Emotiva XPR-1 vs Bryston 28B SST2 anyone ever compare these? - AVS Forum
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post #1 of 48 Old 07-01-2013, 01:31 PM - Thread Starter
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I am looking to upgrade my current amps (Emotiva XPA-1's). Driving Revel Salon 2's in a smaller room, acoustically treated. Really want to hear from those that have actually heard both and can provide a comparison.
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post #2 of 48 Old 07-02-2013, 06:01 AM
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Originally Posted by Mako71 View Post

I am looking to upgrade my current amps (Emotiva XPA-1's). Driving Revel Salon 2's in a smaller room, acoustically treated. Really want to hear from those that have actually heard both and can provide a comparison.

Congratulations! You have asked a question that is so narrow that it appears unlikely to get an on-topic answer.

Most good amps sound pretty much the same. What's wrong with the sound quality of your current amps?
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post #3 of 48 Old 07-02-2013, 06:36 AM
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I owned a Bryston 3Bsst for quite sometime and can report that it sounded precisely NO different from the NAD receiver, B&K 202+ amp, and Onkyo Receiver (for porch speakers) that I also owned at the time, and the McIntosh MA6600 integrated amp that I have now. ..Arnyk is right. ..Modern amps engineered to be low distortion and linear (which is pretty much ALL of them these days) will be indecipherable from one another. If you upgrade to the Bryston, your system won't sound any better/worse.
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post #4 of 48 Old 07-02-2013, 07:30 AM - Thread Starter
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Hey Arnyk, , "congratulations" yourself for being a real wise guy! The question was sufficiently clear and if you didn't understand it well then I suppose you had no reason to respond in the first place did you?

I disagree with your statement that most good amps pretty much sound the same, but there is no way in hell I am going to have a back and forth with you on that issue, so let's not go there.

Also, I never said there was anything "wrong" with the sound of my current amps. They sound just fine. I was asking the question to get a real response, not some wise blowback.
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post #5 of 48 Old 07-02-2013, 08:22 AM
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Originally Posted by Mako71 View Post


I disagree with your statement that most good amps pretty much sound the same, but there is no way in hell I am going to have a back and forth with you on that issue, so let's not go there.

Most, if not all SS amp makers provide a frequency response graph of their product, and I am willing to bet that both of those products have a linear frequency response. So, what would make them sound different (that is, if we're not talking about driving them to clipping)?
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post #6 of 48 Old 07-02-2013, 08:36 AM
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Originally Posted by Mako71 View Post


I disagree with your statement that most good amps pretty much sound the same, but there is no way in hell I am going to have a back and forth with you on that issue, so let's not go there.

You already did go back and forth with me. And this post does it again rather demeaningly at its end. It also did it in its beginnning, but I did not carry that foreward.
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Also, I never said there was anything "wrong" with the sound of my current amps. They sound just fine.

Then why not change something that would actually make a difference?
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I was asking the question to get a real response, not some wise blowback.

A bite back for the what, fourth time in the same post?

I also see that your factual comments can be correctly summarized as suggesting that you are barking up the wrong tree with your quest for a new amp.
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post #7 of 48 Old 07-02-2013, 09:59 AM
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http://www.matrixhifi.com/contenedor_ppec_eng.htm

http://www.tom-morrow-land.com/tests/ampchall/index.htm

Most amps sound so similar to each other as long as they are being driven within their stated capacity its difficult if not impossible to tell one from the next. I've owned some very powerful amps in the past and have settled on a 175 wpc amp that drives my Emotiva ERTs just fine. I've had a 525wpc amp that sounded no better at the levels I'm listening at. Yes I know - subjective - but isn't all audio subjective?

When all else fails - RTFM!

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post #8 of 48 Old 07-02-2013, 10:56 AM
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Most, if not all SS amp makers provide a frequency response graph of their product, and I am willing to bet that both of those products have a linear frequency response. So, what would make them sound different (that is, if we're not talking about driving them to clipping)?

A not uncommon but hidden source of potentially audible frequency response variations are rarely-given specifications called source impedance and source impedance versus frequency.

Many tubed and some SS amplifiers have nonlinear distortion aside from clipping that is strongly dependent on frequency.

