Mixing Emotiva XPA-3, Adcom GFA-5500, and Onkyo NR-708 - AVS Forum
Forum Jump: 
 
Thread Tools
post #1 of 13 Old 03-03-2012, 12:29 AM - Thread Starter
Member
 
Teseract's Avatar
 
Join Date: Jan 2011
Posts: 125
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
So I'm planning on an Emo XPA-3 whenever the Spring sale rolls around. I currently have an Adcom GFA-5500 with an Onkyo NR-708 receiver. Front speakers are Polk RTI-12's with a CSI5 center, a couple Sony towers for surrounds that I've modified with inexpensive crossovers (stock just had caps inline with the wires) and better tweeters/mids, with some stock Sony bookshelf speakers for rear surrounds.
I eventually want to get some RTI A7's for surrounds and some A3's for the rears, but what I have makes me happy for now.

The Adcom is in the shop currently but normally runs the RTI-12's. The NR708 runs the rest.

I'm trying to decide on the best setup once I get the XPA-3. Should I bi-amp the RTI-12's? The things LOVE power so I'm tempted.

If I do, should I use the Adcom on the woofer section and use the XPA-3 to run the mids/tweets? Or should I use the Adcom or the XPA-3 to run the surrounds and use the receiver to power the mids/tweets and the XPA-3 or Adcom to run the woofers? I'm favoring the Adcom to power the woofers if I do bi-amp because it has a higher damping factor (700, yes, 700) than the XPA-3 (Approx 200) and (arguably) more headroom.

On the other hand, I'm not sure how worthwhile it is to send 200 wpc of power to the mids and tweets on the RTI-12's; most of the power gets sucked by the woofers. I'd think the 110WPC the Onkyo puts out would be sufficient, especially if it's only responsibility besides that was to power the rear surrounds.

Plus I'm not sure if there would be an issue with balancing the sound levels between the upper and lower sections?

The Sony towers really aren't power hungry at all, and I don't know if the crossover can handle 200+ watts. Once I get my hands on the RTI A7s I'd of course I'd end up using one of the amps to drive them too.

Either way I'm probably going to have to run a extension cord to another room, I don't know if the wiring in this room can handle two big amps plus the receiver and the TV.

Opinions or past experiences anyone?

Thanks!

M.B.
Teseract is offline  
Sponsored Links
Advertisement
 
post #2 of 13 Old 03-03-2012, 05:33 AM
Senior Member
 
chatanika's Avatar
 
Join Date: May 2008
Posts: 244
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I tried bi-amping and could not hear any improvement. most of the power goes to the bass so sending more power to the tweeter is a waste. If you feel that you need more power then just get a bigger amp for your mains , although that adcom should do the job. If your looking for a big performance gain I would throw as much money as you can afford on a subwoofer .
chatanika is offline  
post #3 of 13 Old 03-03-2012, 05:39 AM
AVS Special Member
 
Theresa's Avatar
 
Join Date: Nov 2010
Location: Minnesota
Posts: 2,430
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 50
Passive bi-amping does nothing but waste an expensive amp. I would use the XPA-3 for the L/C/R. It is a fine amp, I use it in my system too but am using active crossovers so the L/C/R midwoofers are powered by it.
Theresa is offline  
post #4 of 13 Old 03-03-2012, 04:24 PM - Thread Starter
Member
 
Teseract's Avatar
 
Join Date: Jan 2011
Posts: 125
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
So because the RTI12s have passive crossovers sending more power to them won't do much of anything?
Teseract is offline  
post #5 of 13 Old 03-03-2012, 06:03 PM
AVS Addicted Member
 
MichaelJHuman's Avatar
 
Join Date: Nov 2006
Location: Colorado Springs, CO
Posts: 18,652
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 127 Post(s)
Liked: 92
Quote:
Originally Posted by Teseract View Post

So because the RTI12s have passive crossovers sending more power to them won't do much of anything?

The low frequency side will always draw more power than the high side. Some say passive biamping can be useful still, though.

One thing to note, when passively bimamping from a amp with a shared power suoply, the supply itself may be the limiter.

If you are in a position to try it, I suggest trying it thus bypassing the endless threads discussing it's merits.

"But this one goes up to 11"
MichaelJHuman is offline  
post #6 of 13 Old 03-03-2012, 06:20 PM
AVS Special Member
 
Audiodork's Avatar
 
Join Date: Jul 2007
Location: Siesta Key, Florida
Posts: 2,441
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Liked: 29
I would leave the Adcom driving your Mains. The GFA-5500 uses a 1.5 kVA Toroidal Transformer as opposed to the 850VA used in the XPA-3. So in other words, the 5500 has almost twice as large of a transformer while driving one less channel. I would look for a matching GFA-5503 as opposed to adding an XPA-3. Also, the 5503 uses a 2.0 kVA Toroidal Transformer which is almost three times the size of the Emotiva.

