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

[StephenM]

As far as I'm concerned, the differences, and where I'd put my time and energy are in the room, source material, and speakers. YMMV I suppose. Whatever let's you sleep at night happy with your system. As for me, I'm rather happy with my little Onkyo; it gets the job done quite nicely.

[psg]

[Y]

I am one the same page as you.

[Rich_Guy]

Well I have always loved my RF-5's but using them with the XPA-2 over the Onkyo's power brings them to a whole new level, I have never been more satisfied with them. The XPA-2 was an extremely nice upgrade and the RF-5's absolutely loved it.

[Danzo]

It's a no brainer. XPA-2 is better than midrange receivers at all volume levels. Even if you like your music relatively quiet, you will notice improvement in bass and clarity. However, XPA amps exhibit higher noise levels with sensitive speakers than i would like, which made me move on to another amp.

[StephenM]

Well I have always loved my RF-5's but using them with the XPA-2 over the Onkyo's power brings them to a whole new level, I have never been more satisfied with them. The XPA-2 was an extremely nice upgrade and the RF-5's absolutely loved it.

No doubt that it is a serious upgrade for most people. If I had a bigger room and sat further away from the speakers, or if I listened a bit louder or to more dynamic music, or if I were using more than just 2 channels on the Onkyo, etc etc, it would be a significant upgrade. However, it's hard to argue that within the specific confines of my evaluation, with the measurements speaking for themselves, the Onkyo can hold its own. Not to discount your experience, but the fact is you're more prone to bias then testing equipment, unintentional as it may be. The XPA does something for you, and that's fine. But the fact remains, the Onkyo is as clean and capable at the specific levels I'm discussing, and cold hard data bears that out.

[StephenM]

XPA-2 is better than midrange receivers at all volume levels. Even if you like your music relatively quiet, you will notice improvement in bass and clarity.

Evidence? Hard data indicates otherwise. And no, an informal sighted comparison isn't evidence.

[Rich_Guy]

My room is fairly small 15 ft x 14 ft seated listening distance is aprox 7-8 ft and my listening levels volume levels did not change although the improvement was as evident at low volumes as well as higher volumes.

Differences in 2 channel music were huge. In my 20 plus years of enjoying this hobby and having a nice system and with making many system changes and upgrades during this time, I would rank the change from the Onkyo's amp to the XPA-2 as one of the better changes I have made.

For instance detail and clarity, some songs which certain lyrics could not be understood became as clear as day, while in some other songs differences between the main lead and background singers voices became evident, where it may have sounded as only one voice before. These are the types of changes noticeable to music I was very used to listening to on my system.

[StephenM]

So here's a question or two for you: how did you come to your conclusions? Did you volume match within 0.1dB during your comparison using a voltmeter? Did you do any blind testing?

[Danzo]

I only tried 506 and 3008 Onkyos in my system and stopped bothering with it.

Evidence to me is my ears and i did not need to sit with spl meter and draw graphs to conclude that, it was bleeding obvious.

Now, my ears and room effects are probably different from yours and everybody elses, but

if you think that all equipment that measures perfect, will sound perfect, you're in for a nasty surprise.

[StephenM]

Evidence to me is my ears and i did not need to sit with spl meter and draw graphs to conclude that, it was bleeding obvious.

It's curious how things that are bleeding obvious become less so when the levels are matched within 0.1dB, and the identity of the amplifiers is hidden.

In any case, if you're happy with your evidence, great. In the end, you don't need to prove anything to me or anyone else to enjoy your system. However, when you start making statements that one amplifier is (objectively) better than the other, you'll need something better than informal sighted listening tests as evidence.

[StephenM]

Just a little tidbit courtesy of Stereophile for those who their ears are all the evidence they need. Emphasis is mine.

http://www.stereophile.com/content/mark-levinson-no38s-preamplifier-level-matching

It's essential in listening comparisons to match levels to at least within 0.1dB. A component that's, say, 0.2dB louder than another won't be heard as being louder. Instead, listeners will comment on greater apparent detail or better dynamics.

Stereophile's recommended means of matching levels is to choose a volume-control setting for the comparison, then play a reference tone from a CD—I included a 1kHz tone at –20dBFS on all three Stereophile Test CDs for this purpose. An AC voltmeter is then used to measure the voltage present at the power amplifier's speaker output terminals: as long as the levels for the two upstream components are within 1%, the sound-pressure levels will be matched to within 0.1dB

[Rich_Guy]

I have an SPL meter and my listening levels have not changed also as noted the change effected listening at all levels low as well as higher volumes, this is not a matter of the amp making things louder so things appear to sound different.