Historically these performance areas have been consistent enough across the mainstream marketplace but they have become more unpredictable with switchmode amplifiers.
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post #9 of 48 Old 07-02-2013, 10:58 AM
 
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Originally Posted by arnyk View Post

I also see that your factual comments can be correctly summarized as suggesting that you are barking up the wrong tree with your quest for a new amp.
This is the kind of post he wants:
"Took delivery of the XPR-1s on Saturday and spend a while hooking them up. They’re bruts to move around!
...

So…here’s what I hear.
1. Music sound immediately became more “relaxed”; “unstrained”. I’ve heard that expression before but now I know what that sounds like!
2. Sound stage “opened” considerably and there was an added level of 3-dimensional clarity and space (assume this is a combination of power and frequency response which takes advantage of the KEF speaker high end of 60K Hz)
3. High frequencies sound “delicate”; sweet. (absence of edges and distortion)
4. Bass response (SPL) increased noticeably and solidified (tightened) from mid-bass down; no doubt due to the added power; no stain what-so-ever
5. Bass notes warmed and became more tonal; especially on instruments like bass fiddle and the like
6. Sound stage enlarged and clarified; notes seemed to “hang” in space; wonderful; love it!
7. Sound is more “impactful” at lower SPL levels; more power, more dynamic at low volumes (with the XPA1s, “live” impact only occurred at high volume)

I thought I was near perfection with the 500W XPA-1s but I now hear a level of clarity and sound in my music which allows me to hear things I’ve never heard before. This amp definitely ups the ante for the audiophile. ...
"
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Exactly the type of in depth response I was looking for. Many thanks!
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Here is another vote for Emotiva XPA 1's. I have 3 running my newly acquired Salon 2's and my Mythos 10 center channel. Tremendous headroom. Sounds very dynamic yet smooth. Ultimately try out as many as you can and decide. Emo is a safe bet with their return policy, although I doubt you will want to once you've heard them.
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Running XPA -1's with my Revel Salon 2's. Wondering if the XPR-1 would be better.
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Selling three XPA 1's.
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post #10 of 48 Old 07-02-2013, 11:19 AM - Thread Starter
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Yeah, you figured it out.
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post #11 of 48 Old 07-02-2013, 11:26 AM
 
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Yeah, you figured it out.
There are many audio forums out there that you will love. Too many to name but one isn't named something... "Science" forum.
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post #12 of 48 Old 07-02-2013, 12:05 PM
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I say if someone wants to spend $20k let the fool be parted from his money. This conversation will go nowhere.
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post #13 of 48 Old 07-02-2013, 12:17 PM
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Originally Posted by arnyk View Post

A not uncommon but hidden source of potentially audible frequency response variations are rarely-given specifications called source impedance and source impedance versus frequency.

Many tubed and some SS amplifiers have nonlinear distortion aside from clipping that is strongly dependent on frequency.

Historically these performance areas have been consistent enough across the mainstream marketplace but they have become more unpredictable with switchmode amplifiers.

Good to know. smile.gif
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post #14 of 48 Old 07-02-2013, 12:21 PM
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Then why not change something that would actually make a difference?

I wish more people would heed that advice.
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post #15 of 48 Old 07-02-2013, 02:40 PM
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Post #9 submitted for "Best of Internet" Awards. wink.gif
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post #16 of 48 Old 07-03-2013, 03:25 PM
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Anyone who thinks an Emotiva amplifier sounds as good as a Bryston is almost certainly trying them out with some mediocre associated equipment that does not allow the rather substantial difference to be heard.

A Ferrari might be unimpressive if hampered by a cheap set of tires. Its engine alone is not capable without the proper suspension, tires, transmission etc. One cannot evaluate the engine alone without properly matched components.

The same is true of a power amplifier.

Using it in a system of top-quality equipment will make it quite clear to virtually ANYONE who listens for a few minutes that Bryston amplifiers are capable of sound quality that is far superior to Emotiva and 95% of the other amplifiers on the market.

If one has other components that are mediocre, a Bryston amplifier cannot audibly perform properly, so there is no point in buying it. By all means, save your money and buy the cheap amplifier in that case.

