Emotiva XPA 2 vs Onkyo TX-SR706 for a 2.1 system!?!?!?!

[Rich_Guy]

Max rated power handling is 150W continuous, 600 watt peak.

According to Crown Audio you should have an amp power about 1.6 to 2.5 times the continuous speaker wattage rating.

http://www.crownaudio.com/amp_htm/amp_info/how_much_power.htm#'> http://www.crownaudio.com/amp_htm/amp_info/how_much_power.htm#

[StephenM]

Which brings us back to those woofers.. i am still a bit suspicious about that 4 ohm load; you revealed Here that Klipsch techs had told you about RF-5s dipping to 4 ohm at ~200Hz.. then what about 50Hz? Depending on slope, RF-5 also would attempt to produce sound at even lower frequencies..

This was when I was asking for impedance & phase curves on the RF-5. When I e-mailed Klipsch techncal support, they said the impedance minimum is 4 ohms at ~200Hz. If that information is factual, impedance is higher at 50Hz, although it is likely still fairly low. As far as the slopes go with the RF-5s crossed at 50Hz, the RF-5s will be 3dB down at 50Hz, and will roll off at 12dB/octave. Of course, below the tuning frequency of the speakers, all the output is basically going to be distortion anyway, regardless of how clean the power is.

I am not saying your calculations are incorrect; however, they would mean that XPA-2 and 706 perform exactly the same at different (reasonable) listening levels

Not necessarily; there are other measurements that I have not presented or have access to that may impact listening tests. However, one expects based on the measurements that they will perform fairly closely at lower volumes so long as the speakers are fairly sensitive, and don't dip too low in impedance.

emotiva does not seem to be the kind of company that would base their sales on psychoaccoustic effect

They certainly don't; there are obvious tangible benefits to the XPA-2 over the Onkyo, namely considerably more clean power on tap, not to mention the ability to add on to the Onkyo or any other receiver with pre-outs to supplement said receiver.

If you are looking for encouragement to continue using receiver instead of separates, you are likely in a wrong forum hehe.

Not to worry, I'm not looking for encouragement, just presenting measurements I found most interesting.

[StephenM]

According to Crown Audio you should have an amp power about 1.6 to 2.5 times the continuous speaker wattage rating.

FWIW, THX certifies that the Onkyo will effectively deliver a 50V peak into the front channels. That equates to over 300 watts at 8 ohms and over 600 watts at 4 ohms. I'd wager that's adequate for listening with peaks of 90dB at the listening position in my room, with my speakers.

[StephenM]

Believe whatever you wish but don't always believe everything you read, it is often wrong, especially when it come to charts, graphs and other specifications.

Whatever you need to tell yourself. I'll choose to believe the magazine that is accountable for the measurements it publishes, both to its readership and to the manufacturers, especially when the measurements another magazine (S&V) takes, while not identical in method, correlate very well with the measurements I posted from Secrets.

[willland]

This thread is making me dizzy.[8-)]

I know Emotiva amps(XPA-2) are the other subject in this comparison, I just wanted to inject another brand into the mix.

With that said, my RF-63's driven by my Onkyo TX-SR705(100watts/channel) sounded very good. Added B&K Reference 4430(200watts/channel) and those same RF-63's were transformed. Warmth/musicality, detail, punch, headroom were all improved and very noticeable after the change both in low volume listening and with cranking it up.

Now my Onkyo TX-SR705 has been moved to bedroom 5.1 duty and is powering RVX-42's and I think alone(no outboard amp) is better suited for an LCR(satellite) system. I really doubt adding the B&K to that system will yield real discernable improvements like is has with my RF-63 system.

Remember, measurements are just that, only measurements. As most have exclaimed in the many replies, the sound to one's own ears is more important in the end.

Bill

[StephenM]

Remember, measurements are just that, only measurements. As most have exclaimed in the many replies, the sound to one's own ears is more important in the end.

Surely: some people love the Bose sound or amplifiers that yield very high levels of second order distortion, regardless of how objectively poor their measurements may be. Some people love the "sound" of high end cables regardless of the fact that at best, they are glorified tone controls. To each their own. I sleep just fine at night with my system, and am comfortable with the knowledge that seems to make some forum members here squirm and claim that the magazines measurements must be mistaken.

[StephenM]

Since people seem to have so much trouble with my hypothetical information on the RF-5, lets switch to something with comprehensive measurements: ladies and gentlemen, I give you the JBL L890.

http://www.soundstagemagazine.com/measurements/jbl_l890/

Per the graph, it is between 87 and 88dB sensitive at 50Hz with a 2.83V input, and ~92dB sensitive at 100Hz. These are anechoic mesurements, so bass response in room will naturally be better, but lets be uber-conservative, just to drive the point home. Moreover, its impedance does not dip below 4 ohms, making it a reasonably easy load to drive.

