All transports are NOT the same

[mtrycraft]

I don't want to laugh out loud at your comments, because, they do indicate a lack of understanding of the basics. I have tried to get you to see this, but it doesn't seem to be working. You cannot just read Stereophile, talk to some audio salon salesmen, and think you have it all figured out. Some work and study really is required. I think you could do it if you try.

Of couse you can show that I am a misguided moron if you simply tell us what measured performance factors are not irrelavant in judging amp performance. What are they?

He has been brainwashed for 30 years. No hope left.

[mtrycraft]

I base my comments upon direct experience.

Yep, so do alien abductees customers of psychic readings, etc. Why would audio be expemt from bs, unreliable perception, even after 30 years?

They build components on that which they find works best.

Or, what the gullibl eaudiophile will buy.


The Crown IC-150 preamp was the poster child for negative feedback gone amok leading to egregious amounts of TIM/SID.

More audio hype, voodoo.
http://www.dself.dsl.pipex.com/ampins/dipa/dipa.htm

I winder where TIM/SID is?


Yet it had something like 0.005 THD. Totally useless.

You are entitled to that opinion. But some are better than others.



You know nothing of my experience. I haven't been to an audio salon in years. I base my comments on direct experience to some very nice equipment.

Of course those experiences are fact filled and reliable, right?

[Sealed]

If you are new to the world of home audio, here is how to tell you are being misled by a highender in regard to amps:

1) They mention the word "detailed". This is a fairly meainingless which could relate to accuracy, but implies that they can hear more.
--DUH. I have been in this game since 1986. I know precisely what I said, and what I meant. The superior opamps do deliver detail that the cheaper opamps smear away. They do not have the slew rate, nor the transient speed. It's like sound through jello vs through steel. A more efficient transmitter.


Remember this: amps to not create sounds, (if you're lucky)--they deal strictly with electrical signals. The distortion of a signal is the difference between the input and the output. Low distortion means the output signal is virtually the same as the input. No "detail" is involved.

--Did I ever imply that? No. You are simply taking a soapbox, and condescending withought knowing my background or what I have done. Simple ego puffery and pretense. I really, really hope you are explaining things to someone other than me, because you are preaching to the choir.


2) They mention the words "slow" or "fast". My amp cannot move, it is stationary. What could they mean? The rate at which the amp can change its output level? That's slew rate, it is more than adequte for most home amps. (Do you doubt you amp can respond faster that the orchestra?) My amp can respond to 20 KHz signal ( more like 100 KHz)--which moves its output up and down 20,000 times a second. Pretty fast! The use of speed words in talking about an amp is indicative of high-end muddled thinking. Run for the hills when you hear it!

--Or it's indicitive of your lack of real understanding about the interaction of components and circuitry. The cheaper opamps are again, of less fidelity, and less transient speed. This is clearly visible on a tectronix o'scope, and clearly audible.


3) When they talk aboout soundstage in regard to an amp. This is mind numbing.
--Only to those with numb minds

You get your 3D cues by slight sound time delays and volume levels between the two speakers. The response and location of you speakers' greatly affect the 3D effect (in addition to your room.) Your amp can't effect sound stage unless it is messing up the two channels with time or level imbalances. All properly perfoming amps don't do that. Duh! I have heard scads of amps and speakers, amps don't affect soundstage (they can't), speakers do.

--Yes they do Eienstien. The source will determine what the speakers can reproduce. Else you are saying all sources, lp, cd, sacd, dvd-a sound exactly the same. The soundstage is a 3 dimensional reproduction of the electrical signal (audio) as it's fed to the final transducer (speaker) I really wish you'd learn what you are talking about before you soap box. You clearly have a sophomoric understanding of very basic, simple math and simple sales-droid logic. You havce obviously never even pulled the cover off a component, swapped parts or even examined a schematic.