The system cannot sound better than the weakest link in the audio reproduction chain.
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post #17 of 48 Old 07-03-2013, 03:50 PM
 
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Originally Posted by commsysman View Post

Anyone who thinks an Emotiva amplifier sounds as good as a Bryston is almost certainly trying them out with some mediocre associated equipment that does not allow the rather substantial difference to be heard.

A Ferrari might be unimpressive if hampered by a cheap set of tires. Its engine alone is not capable without the proper suspension, tires, transmission etc. One cannot evaluate the engine alone without properly matched components.

The same is true of a power amplifier.

Using it in a system of top-quality equipment will make it quite clear to virtually ANYONE who listens for a few minutes that Bryston amplifiers are capable of sound quality that is far superior to Emotiva and 95% of the other amplifiers on the market.
That's what happens when you try to use Radio Shack SPL meter for level matching. It's not precise enough.
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I have one of the old Radio Shack SPL meters, and we matched the levels using the Stereophile test disc tones.


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If one has other components that are mediocre, a Bryston amplifier cannot audibly perform properly, so there is no point in buying it. By all means, save your money and buy the cheap amplifier in that case.

The system cannot sound better than the weakest link in the audio reproduction chain.
And the amp isn't the weakest link these days.
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post #18 of 48 Old 07-03-2013, 03:56 PM
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As long as you continue to use sophistry as a substitute for logical reasoning, you will continue to demonstrate that you have no credibility to any intelligent person.

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That's what happens when you try to use Radio Shack SPL meter for level matching. It's not precise enough.
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post #19 of 48 Old 07-03-2013, 04:09 PM
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As long as I continue to use sophistry as a substitute for logical reasoning, I will continue to demonstrate that I have no credibility to any intelligent person.

Fixed that for you.
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post #20 of 48 Old 07-03-2013, 04:11 PM
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Quote:
Originally Posted by commsysman View Post

Anyone who thinks an Emotiva amplifier sounds as good as a Bryston is almost certainly trying them out with some mediocre associated equipment that does not allow the rather substantial difference to be heard.

A Ferrari might be unimpressive if hampered by a cheap set of tires. Its engine alone is not capable without the proper suspension, tires, transmission etc. One cannot evaluate the engine alone without properly matched components.

The same is true of a power amplifier.

Using it in a system of top-quality equipment will make it quite clear to virtually ANYONE who listens for a few minutes that Bryston amplifiers are capable of sound quality that is far superior to Emotiva and 95% of the other amplifiers on the market.

If one has other components that are mediocre, a Bryston amplifier cannot audibly perform properly, so there is no point in buying it. By all means, save your money and buy the cheap amplifier in that case.

The system cannot sound better than the weakest link in the audio reproduction chain.

As a retired EE professor, what measurements would you suggest one do in order to best capture these sound differences?
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post #21 of 48 Old 07-03-2013, 07:35 PM
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s a retired EE professor, what measurements would you suggest one do in order to best capture these sound differences?

sorry prof, you are dealing with audiophilitis, where measurements are sign of objectivism, which is really really bad, and measurements tell you NOTHING; you have to trust your ears, your wife exclaiming various profundities, your friends in green with envy and the mailmen spilling the milk - or is it the milkmen spilling the mail? upon approaching your house listening to the speakers blaring some Pawnshop music...
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post #22 of 48 Old 07-03-2013, 09:14 PM
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Originally Posted by commsysman View Post

Anyone who thinks an Emotiva amplifier sounds as good as a Bryston is almost certainly trying them out with some mediocre associated equipment that does not allow the rather substantial difference to be heard.

A Ferrari might be unimpressive if hampered by a cheap set of tires. Its engine alone is not capable without the proper suspension, tires, transmission etc. One cannot evaluate the engine alone without properly matched components.

The same is true of a power amplifier.

Using it in a system of top-quality equipment will make it quite clear to virtually ANYONE who listens for a few minutes that Bryston amplifiers are capable of sound quality that is far superior to Emotiva and 95% of the other amplifiers on the market.

If one has other components that are mediocre, a Bryston amplifier cannot audibly perform properly, so there is no point in buying it. By all means, save your money and buy the cheap amplifier in that case.

The system cannot sound better than the weakest link in the audio reproduction chain.