Even in an anechoic chamber, with 20V output from the Onkyo, at 9 feet (my listening distance), a single speaker will output 95dB at 50Hz and 100dB at 100Hz, while the Onkyo will not exceed 0.03% THD+N.

Of course for those of you that believe magazine measurements are untrustworthy, this proves nothing. For those that have faith that the magazines aren't liars or incompetent, more food for thought.

[Rich_Guy]

Remember, measurements are just that, only measurements. As most have exclaimed in the many replies, the sound to one's own ears is more important in the end.

Surely: some people love the Bose sound or amplifiers that yield very high levels of second order distortion, regardless of how objectively poor their measurements may be. Some people love the "sound" of high end cables regardless of the fact that at best, they are glorified tone controls. To each their own. I sleep just fine at night with my system, and am comfortable with the knowledge that seems to make some forum members here squirm and claim that the magazines measurements must be mistaken.

I trust my own ears before I trust any magazine, what my own ears have experienced is a dramitic difference between the two. Sure there are many people who are not into this hobby and an mp3 playing on an iphone may sound as good as anything to them. I appreciate good sound, I know there is a difference, I have pretty picky ears and a lot of experience distinguishing what is really good.

Specifications & measurements will only tell you so much and that is when they are correct often they are wrong, errored or worse just made up to represent the writers view or even worse yet what he's paid to advertise.

Regardless if measurments are correct or not music is to be listened to not measured. Measurements can measure things the human ear cannot hear and I am sure the human ear hears things we are not capable of measuring.

I am not saying don't use specifications, measurements, etc, when making your decisions just do not make them everything.

I have owned three high end Onkyo receivers, one was top of their line, two Sony, one a Sony ES, without a doubt in my mind my XPA amps out perform the amps in them all.

[willland]

I sleep just fine at night with my system, and am comfortable with the knowledge that seems to make some forum members here squirm and claim that the magazines measurements must be mistaken.

I am not one that thinks the data is incorrect, I just think that the data is not the the most important aspect in the whole scope of things.

Take a Formula One car and a Top Fuel dragster and let them run the quarter mile. Of course the dragster may clock a time of 4.5 seconds at 320mph and the F1 may "only" clock a time of 8.5 seconds at 180mph. Take the same dragster and F1 car and run them both at Monaco and see if the dragster runs away with it. I think not. The F1 car with about 12%(1000hp) of the dragsters power(8000hp) may post a 1:15 time at an avg. speed of 100mph while the dragster would not make it past turn one.

So, which is the "better" racecar?

I do see what your point is. Given the "racetrack" in which you choose to race on, the car(amp) with the most HP(watts) does not mean it will perform better.

Bill

[StephenM]

I do see what your point is. Given the "racetrack" in which you choose to race on, the car(amp) with the most HP(watts) does not mean it will perform better.

Bingo. Nothing more, nothing less.

[StephenM]

I trust my own ears before I trust any magazine, what my own ears have experienced is a dramitic difference between the two.

More power to you. You have every right to believe what you want to believe.

I am sure the human ear hears things we are not capable of measuring.

We aren't trying to measure sound; we're measuring electrical output, something we have a greater understanding of.

I am not saying don't use specifications, measurements, etc, when making your decisions just do not make them everything.

I understand this. I don't expect everyone to drop their Emotivas and rush out to buy Onkyo. Just as in my OP: food for thought. Nothing more.

[Rich_Guy]

Enjoy looking at the graphs with measurements of your system since that seems to mean the most importance to you, I hope they are correct.

I will enjoy listening to and using mine, charts and graphs are a nice tool, but I bought my system to sound good and it really does.

Time to go enjoy the holiday weekend, happy Labor Day all.

[StephenM]

Enjoy the long weekend Rich. I hope there are no hard feelings from this lively discussion.

[cornfedksboy]

Enjoy the long weekend Rich. I hope there are no hard feelings from this lively discussion.

Stephen, I have no hard feelings and I hope you feel likewise towards me. Please forgive my "badgering" and rather borish "attacks" but I felt that your argument was strong enough that it warranted a serious critical rebuttal. I have very much enjoyed this discussion and I have learned alot through your posts and some independent reading in relation to them. I welcome any further info.

I haven't fully hashed out all of my thoughts on this, but I am quite sure that you have presented enough evidence so as not to be a rash hypothesis.

7 pages into the discussion, how does your system sound?

[StephenM]

Stephen, I have no hard feelings and I hope you feel likewise towards me

No ill will at all cornfed. Wouldn't be much of a discussion or nearly as informative a thread without some point and counterpoint.