4) When they talk "mass market" and make statements like "breathing life" into your system it should be clear that they are coming from a high-end, irrational perspective. You can't blame them, this stuff is all over the subjectivist magizines. So, hey, they read it in a mag, so it must be true. Darn if they can't begin to hear it in their overly expensive electronics.

--I know it's a tough concept for your weak mind to wrap around. I know there are one billion more concrete terms to use. When a system is formerly dull, lifeless, and opaque because of sheer lack of resoloution or speed, then you upgrade the cheap parts installed to make a price point to those normally found in better components, you wake the part up. This is like building an engine for peak performance instead of everyday mileage. You are so wrong in so many areas. Does your head fit through doorways?

If you made it to this response, you have heard that nobody (I have heard of in over 20 years in home audio) has demontrated that they can tell amps apart (note that not everyone has been tested).
--You need to get out of the old age home. You guys over 45 have acute hearing loss. If you can't tell the difference between a cary SET and a krell KSA, get out of the hobby.


If that seems problematical to you in light of comments made about the clear differences in speed, detail, soundstange, and life in your amp, then proceed to ignore such statements. Join the rational audio club, you will save money and get BETTER sound.

You have no clue. You are obviously one of the sheer incompetant dipshi7s that must BUY his way into better sound, but cannot decipher an amp from an ohm from a volt from a watt in a formula without cut & paste from the net. Such a feeble minded lemming you are. You should get an audiometric exam, you are obviously tone deaf to add to your sheer lack of knowledge and understanding.

[Sealed]

[QUOTE=RobotCzar]THD AND FREQUENCY RESPONSE OF THE ELECTRICAL SIGNAL TELL THE WHOLE STORY FOR ELECTRONICS (PROVIDED MEASUREMENTS ARE MADE AT ENOUGHT DATA POINTS, I.E., FREQUENCIES, POWER LEVELS, AND LOADS. THERE ISN'T ANYTHING ELSE FROM A PHYSICS/ELECTRONICS PERSPECTIVE.
REPEAT: DYNAMIC DISTORTION IS PROVEN TO BE ENCORPORATED IN THD MEASUREMENTS AT HIGH FREQUENCIES. AUDIO ELECTRICAL SIGNALS ARE MERELY COMBINATIONS OF PURE TONES YOU CALL "STEADY STATE".

I ACCEPT THAT YOU WILL NOT LISTEN TO ME AND HAVE ASKED YOU TO FIND AN EXPERT YOU TRUST. YOU ARE RELYING TOO MUCH ON YOUR EXPERIENCES AND THE STATEMENTS OF CULTISTS SUCH AS THE PEOPLE YOU MENTION.
QUOTE]


AND I AM ONLY USING CAPSLOCK BECAUSE YOUR DUMB A$$ DID. GET A CLUE MORON. AND YOU HAVE NO CLUE WHAT ANY OF THEM ACTUALLY MEAN OR WHAT ALL OF THE MEASUREMENTS ACTUALLY ARE. WITHOUT CUTTING AND PASTING YOU'D NOT BE ABLE TO TELL ME THE DIFFERENCE IN THE OPAMP CONSTRUCTION, WHAT TIM AND SLEW RATE ACTUALLY ARE. YOU FANCY YOURSELF A NELSON PASS WANNABE, BUT COME OFF AS A CLUELESS FLAT EARTH A$$.

YOUR BRAIN IS A COMBINATION OF PURE TONES WITH NO HARMONICS TOO. OBVIOUSLY INCAPABABLE OF ANYTHING MORE THAN ELEMENTARY ELECTRONICS AND LOGIC. GO BACK TO SCHOOL, AND LEARN THIS TIME.

[WmAx]

It is based upon an average of readings using steady state test tones. Instantaneous distortion is masked. In case you don't understand otherwise, music is a wee bit more complex than steady state tones. The Crown IC-150 preamp was the poster child for negative feedback gone amok leading to egregious amounts of TIM/SID. That is why high frequency reproduction with that turkey sounds like fingernails on a chaulkboard. Yet it had something like 0.005 THD. Totally useless.