But, what makes one well-designed amp that is performing within specs automatically inferior to one that is also performing to specs, when virtually every SS amp has a flat frequency response?

Please. I want to know. All I read from you is these huge pronouncements from you that we're all ignorant, in the dark. You also seem to discount every bit of information gathered by those who are educated within this field too.

So, again, how can you prove that all of these people are so wrong?

Could you demonstrate this in a DBT ABX test? And, yes, I mean a real DBT ABX test. You seem to suggest that this is the case, when you say that "virtually ANYONE" can tell the difference.

So it should be obvious, right? If it's that obvious - any test should show that? If I am wrong - in what way am I wrong?

Do you know that this has been done before? And if so, do you know what the results were?
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post #23 of 48 Old 07-03-2013, 10:32 PM
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Originally Posted by Mako71 View Post

Hey Arnyk, , "congratulations" yourself for being a real wise guy! The question was sufficiently clear and if you didn't understand it well then I suppose you had no reason to respond in the first place did you?

I disagree with your statement that most good amps pretty much sound the same, but there is no way in hell I am going to have a back and forth with you on that issue, so let's not go there.

Also, I never said there was anything "wrong" with the sound of my current amps. They sound just fine. I was asking the question to get a real response, not some wise blowback.

 

Better amps have little to no audible distortion and, when they aren't presented with loads beyond their capabilities, they definitely sound pretty much the same. Hypocritical, personal invective doesn't change this fact.

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post #24 of 48 Old 07-04-2013, 12:25 AM
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"Better" isn't synonymous with "most expensive".

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"Better" isn't synonymous with "most expensive".

agreed! however certain folks never will understand this....just take a look at post #16.tongue.gif
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post #26 of 48 Old 07-04-2013, 07:30 AM
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Virtually every S/S amplifier has a flat frequency response when tested with a RESISTOR for a load. That is like testing a car on a dynamometer and claiming you know everything there is to know about that car from that one test.

If you had any experience in audio engineering, you would be very much aware that a SPEAKER is a complex load that has substantial amounts of inductive or capacitive reactance, and an impedance that is NOT linear.

The ability of an amplifier to drive that sort of load is a whole different thing, and requires a lot of attention to power supply design and amplifier design to prevent distortion.

ANY engineer that has EVER designed an amplifier KNOWS exactly what I am talking about, and your repeated statements indicating your complete ignorance of these BASIC design and performance issues serves no purpose. I don't know who "those people" are, but they sure as hell are not competent amplifier design engineers!!!

The most expensive amplifier is not always the best amplifier, but the design decisions required to make a relatively cheap amplifier pretty much guarantee poor performance in the real world (driving REAL speaker systems).



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But, what makes one well-designed amp that is performing within specs automatically inferior to one that is also performing to specs, when virtually every SS amp has a flat frequency response?

Please. I want to know. All I read from you is these huge pronouncements from you that we're all ignorant, in the dark. You also seem to discount every bit of information gathered by those who are educated within this field too.

So, again, how can you prove that all of these people are so wrong?

Could you demonstrate this in a DBT ABX test? And, yes, I mean a real DBT ABX test. You seem to suggest that this is the case, when you say that "virtually ANYONE" can tell the difference.

So it should be obvious, right? If it's that obvious - any test should show that? If I am wrong - in what way am I wrong?

Do you know that this has been done before? And if so, do you know what the results were?
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post #27 of 48 Old 07-04-2013, 07:41 AM
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It is actually fairly simple to connect an actual speaker system to an actual amplifier, and using a signal generator as a source, measure the frequency response and distortion of the amplifier with that load over the audio band with an oscilloscope and Distortion Analyzer.

John Atkinson does a distortion analysis for every amplifier that is reviewed in the magazine Stereophile and publishes the detailed results. Since a good distortion analyzer costs $30K and more, and requires considerable expertise and experience to use properly, it is not surprising that magazines do not usually do this. He points out the shortcomings of each amplifier, and the wise will do well to heed his analysis before purchasing an amplifier.

You would probably learn a lot if you were to read 10 or 20 of his amplifier test reports from past issues COMPLETELY AND CAREFULLY and let the information sink in a bit. It is obvious that you have never done so in the past. Educate yourself a bit and your questions and statements will possibly make more sense. I am always amused when people criticize Stereophile as being a purely subjective magazine, when they do much more objective scientific performance testing of products than any other. They obviously are not reading the whole article.

