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Post by audioalan on Jul 13, 2010 16:47:54 GMT -5
Hi everyone,
I've been looking at Emotiva's amps and I'm wondering what would be better to help my current system have more power. Here's my current setup:
Pioneer Elite SC-27 (7.1, 140 Watts/channel) running...
Fronts - Polk SRS SDA 2.3's - 8 ohms, 50-750 watts/channel
Side Surrounds - DCM Time Windows - 5 Ohms minimum/6-8 Ohms nominal, 200 watts max.
Rear surrounds - Polk RTA-11t's - 6 Ohms, 10 - 250 watts
Center - Yamaha (can't remember the model), 140 watts. 8 ohms, I think.
Subwoofer - Two Polk PSW-505s.
When I had all of my speakers set to Large, my SC-27 went into protect mode during the Depth Charge scene on U-571. After I set the side and rear surrounds to small, I could play that scene without it shutting off. To me that says the SC-27 isn't powerful enough for all my speakers to be set to Large, at that loud of a level, with that dynamic of a scene (if you know the movie, you probably know what I mean)... and that was before I replaced my old 80 watt/channel mains with Polk 2.3's (which are supposed to be really power hungry, taking up to 750 watts per channel). So, I'm thinking I might want to add an external amp to help my SC-27 out a bit.
To make a long story short, would I be better off buying a XPA-2, just to power the Polk 2.3's, or should I go with a XPA-5 to power the 2.3's as well as the rear surround Polk RTA 11t's (and possibly the Center)?
Will only powering the front with an Emotiva amp, and the Center from the SC-27, make a difference in sonic quality? It is suggested that all 3 of the front speakers run off the same amp?
Will leaving one or more channels unused on the XPA-5 allow those channels to have more power, or are they completely separate and unused channels won't affect the other channels in use?
Thanks,
Alan
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Post by roadrunner on Jul 13, 2010 22:20:11 GMT -5
Alan,
Yes, you should drive at least the Fronts and Center with an Emotiva amp. I believe you would be best served by going with the XPA-5. You are correct in thinking you can use the XPA-5 without driving all five channels and that those channels being used will have access to even greater output. The XPA series amps use a "pool" to draw from and any attacked speakers have access to the full output of the pool.
The Emotiva power amps will give new life to your speakers. They will amaze you by how much the sound quality of your system improves. There are a lot of options you could pick from in the Emotiva line for driving your system. An XPA-2 plus and XPA-5; XPA-1 or UPA-1 Monoblocks for FR, FL and Center plus XPA-5 for the remainder. If you have a tight budget, you might look at using the Pioneer receiver to drive your surrounds, but after hearing what a separate power amp can do for the sound of your speakers you may not like listening to the speakers driven by the receiver. Good power amps can spoil you for listening to anything less. ;D Good luck with your upgrade.
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Post by puppetz on Jul 13, 2010 22:24:36 GMT -5
Do you use your system exclusively for movies? Do you always have all your speakers set to "large" even though you're running dual subs? If the answer to both questions is "yes", I'd definitely recommend the XPA-5.
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Post by broncsrule21 on Jul 13, 2010 23:35:23 GMT -5
just curious....why, with two subs, are you running all your speakers "large"? Regardless, with the XPA-5 in the mix you won't have the protect mode problem.
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Post by audioalan on Jul 14, 2010 1:36:05 GMT -5
Thanks for the responses, guys. To answer the questions...
I watch movies, play games on a PS3, and listen to music and SACDs. So basically I use my receiver for everything.
Regarding why I set the surrounds to Large - If a speaker is good enough to put out the full range of sound, why not use it? Perhaps this is flawed logic, but it seems to me that allowing all of the speakers to play the lower frequencies would help the response be smoothed out over the entire room, for all seating positions. (Just like the reason for running multiple subs). Wouldn't having a specific frequency come from several directions (instead of just from the subs) help eliminate the chance that someone is sitting in a NULL? I'm also a little leary about having the receiver redirect sub frequencies from multiple speakers to the subs. Didn't the audio engineers mix the audio on movies to be the way they wanted it? If so, why redirect content from one speaker to another? It seems like you are contradicting the design of the movie. Finally, if strong bass is coming from all speakers (and they are all set to Small), are you more likely to clip the subs because the summed signal is very hot? Setting the speakers to Large alleviates these questions. Maybe someone has some good answers to these questions...
Yeah, I'm leaning more and more towards the XPA-5. I hear the Polk 2.3s really come alive with more power, and I wouldn't say 140 watts fits the "more power" bill (considering the speakers can handle 750 watts).
Sounds like I don't have much time to decide. I think the sale ends in another day or two...