I welcome any further info.

If you want some light reading, you can check out Roger Russell's thoughts. http://www.roger-russell.com/truth/truth.htm Interesting reading to be sure, even if you don't agree with everything he says. I do enjoy the audio brick test.

7 pages into the discussion, how does your system sound?

What can I say, it has provided me with some fantastic musical reproduction and home theater experiences. Of course, there's always room for improvement. The next project for me: the listening room, both because it is an acoustical mess, and because it's stuck in the 1970s (with the finest wood paneling and poop brown tile) , whereas the rest of the house has been remodeled.

[StephenM]

Just for conversational purposes, I'll also throw in my subjective take on this topic. This little anecdote is about my bedroom speakers: while massively insensitive (~82dB with a 2.83V input), they're also an easy load for an amplifier, never dipping below 8 ohms, and staying fairly flat on the impedance curve. I've driven these speakers with 3 items so far. Objectively, the best was an HK stereo receiver rated for 80 watts per channel. Frankly, this combination was magical, and reproduced some of the best music I've ever heard, and I've heard more than a few systems well beyond what my pocket book can afford. Eventually I decided I would turn this little setup into my home theater system; I (stupidly) gave the stereo receiver to a relative, and got a HK AVR to drive them. The magic was still there, and with the addition of a subwoofer, had gone up a notch. When I got my RF-5s, my other speakers went back to the bedroom. I had nothing to power them with, so in the interim of considering what to drive the RF-5s with, I obtained a cheapo Insignia stereo receiver. Guess what? The magic was still there. Even with a sub-$100 receiver driving them, these things imaged like magic, had deep tuneful bass as low as the RF-5s could muster (the upside of 82dB sensitivity), had plenty of punch, and frankly were a blast to listen to. When the HK AVR made it to the bedroom, did I notice a difference? Just that I could turn it up louder. That experience was enough for me to form my opinion: if an amplifier/receiver is competently designed, and has enough clean juice to drive your speakers to the level you desire, things will probably turn out well. After that, I think its wiser to spend money on better speakers, room treatments, and more CDs. But again, just my subjective opinion.

[W27]

I'm very interested in the attenuators you're talking about, Rich. I have a very similar setup. Integra DHC 9.9 with RF-7's all around. With the Audyssey it sets all of my speaker levels at nearly the max negative level as well. It really puts a damper on everything. I feel that it's taking away all of the power that I paid for. Sometimes I like to set the dynamic eq to heavy to keep the effects from getting too out of hand, but when I do that I can turn the volume up 100% and feel like it's not enough on certain movies. I recently raised all of my levels with my spl meter. The test tone becomes nearly unbearable in the upper range. Now I have all the power I could ever want, but it seems to have thrown the other settings out of whack. Now if the regular dynamic eq is on there is so much bass it shakes all of my windows even at low levels with no subwoofer. I realize that this isn't the thread to do this, but I found your attenuator reply above. If you'd rather send me a pm or I could start my own thread. I'd really appreciate any advice.

[StephenM]

Time to beat this old dead horse again:

Just a little data to add:

Now like most Klipschites, my RF-5s are rated to
be fairly sensitive. However, being the conservative type, I'll say that
they are 95dB sensitive with a 2.83 volt input

http://www.hometheater.com/content/klipsch-reference-rf-83-speaker-system-ht-labs-measures

Not RF-5s, but it does show just how darned sensitive Klipsch RF speakers
are, particularly at lower frequencies. I'm duly impressed that an RF-83 can
pull 95dB with 2.83V at 50Hz under quasi-anechoic conditions. Add a few dB for room
gain, and you've got its specified sensitivity.

http://www.hometheater.com/content/klipsch-reference-rb-75-ht-labs-measures

The RB-75 system measurements are very interesting to me, not for the RB-75, but for the RC-7 which shares a few parts with the RF-5s. Of course its low end tapers off quite a bit in comparison with the RF-83s for a few reasons, not the least of which are its significantly smaller cabinet volume and design expectations. Of course, even a wee RB-75 is able to pull 90dB sensitivity at 50Hz.

Gives me a little more confidence in my original estimates on power requirements.

[cornfedksboy]

I must give you due respect for your ability to find and present data!

[StephenM]

I must give you due respect for your ability to find and present data!

Thanks cornfed.

I've actually posed the question directly to Emotiva, ie is there likely to be an audible difference between the XPA-2 and the Onkyo TX-SR706 under the original conditions along with the graphs, and if there was a difference, why that would be the case. I received a response on Friday from their sales team saying they would forwarding the question to the technical side, but I haven't seen a response yet. I'm curious as to what they have to say.