No blind testing needed the differences are very real and apparent. However I believe blind testing everything can also provide false results, there are times when even very different speakers cannot pass blind testing accurately.

I think you are going about deciding on making an upgrade the wrong way, what you really need to do is listen for yourself and compare what you like. If you go solely by measurements and statistics you won't notice nearly as much
difference in different brands or components as you will by listening to
them. Listening to music is not something statistical and I doubt that all improvements or changes are always measurable.

Another example of a difference I noticed when changing to external amp power from using the Onkyo's internal amps, bass was improved considerably. On my Onkyo receiver using Pure listening mode which uses no subwoofer bass increased noticeably almost as though it was using the sub (except for real low lows) the power and punch of bass was much better, this would be attributed to headroom. Before adding an amp I never liked listening to Pure listening mode bass was just too weak but after adding an amp I found I did enjoy this mode and began switching between it and Stereo mode for 2 channel music listening.

[StephenM]

I have an SPL meter and my listening levels have not changed

Most SPL meters are not accurate enough to provide proper level matching. See my quote from Stereophile. Even a 0.2dB difference is enough for your results to be skewed, and would in fact explain improvements in detail when you did your comparisons.

No blind testing needed the differences are very real and apparent.

Unconscious biases make things appear very real and apparent. IOW, people hear what they want to hear. When you look at an 80 pound power amp, you expect it will beat the snot out of a 25 pound receiver in every conceivable way. It's a natural thing to expect. That doesn't make it objective fact.

However I believe blind testing everything can also provide false results, there are times when even very different speakers cannot pass blind testing accurately.

Testing methodologies that may lead to error aside, what special insights do you suppose are lost by you not knowing the identity of properly level matched amplifiers playing for comparison purposes until the test was over?

Listening to music is not something statistical and I doubt that all improvements or changes are always measurable.

Statistical? No. But there is considerable science behind the technology that lets you listen to a CD or LP in the comfort of your home, and that science is reasonably well understood. Suffice it to say, manufacturers aren't sprinkling magical pixie dust on their products in hopes of improved sound.

this would be attributed to headroom

Do you realize that the Onkyo is certified by THX to cleanly swing a 50V peak? That equates to 625 watts at 4 ohms, and 312.5 watts at 8 ohms. If we're talking about levels where the receiver is putting out 3-6 watts into 2 channels, I have a hard time believing headroom is a problem.

[StephenM]

what you really need to do is listen for yourself and compare what you like.

One other question for you: what place, if any, does objectivity have in this hobby for you?

[Danzo]

Fair enough. In my case - i am saying XPA is better than Onk but i have absolutely no proof whatsoever.

Let's see if guys armed with proper testing equipment and enough care to use it would chip in.

[Rich_Guy]

Well, since you believe that most upgrades are just psychological just use whatever system you have now or base all your upgrades on whatever hard evidence you need.

I have been using and upgrading my system since the late 1980's choosing my system changes very carefully. Sometimes I have absolutely enjoyed the changes I have made sometimes not so much. I consider my system in it's current form a huge difference from what I started from. I also consider switching from receiver power to separate amps one of the significant changes I have made and one which has brought a huge improvement to the sound quality, a huge smile to my face and a lot more enjoyment to using my system.

I am a little curious if you go to a restaurant do you require to see the recipe or maybe chemical analysis tests to be sure you will enjoy your meal or to compare it to another restaurant's recipe or can you decide on what you feel tastes best?

I use many things in deciding on my system changes when I make upgrades to the sound of my system and try to make my choices carefully but in the end it is what my ears hear which determines which sound I like best.

If you really want to find out, Emotiva has a 30 day return policy try the XPA-2 on your own system for yourself.

[StephenM]

Fair enough. In my case - i am saying XPA is better than Onk but i have absolutely no proof whatsoever.

Let's see if guys armed with proper testing equipment and enough care to use it would chip in.

The XPA absolutely is better than the Onk. I don't question that. What I'm saying is that in a very limited circumstance, measurements are indicating that the XPA isn't better.

Granted, they aren't all encompassing measurements: I haven't shown things like damping factor, crosstalk, etc as they weren't included in either review. At the same time, we aren't discussing entry level Insignias here. Both a $900 receiver and a $800 stereo amplifier should have these things sorted out. Given that the receiver is the item that is under the most scrutiny, there is some additional assurance that these items are in order as they are part of the THX certification for receivers, along with a multitude of other aspects of performance.