Alan
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Post by oppman99 on Jul 14, 2010 10:16:20 GMT -5
In terms of whether or not to run speakers full range or small, I think it is in many cases a matter of personal preference. If you like the sound you're getting running your speakers full range, I say go for it. I run Paradigm Signature S8's as small with a sub crossed over at 50 Hz (music only setup). My thinking is that the sub will do a better job of handling the low frequencies and take some of the load off the speaker. As for having low frequencies coming from multiple speakers and smoothing nulls, it may be true, but it may also cause peaks in places resulting in more bass than was intended.
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Post by audioalan on Jul 14, 2010 10:40:17 GMT -5
Oppman99 - Yeah, good point about the possibility of it creating peaks as well. I think a little extra bass occassionally in a movie is better than it sounding wimpy though. (Once again, that's personal preference). Maybe I'll try a lower crossover point (instead of 80 Hz) and see if I like it that way.
Either way, more power should make my setup sound better. I was just wondering if the XPA-2 or XPA-5 would fit my situation better. Sounds like the consensus is the XPA-5.
Dang, looks like the XPA-5 is now Sold Out as well. :-(
Alan
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Post by oppman99 on Jul 14, 2010 14:18:00 GMT -5
I believe you can still reserve one at the sale price until the 15th if you have decided on the XPA-5. At least that's what the e-mail said this morning.
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Post by audioalan on Jul 14, 2010 14:29:54 GMT -5
Yeah, I might just do that. But I'm still debating. I tend to analyze these things every which way from Sunday... much to my own torture. Alan
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Post by beekermartin on Jul 14, 2010 15:21:03 GMT -5
I also agree that running your speakers as large with two subs probably isn't the best sounding setup.
My main speakers and center can be ran as large but I don't. I cross my mains at 50 and my center at 80. The reason is that you don't need to have bass coming from those speakers if your sub is more capable of it. Subs are designed just for low hz bass. Main speakers, even those "capable" of low hz aren't designed for very low hz output. Do you really think your main speakers should be trying to reproduce a 20hz signal at loud volumes?
For music only setting them as large is probably ok. Most music doesn't hit the very low hz as movies do. The only instrument that really hits the lows is a pipe organ. Movies on the other hand hit the lows often and hard. That is when letting the sub handle the load is usually the best idea. Of course YMMV.
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Post by UT-Driven on Jul 14, 2010 15:27:37 GMT -5
Isn't the XPA-2 supposed to better for music than the XPA-5 since it is overbuilt (more output devices, etc...) when compared to it? Since you mentioned SACD and music in your options and have a speaker such as the SDAs, I would be leaning in that direction myself.
Doug
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Post by audioalan on Jul 14, 2010 16:14:11 GMT -5
Beekermartin - I'll try playing around with the x-over. I thought 80 Hz sounded a little weak, so I switched the mains back to Large. Maybe 50 Hz will be better... (after I had that protection mode incident with the U-571 scene, only my mains are still set to Large).
Doug - Yeah, the XPA-2 sounds nice, but then the Center would have to run off the Pioneer still. Lots of people are saying the front sound stage should all be run off the same amp. Not sure if I could tell the difference or not, but I could try some experimenting. If no difference is noticed, I could only run the Front L/R off the XPA-5, which would boost the output considerably - even higher than the XPA-2. Correct? Any danger in running the XPA-5 as a 2-channel amp - just to boost it's power output?
Alan
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Post by beekermartin on Jul 14, 2010 16:32:09 GMT -5
Beekermartin - I'll try playing around with the x-over. I thought 80 Hz sounded a little weak, so I switched the mains back to Large. Maybe 50 Hz will be better... (after I had that protection mode incident with the U-571 scene, only my mains are still set to Large). Doug - Yeah, the XPA-2 sounds nice, but then the Center would have to run off the Pioneer still. Lots of people are saying the front sound stage should all be run off the same amp. Not sure if I could tell the difference or not, but I could try some experimenting. If no difference is noticed, I could only run the Front L/R off the XPA-5, which would boost the output considerably - even higher than the XPA-2. Correct? Alan Try different crossovers and see if any of them sound "full" to you. It is the very low hz @18-30 that really are best reproduced by a sub. My Onkyo allows me to set the cross over as low 40hz. Try to set them as low as your receiver lets you before selecting full range. Also, remeber to check your speaker levels after adjusting the cross overs using a SPL meter. If you aren't happy with the bass try to raise the sub level slightly to see if that helps. Of course if your happy with the sound quality using full range than run with it. I would think that on very demanding low hz scenes you are probably getting some distortion but bass distortion is tough to notice. It usually sounds muddy instead of clean/tight. Some people like the sound of muddy bass. Some like accurate bass. It is up to you what sounds good. Overdriving a driver in the low hz is very noticeable. I've heard subs being over driving in certain scenes. You will be able to hear when the driver is bottoming out! If none of your speakers do that then you might be ok running them as large. Once you have more power though you may find that happening. BTW, if you mainly watch movies than go with the XPA-5 first. You can always add an XPA-2 down the road if you decide to expand to a 7.1 setup or add a second zone. The XPA-5 will be much more powerful than your receiver's amps. I don't know what your receiver is rated at with 5 channels driving but I imagine it isn't close to the rated 140 watts. Most receivers drop down to close to half of their rated power with 5 channels driving. The XPA-5 is rated at 200 watts with all channels driving. I believe most tests showed it was even more powerful than that.
