpa2. Csi a6 and polk surround rc85i in walls running off of xpa5. Current AVR is Denon 4308ci. When I switched from the internal amps to the XPA's there was an immediate boost in sound quality. I definitely think that you should go the xpa2 for the a9's and xpa3 or xpa5 for the rest of the system. You will not be disappointed. Trust me when I say this......
I started first with the xpa5. Hooking that up for the first time was in other words "couldn't believe what I was hearing." Im not BS'in you. The headroom plus overall sound quality was top notch.

Then I added the xpa2 because I listen to a lot of two-channel music. I wanted to see if I could bring my music listening to another level. The xpa2 didn't fail. I noticed better imaging, greater headroom, overall a step up in sound.

The Denon you are using currently doesn't quite have the amp section and/or power reserves to properly power our speakers. You are taxing the **** out of that amp when listening to -10 levels.

Since you have the pre-outs you are ready to go. Give the xpa amps a try!! If you have any questions don't hesitate to ask!!

Denon 4308ci
Pioneer DVD/CD player dv-59avi
Panasonic DMP-BD60
PS3
XPA2
XPA5
Polk RTi A9's
Polk CSi A6
Polk RC85i inwalls
Velodyne ct-120 replaced woofer with diamondaudio 12" macdaddy
Sony KDL-55hx800
SMO5007 is offline  
post #7 of 9 Old 09-01-2012, 12:11 PM
Member
 
lapaynem4's Avatar
 
Join Date: Nov 2009
Location: Tn.
Posts: 22
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I recently started using a Crown XLS 2500 on my Polk Rti 12's and the difference in bass output was dramatic.
It seemed to tone down the brightness a bit, and I think overall sound quality is much better.

I would definitely recommend you to get an amplifier. Hope this helps.

Onkyo TX-NR709
Onkyo C-7030
Crown XLS 2500

Polk RTi12's
Polk CSi3
Polk FXi3's
Polk PSW-505's
lapaynem4 is online now  
post #8 of 9 Old 09-01-2012, 05:43 PM
585-645-1006
 
jdsmoothie's Avatar
 
Join Date: Sep 2007
Location: Orlando, FL
Posts: 42,801
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 267 Post(s)
Liked: 1300
Quote:
Originally Posted by SMO5007 View Post

You are taxing the **** out of that amp when listening to -10 levels.

Not quite, and especially not if there isn't any distortion heard.

---------------------------------
"JD" – jd@avscience.com ; shop.avscience.com ; 585-645-1006, AVScience - AVSForum sponsor for 15 years  
Mon - Fri: 8am – 8pm EST (Sat/Sun, leave message)
Call for pricing on Denon, Marantz, Yamaha, Onkyo, Klipsch, Def Tech, Oppo, Parasound 
** Think the AVR is defective?  Reset the microprocessor 4-5 times. 
jdsmoothie is offline  
post #9 of 9 Old 09-04-2012, 01:51 PM - Thread Starter
Member
 
jdustinb's Avatar
 
Join Date: Jul 2012
Location: Seattle, WA
Posts: 60
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by jdsmoothie View Post

Not quite, and especially not if there isn't any distortion heard.

Thanks, guys. It seems that while these speakers don't require a huge amount of power to make sound, they do seem to require a decent amount of power to properly drive and bring out the detail and imaging they're capable of.
jdustinb is offline  
Reply Receivers, Amps, and Processors

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off