TIM distortion is a 'real' phenomena, given the correct perspective. TIM appears to be an expression of high frequency non-linearity of a gain stage. It is not caused by negative feedback except when the slew rate of the circuit is not adequate to keep up. IF one exceeds the bandwidth determined mathematically by the slew rate the result is rapidly increasing high frequency non-linearity that is highly dynamic, since the higher voltage output the higher the distortion when slew limiting sets in. Modern circuits have no such issues when used within proper established design theory considering the bandwidth/feedback/slew-rate. Proper THD measurements at enough datapoints reveal this 'TIM' as it is somewhat improperly called, since it's not really a distinct distortion, but seemingly a combination of non linearities. However, more complex procedural testing as has been described in various documents on how to test 'TIM' distortion specifically, these can be potentinally used to reveal further details about the base source/origin of the non linear distortion if that is important to the circuit designer. Not to be confused with audibility.

20 years or more ago, it was time-consuming to produce detailed THD plots of various conditions(differring amplitudes/loads/frequencies/etc.). Today, such can be done easily and efficiently with moderan automated signal analysis equipment.

Here is a plot of a once common audio IC 20 or more years ago, with grossly indadequate slew-rate resulting in high levels non-linear behaviour at risig frequencies but would result in 'very good' measurements if useless static THD measurements were made, at which time would observe a standard 1kHz THD value, which in this case would result in 0.015% reading for this device. Hoewver, observation of this detailed THD plot makes the true results apparent.



Here are teh results for a modern audio purposed produced op-amp that is considered to be one of the mediocre designs on the market as far as technical performance, but yet has no potentially audible signficnat problems with high frequency non-linearity. I could refer to very good examples that have magnitudes lower distortion then this, but I wanted to give a worst-case scenario for a device you might commonly find in a mass consumer product:



The multiple plots are represeantive of different termination loads and specified in large numbers on the left. (680=680 Ohms, 1k=1kohms, etc.).

-Chris

[WmAx]

BTW, the 'poor' graph is of a typical 741 operational amplifier with a 0.5 v/us slew rate. The Crown IC-150 is referred to as having a 709 operational amplifier. This was the first mass produced audio op-amp, and it's slew rate was about half that of the 741, at around 0.25 v/us. Totally inadequate for the audio band -- it made the 741 look like a linear device!

-Chris

[E-Stat]

REPEAT: DYNAMIC DISTORTION IS PROVEN TO BE ENCORPORATED IN THD MEASUREMENTS AT HIGH FREQUENCIES. AUDIO ELECTRICAL SIGNALS ARE MERELY COMBINATIONS OF PURE TONES YOU CALL "STEADY STATE".

Another factor I failed to mention in my first post is that THD lumps all the spectra together without acknowledging the well known fact that odd order harmonics are interpreted by the brain as dissonant where even ones are not. May you be sentenced to life listening to a Crown ICCCCH-150.

I ACCEPT THAT YOU WILL NOT LISTEN TO ME AND HAVE ASKED YOU TO FIND AN EXPERT YOU TRUST. YOU ARE RELYING TOO MUCH ON YOUR EXPERIENCES AND THE STATEMENTS OF CULTISTS SUCH AS THE PEOPLE YOU MENTION.

My friend, thirty years of listening to live music and music reproduced on very high resolution systems will trump your simplistic notions in a heartbeat.

I take your response to be that high end amps have lower dynamic distortion and that this distortion is audible at the level found in typical, non high end, amps. I disagree on all counts, but at least you are saying something other than your "experiences".

Let's try again. What I said was that THD lumps and averages all distortion over time into a single convenient figure that does not correlate to musical fidelity. I have heard amps with great THD specs and horrible sound. The search for the holy grail of lowering THD readings by using copious amounts of negative feedback was proven to be folly and is not done anymore. Ironically, the amps I find most musical tend to have higher THD figures, most certainly my tube amps.