Radio Shack SPL Meter Owner
Audiodork is offline  
post #7 of 13 Old 03-03-2012, 10:48 PM - Thread Starter
Member
 
Teseract's Avatar
 
Join Date: Jan 2011
Posts: 125
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I was considering this until I was sitting with the Adcom on reading a web page with nothing playing at all when the left channel of the GFA-5500 released it's magic smoke with a deafening WHUMP from an RTI12 and made my house reek for a couple hours... now I'm concerned about reliability and a 5 year warranty sounds nice to me. I'm still waiting for my Dad to finish fixing the Adcom.

I agree on keeping the Adcom on the RTI12's though, it does have more headroom. I really miss it. I tried to re-watch "The Tree Of Life" with no amp after watching it with the Adcom the first time... there's no comparison. The Onkyo just doesn't have the juice to handle 7 channels and the wattage sucking RTI12's and the CSI5.

Quote:
Originally Posted by Audiodork View Post

I would leave the Adcom driving your Mains. The GFA-5500 uses a 1.5 kVA Toroidal Transformer as opposed to the 850VA used in the XPA-3. So in other words, the 5500 has almost twice as large of a transformer while driving one less channel. I would look for a matching GFA-5503 as opposed to adding an XPA-3. Also, the 5503 uses a 2.0 kVA Toroidal Transformer which is almost three times the size of the Emotiva.

Teseract is offline  
post #8 of 13 Old 03-03-2012, 11:02 PM
AVS Addicted Member
 
MichaelJHuman's Avatar
 
Join Date: Nov 2006
Location: Colorado Springs, CO
Posts: 18,652
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 127 Post(s)
Liked: 92
Wow...Adcom's website shows new products? I thought they were practically dead.

"But this one goes up to 11"
MichaelJHuman is offline  
post #9 of 13 Old 03-03-2012, 11:07 PM - Thread Starter
Member
 
Teseract's Avatar
 
Join Date: Jan 2011
Posts: 125
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
There's nothing there I'd spend that much money on for sure.

Quote:
Originally Posted by MichaelJHuman View Post

Wow...Adcom's website shows new products? I thought they were practically dead.

Teseract is offline  
post #10 of 13 Old 03-04-2012, 06:01 AM
AVS Special Member
 
Audiodork's Avatar
 
Join Date: Jul 2007
Location: Siesta Key, Florida
Posts: 2,441
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Liked: 29
Now if only Indy Audio Labs started to release Aragon and Acurus Amplifiers... Hopefully they will soon.

Radio Shack SPL Meter Owner
Audiodork is offline  
post #11 of 13 Old 03-04-2012, 06:03 AM
AVS Special Member
 
Audiodork's Avatar
 
Join Date: Jul 2007
Location: Siesta Key, Florida
Posts: 2,441
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Liked: 29
Now if only Indy Audio Labs started to release Aragon and Acurus Amplifiers... Hopefully they will soon. Hold that, they are now selling new Amplifiers! Look kinda expensive so far, but they really do look nice.
Actually, they do have an Acurus 2002 that would be nice and far less expensive than the Palladium based Monoblock on the Aragon side. At least what is showing on the Website.

Radio Shack SPL Meter Owner
Audiodork is offline  
post #12 of 13 Old 04-18-2012, 10:39 PM - Thread Starter
Member
 
Teseract's Avatar
 
Join Date: Jan 2011
Posts: 125
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Well, Emotiva is running 10% off on a few items, so I finally pulled the trigger on an XPA-3, ~$630 shipped Fedex ground.

I'm looking forward to having some oomph in the front soundstage again, the Onkyo just can't handle 7 channels with the speakers I have properly. If I flip to stereo only it's not bad, but I was watching scenes from "The Tree Of Life" and it definitely didn't have the impact I had even with the Adcom just running the front left/right channels.

My Adcom GFA-5500 is still out of commission... my Dad is busy and isn't much working on it. I have a sneaking suspicion he's "burning it in" after repairing it and doesn't want to give it back yet...
Teseract is offline  
post #13 of 13 Old 04-19-2012, 12:23 AM
Newbie
 
ValerSterling's Avatar
 
Join Date: Apr 2012
Posts: 7
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Passive bi-amping does nothing but waste an expensive amp
ValerSterling is offline  
Reply Receivers, Amps, and Processors

Tags
Onkyo Tx Nr708
Gear in this thread

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