[StephenM]

Well, since you believe that most upgrades are just psychological

Certainly I wouldn't qualify most upgrades as psychological. There are very obvious measurable differences between a pair of Bose cubes with a bass module and a pair of RF-5s as an example. These measurable differences readily translate into audible differences, and one could say that the RF-5s are objectively superior. However, some people may still prefer the Bose system because perhaps the sound does something for them, or because Bose marketing has done it's job.

I am a little curious if you go to a restaurant do you require to see the recipe or maybe chemical analysis tests to be sure you will enjoy your meal or to compare it to another restaurant's recipe or can you decide on what you feel tastes best?

Probably a bad example to try to illustrate your point; aside from the fact that taste is purely subjective (I despise curry for example, but many Indians love it), I am very stringent about what I eat; like everyone I like good quality ingredients (and I personally shun places like McDonalds), but I'm also very conscious about what I eat as it relates to my health. As a result, I mostly cook for myself from scratch, and what I don't make myself, I do look at ingredients and nutritional value.

Conversely, suppose you were enjoying a meal at a fine restaurant, and unbeknownst to you, the chef substituted dog meat for ribeye. If you don't notice the difference, does it matter? Suppose the chef doesn't like to wash his hands after he uses the bathroom. If you don't get sick, does it matter?

[cornfedksboy]

This is, at it's core, another argument as to the merit of double-blind testing versus emotional appeal to music. Even in a double-blind study, music that "appeals" to the listener will result in a higher review for the speaker and/or component than music that is not of interest to the listener, therefore, the emotional appeal of the source is a factor which can't be ignored. The OP was quite specific in the narrow range of variables that were taken into account and the variable shown lead to only one logical conclusion, that there is no difference between the two components. This is objective evidence and the basis for all scientific study. Without objective evidence presented to the contrary, the claims of the OP can not be properly refuted (if they even should be refuted).

The arguments that have been put forth are subjective, yet they too have merit. Allagoric statements about what has been individually observed is still evidence and is an acceptable logical rebuttal. This still does not change the scientific evidence presented. Based on my subjective testing, additional bass was present when I added external amplification to my speakers, and was specifically greater when listening in pure direct. Several plausible reasons for this that I can come up with:

1) As has been postulated by the OP, I am emotionally attached to my new amp. Perhaps, however, the subjective evidence is too strong for me to willingly agree that this is the case. I think there is something tangibly there, and it isn't occurring at 1 KHz so I think I have some merit here.

2) I have changed some of the variables, such as volume, which has lead me to skew my results in favor of the amp. Again possible, but as has been noted above, there was greater and tighter bass across all listening levels. I have to believe that this is therefore, not likely.

3) Pure Direct listening was used above, and with my Marantz, I also noted the biggest difference here. Well, with Pure Direct you are removing any processing from the receiver and playing the music direct from the source, thru the amps, to the speakers. What this tells me is that the Onkyo does a VERY good job of processing the sound in order to compensate for lack of flat amplification across the audible frequencies. This, to me is the greatest evidence in the inferiority of the Onkyo amp at low volume when compared to outboard amps. Whether or not that matters since you can simply process the music is a different manner.

4) Finally, I would porpose that the Emotiva, my Marantz, and other amplifiers have a lower THD and greater power at lower frequencies than the Onkyo. After all, music is not produced at 1 Khz alone. In fact, the greatest amount of efficiency is in the high frequency, horn-loaded cross-over of the Reference speakers. The lower frequencies, driven by the woofers, require additional juice to produce equal sound quality. My Marantz is rated at 125 watts across the entire band (20 Hz-20KHz), but bench tested at 180 watts when only tested at 1 KHz. I think amplification and THD in the lower ranges is something that the above presented studies are neglegent in not presenting.

[StephenM]

Allagoric statements about what has been individually observed is still evidence and is an acceptable logical rebuttal.

Only if there is some semblance of controls in place. If I listen to a speaker through amp A at an average volume of 60dB and then through amp B at an average volume of 90dB and rave about amp B's greater bass, the test is worthless. As the Stereophile article I posted says: the levels have to be very closely matched in order to have a useful comparison: 0.2dB is enough to throw things off. To get close enough, you need a voltmeter.

I think there is something tangibly there, and it isn't occurring at 1 KHz so I think I have some merit here.

The 5V graphs into 4 and 8 ohms of THD+N I posted for each amplifier were at 10Hz through 50,000Hz, not just 1kHz.. The frequency response graphs show razor flat response from both the Onkyo and the Emotiva to beyond the audible range.