This is how amplifier design engineers do it, and if you were to do so you would find that the differences between amplifiers are quite significant and measureable.

Using the complex load of an actual speaker to test the amplifier will reveal the shortcomings of the amplifier very quickly, while a test with a resistive load will only give some information.

The amplifier performance will be different with every speaker, since some speakers have a greater degree of impedance variation and reactances than others.

Better-designed amplifiers, however, will perform better, maintaining more linear gain and producing less distortion, even with those speakers that are a more difficult load to drive.


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As a retired EE professor, what measurements would you suggest one do in order to best capture these sound differences?
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post #28 of 48 Old 07-04-2013, 08:29 AM
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Originally Posted by commsysman View Post

Virtually every S/S amplifier has a flat frequency response when tested with a RESISTOR for a load. That is like testing a car on a dynamometer and claiming you know everything there is to know about that car from that one test.

If you had any experience in audio engineering, you would be very much aware that a SPEAKER is a complex load that has substantial amounts of inductive or capacitive reactance, and an impedance that is NOT linear.

The ability of an amplifier to drive that sort of load is a whole different thing, and requires a lot of attention to power supply design and amplifier design to prevent distortion.

ANY engineer that has EVER designed an amplifier KNOWS exactly what I am talking about, and your repeated statements indicating your complete ignorance of these BASIC design and performance issues serves no purpose.

The most expensive amplifier is not always the best amplifier, but the design decisions required to make a relatively cheap amplifier pretty much guarantee poor performance in the real world (driving REAL speaker systems).




can you show me the poor design decisions in the less expensive amplifier between the two in question:

emotiva xpr-1


bryston 28b sst2




Furthermore, can you identify audible differences between these two amps in question in a proper double blind test? if so, can you identify the more expensive one vs. the less costly unit?


---also based on your statement "relatively cheap amplifier pretty much guarantee poor performance in the real world (driving REAL speaker systems)." i guess my speakers are fake, since i am driving them with an inexpensive amp....as i can most certainly state the my performance is not poor as you guarantee, therefor my speakers must be fake!
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post #29 of 48 Old 07-04-2013, 12:34 PM
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It is actually fairly simple to connect an actual speaker system to an actual amplifier, and using a signal generator as a source, measure the frequency response and distortion of the amplifier with that load over the audio band with an oscilloscope and Distortion Analyzer.

Right.
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John Atkinson does a distortion analysis for every amplifier that is reviewed in the magazine Stereophile and publishes the detailed results.

More to the point of this discussion, he also does frequency response tests with both resistive loads and loads that simulate loudspeakers.
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Since a good distortion analyzer costs $30K and more, and requires considerable expertise and experience to use properly, it is not surprising that magazines do not usually do this. He points out the shortcomings of each amplifier, and the wise will do well to heed his analysis before purchasing an amplifier.

This is a false claim on a number of grounds. Measuring the frequency response of an amplifier with a resistive load, simulated loudspeaker load, or actual loudspeaker load does not require a $30k audio analyzer, which I might add I have two on hand. They are nice to have but they are not required. They don't take an engineering degree to use, either. A very low distortion source is not needed. If you know what you are doing, and are willing to take a little time a source with flat response is not needed. You don't even need a meter with good frequency response since the essence of the measurement is a comparison.

You don't have to spend a ton of money to obtain a SS power amp with good frequency response into either a resistive or loudspeaker load. Loudspeaker loads are more challenging for toobed amps.

Finally, since a modern audio system will be based on an AVR with automated room optimization software that automatically corrects the in-room frequency response as required, the power amp circuitry's unadjusted frequency response will be corrected during the installation of the AVR.
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post #30 of 48 Old 07-04-2013, 01:13 PM
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Originally Posted by commsysman View Post

It is actually fairly simple to connect an actual speaker system to an actual amplifier, and using a signal generator as a source, measure the frequency response and distortion of the amplifier with that load over the audio band with an oscilloscope and Distortion Analyzer.
You only need a decent soundcard in your desktop and free software such as REW, Rightmark, Holm or ARTA.
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