I'm really curious as to your point of reference. What is the system you find most musicallly truthful? It does not have to be your own. I'm wondering if you have the confidence of skeptic and the Monster to provide such information, or the total lack thereof as with our resident class clown.

rw

[E-Stat]

Why would audio be expemt from bs, unreliable perception, even after 30 years?

Only a person who has a deep love of and long term experience with listening to live music would understand. I find it sad that is something you will likely never understand.

rw

[E-Stat]

"Fine and dandy, but we haven't approached perfection yet."

How do you know?

I have yet to hear a single amp or preamp that trumps every other challenger in every way. I find that the best tubes provide me the best set of musical compromises especially with the critical midrange. While the best SS designs I've heard don't equal tubes in that respect, some do have better response at the frequency extremes.

MOSFET designs are said to bridge the traditional strong points of both designs. The GamuT single MOSFET amps are very musical indeed, yet I do not find them as musically truthful as my VTLs . I note that you use a MOSFET amp.

Do tell me of a perfect amp. I'd love to hear it.

rw

[RobotCzar]

Another factor I failed to mention in my first post is that THD lumps all the spectra together without acknowledging the well known fact that odd order harmonics are interpreted by the brain as dissonant where even ones are not. May you be sentenced to life listening to a Crown ICCCCH-150.

My friend, thirty years of listening to live music and music reproduced on very high resolution systems will trump your simplistic notions in a heartbeat.

Let's try again. What I said was that THD lumps and averages all distortion over time into a single convenient figure that does not correlate to musical fidelity. I have heard amps with great THD specs and horrible sound. The search for the holy grail of lowering THD readings by using copious amounts of negative feedback was proven to be folly and is not done anymore. Ironically, the amps I find most musical tend to have higher THD figures, most certainly my tube amps.

I'm really curious as to your point of reference. What is the system you find most musicallly truthful? It does not have to be your own. I'm wondering if you have the confidence of skeptic and the Monster to provide such information, or the total lack thereof as with our resident class clown.

rw

Well, thanks for not deteriorating into a raving lunatic as at least one other has done. It would be helpful if you answered the issues I have raised instead of just running on to other misconceptions.

As you can see from the previous response, THD can be used to assess dynamic distortion, as I claimed. The specific data in that post also clearly calls into question your assertion that opamps have audible dynamic distortion. The wrongness of your comments could not be better proven wrong in this type of forum. Why not admit it?
No one is suggesting that one THD measurement is sufficient to judge the performance of a power amp.

Now, you have ignored what I said about distortion, you have ignored what I said about using test tones, let's move on to the another favorite of high-end nonsense: odd-order harmonics. No doubt that some solid state amps have higher odd-order harmonics than tube ones (the correlation between even and odd harmonics in extremely expensive solid state amps is not established and I have not heard of expensive amps necessarily measuring differently that cheap ones in regard to the character of the harmonics). The real point, of course, is that the SUM of all the harmonics (e.g., THD) is so low that the nature of the harmonics in the distortion are irrelavant (because they are inaudible). Does that make any sense to you?

I have been listening to home audio for 30 years and I have also been listening to misinformation spread by those who are into audio for ego purposes. A symptom of this ego is the "my system is better than yours..." claim. It probably isn't, but it surely is more expensive. Reports and claims from audiophiles are proven to be extremely unreliable--is there any reason to think yours are different?

The music system I find most musically truthful is Orchestra Hall. No home audio system sounds quite like it, but some come closer than others. None approaches "truth" or even can because the acoustic environment in which the system operates is the biggest factor affecting what is heard. If you could reconsider your beliefs you would get really better sonic results, not merely a feeling of satisfaction at your equipment.