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Post by audioalan on Jul 14, 2010 17:03:22 GMT -5
Thanks for another response, beekermartin. So far I haven't had problems with overdriving my speakers, except for once - and it was the sub. Part of that may have been related to too much boosting on my parametric EQ (for a dip where the frequency response was weak, due to less than optimal room acoustics - which I'm working on). I have since tamed down my EQing, and bought a second sub to help out (and to smooth out the response). Now I can run the two subs at under half volume each vs. one at 3/4's before. No more problems, even at very loud levels.
I'll try lowering the x-over as you suggest.
Back to the XPA-5 - What do you think about just running the XPA-5 as a 2 channel amp? Sounds like it should be even more powerful than the XPA-2 - since it's total power is 1000 watts (200x5) vs. 600 watts (300x2)...
Thanks,
Alan
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Post by Topend on Jul 14, 2010 17:05:13 GMT -5
Having been down the same road, my recommendation is get the XPA-5 first and consider adding the XPA-2 later.
Cheers, Dave.
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Post by rygher3 on Jul 14, 2010 17:17:54 GMT -5
The Pio Elites have pretty good power actually. Your surrounds and center should have plenty of power from your receiver. The way for you to really make an improvement would be giving the 2.3s even more power. I think the XPA-2 would be a great fit for you.
However, running the 2.3s in full range definitely would be a huge power hog, so maybe check and see how it runs with a crossover of somewhere around 50hz(i'm not sure where the SC-27 allows you to cross).
Here are the actual power measurements of the SC-27 (From hometheatermag.com): Five channels driven continuously into 8-ohm loads: 0.1% distortion at 111.3 watts 1% distortion at 131.4 watts
Seven channels driven continuously into 8-ohm loads: 0.1% distortion at 107.4 watts 1% distortion at 124.2 watts
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Post by audioalan on Jul 14, 2010 17:50:25 GMT -5
rygher3 - Thanks for the stats on the Pioneer. Sounds like the Pioneer isn't as beefy as they claim. Probably don't want to drive it much past 115 watts with 7 channels driven. That makes the XPA lineup even more compelling to help out my SC-27...
What about the difference between running the XPA-5 in 2-channel, vs. XPA-2?
XPA-5 - 1000 watts (200x5)/2 = 500 wpc - when only using 2 of the channels XPA-2 - 600 watts (300x2)/2 = 300 wpc (obviously)
Seems like that would give me more flexibility to run 5 channels, or unhook 3 of the channels and only run the mains with 500 watts each in 2-channel mode. Am I missing something here?
Thanks,
Alan
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Post by UT-Driven on Jul 14, 2010 18:16:20 GMT -5
rygher3 - Thanks for the stats on the Pioneer. Sounds like the Pioneer isn't as beefy as they claim. Probably don't want to drive it much past 115 watts with 7 channels driven. That makes the XPA lineup even more compelling to help out my SC-27... What about the difference between running the XPA-5 in 2-channel, vs. XPA-2? XPA-5 - 1000 watts (200x5)/2 = 500 wpc - when only using 2 of the channels XPA-2 - 600 watts (300x2)/2 = 300 wpc (obviously) Seems like that would give me more flexibility to run 5 channels, or unhook 3 of the channels and only run the mains with 500 watts each in 2-channel mode. Am I missing something here? Thanks, Alan I don't recall what the wattage in 2 channel mode is, but it is not 500 wpc for the XPA-5 by my recollection. I want to say it was around 300 wpc into 8 ohms if you only use 2 channels. This information used to be on the page, but it is no longer there. I looked for a XPA-5 review and could not find one that had the measurements. Getting an XPA-3 or XPA-5 now and getting a XPA-2 down the road is not a bad plan at all. Doug
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Post by audioalan on Jul 14, 2010 18:31:24 GMT -5
Doug - Yeah, I figured the XPA-5 putting out 500 wpc seemed too good to be true. But even at 300 wpc, it's sounds like it would be almost equivalent to the XPA-2 (... but I'd assume the XPA-2 would have to be cleaner, or something, from looking at the specs and since it has 3 less channels).
Alan
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Post by johndavidson on Jul 14, 2010 20:21:38 GMT -5
The voltage rails on the power supply would limit the power output in 2 channel mode to much less than 500 watts /ch. The biggest gian would be in 2 channel mode driving 4 ohm speakers but I would suspect at most 400 watts / ch with only 2 channels driven.
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