[RobotCzar]

You have no clue. You are obviously one of the sheer incompetant dipshi7s that must BUY his way into better sound, but cannot decipher an amp from an ohm from a volt from a watt in a formula without cut & paste from the net. Such a feeble minded lemming you are. You should get an audiometric exam, you are obviously tone deaf to add to your sheer lack of knowledge and understanding.

I merely note that no matter how long you have been using terms that are meaningless, they don't become meaningful. That is why you can't define them. That is also why you must resort to name calling.

The oldest trick in the book is for boys to get together and make up words that only the in-group "understands" (priests were probably the first, but teenagers seem to do it naturally). Using these words makes one seem smart, as if nobody outside the group really "gets" it. I am not sorry to point out that these words have no meaning technically. The weakness of your defense of them merely points out how useless these made-up words really are. Stringing more together like "transient speed" really doesn't help.

You might stop to consider that maybe I have a point before you get all defensive and offensive about this. We all make mistakes, the only real mistake is to not learn from our errors and change.

[RobotCzar]

TIM distortion is a 'real' phenomena, given the correct perspective. TIM appears to be an expression of high frequency non-linearity of a gain stage. It is not caused by negative feedback except when the slew rate of the circuit is not adequate to keep up. IF one exceeds the bandwidth determined mathematically by the slew rate the result is rapidly increasing high frequency non-linearity that is highly dynamic, since the higher voltage output the higher the distortion when slew limiting sets in. Modern circuits have no such issues when used within proper established design theory considering the bandwidth/feedback/slew-rate. Proper THD measurements at enough datapoints reveal this 'TIM' as it is somewhat improperly called, since it's not really a distinct distortion, but seemingly a combination of non linearities. However, more complex procedural testing as has been described in various documents on how to test 'TIM' distortion specifically, these can be potentinally used to reveal further details about the base source/origin of the non linear distortion if that is important to the circuit designer. Not to be confused with audibility....

-Chris

Wow. Thank you, thank you, for a rational response with real data and information in it. I learned something new and useful from AR! Well, alright!

If I may be so bold as to add just a bit to your wonderful post? You said "'TIM' as it is somewhat improperly called, since it's not really a distinct distortion" I merely want to expand a bit on that by saying that there really aren't different "kinds" of distortion. Distortion is defined as the differencce (minus gain) between the input and output signal. Audiophlies get confused because of the labeling of "types" of distortion such as THD, IM, TIM, crossover, etc. These terms refer mainly to how distortion is measured (e.g., by measuring all harmonic of a sine = THD) or the source of distorion (crossover).

I think it helps non-technical people sort this all out if they understand that distortion is distortion and that it contains all that is unwanted in an electronic signal.

[Sealed]

I merely note that no matter how long you have been using terms that are meaningless, they don't become meaningful. That is why you can't define them. That is also why you must resort to name calling.

The oldest trick in the book is for boys to get together and make up words that only the in-group "understands" (priests were probably the first, but teenagers seem to do it naturally). Using these words makes one seem smart, as if nobody outside the group really "gets" it. I am not sorry to point out that these words have no meaning technically. The weakness of your defense of them merely points out how useless these made-up words really are. Stringing more together like "transient speed" really doesn't help.

You might stop to consider that maybe I have a point before you get all defensive and offensive about this. We all make mistakes, the only real mistake is to not learn from our errors and change.

Nah, you are just a deaf, clueless, boy-raping POS with zero electronic knowledge, and wax-filled ears. You wouldn't know circuit city from Wilson if it was given to you.

You are a totally lost moron, with his head rammed up his butt so far he can see out his own mouth.

You should shut up, because it's obvious you have zero knowledge.

[WmAx]

Nah, you are just a deaf, clueless, boy-raping POS with zero electronic knowledge, and wax-filled ears. You wouldn't know circuit city from Wilson if it was given to you.

You are a totally lost moron, with his head rammed up his butt so far he can see out his own mouth.

You should shut up, because it's obvious you have zero knowledge.

I see place for sarcasm, definitive nouns(accuratey describing behaviour) or other methods of 'insult' of poking 'fun' at the actual issues at hand if done properly and within the proper scope on a forum. However, what you have done here is to resort to petty name calling that is not based on observable traits of the person you are responding. Or do you have substantiatino he is a boy-raping POS? Why not point out exactly what parts of his demonstrated electronic knowledge is wrong? Or is the extent of your capability limited to weak "I said so" type arguments?


-Chris

[E-Stat]

Well, thanks for not deteriorating into a raving lunatic as at least one other has done.

You're welcome. I see nothing to be gained by lowering the tone of the discussion.

It would be helpful if you answered the issues I have raised instead of just running on to other misconceptions.

You just "shouted" simplistic notions with no proof of any kind, be it observational or otherwise.

As you can see from the previous response, THD can be used to assess dynamic distortion, as I claimed.

Surely you jest. Are you suggesting that Chris' two graphs are conclusive proof that such provides a clear picture of dynamic behavior?

The specific data in that post also clearly calls into question your assertion that opamps have audible dynamic distortion. The wrongness of your comments could not be better proven wrong in this type of forum. Why not admit it?

Do tell me of an op amp based circuit that is so perfect it's distortion is inaudible in reproducing musical content. This is really going to be quite amusing!

No one is suggesting that one THD measurement is sufficient to judge the performance of a power amp.

I'm glad you acknowledge that. I'd say that is progress.

Now, you have ignored what I said about distortion, you have ignored what I said about using test tones, let's move on to the another favorite of high-end nonsense: odd-order harmonics.

I ignore your simplistic assertions to a complex problem. As for harmonic spectra, an analogy would be looking at total cholesterol and attemping to make a health based judgement without analyzing the HDL content vs. LDL content.

The real point, of course, is that the SUM of all the harmonics (e.g., THD) is so low that the nature of the harmonics in the distortion are irrelavant (because they are inaudible). Does that make any sense to you?

It would make sense if it were true. Again, do tell me of your perfect amp with inaudible distortion.

I have been listening to home audio for 30 years and I have also been listening to misinformation spread by those who are into audio for ego purposes.

As have I having worked in audio during college. You are conversing with a different sort of person.

A symptom of this ego is the "my system is better than yours..." claim. It probably isn't, but it surely is more expensive. Reports and claims from audiophiles are proven to be extremely unreliable--is there any reason to think yours are different?

Let's read my request again and see if you get it this time:

I'm really curious as to your point of reference. What is the system you find most musicallly truthful? It does not have to be your own.

Did you notice I did not ask you about your system? I don't really care what you own. What I am curious to understand is just what I said - your point of reference. I'm sorry you find your position so weak as to dodge the question. I hold higher esteem for those who have more confidence in their beliefs.

If you could reconsider your beliefs you would get really better sonic results, not merely a feeling of satisfaction at your equipment.

To which beliefs are you referring? How is it I will get better sonic results? I'm all ears.

rw

[RobotCzar]

E-Stat, Ok, I give up trying to reason with you. Obviously neither logic or data are meaningful to you. Name plates, however, are--or you would not be asking for name dropping. You have offered NO evdience or even a meager defense for your (borrowed) ideas. You must realize that you are spouting age-old high-end nonsense and bad analogies and ignoring points I have tried to explain regarding basic physics and electronics. (If my total cholesterol were low enough it would not matter what percentage of it was good or bad--your own analogy doesn't work for your argument.) It is kind of sad to see people taken in by high end technobabble, but you can't help someone who doesn't want to be helped.

I tried to imply (perhaps too subtlely) that the only sonic truth is a live performance. You may be inexperienced in listening to live music, so you perhaps don't understand that what you hear in the home is totally determined by the quality of the recording, the speakers, and the acoustic environment. 2 of 3 aren't even part of an audio system, so you are asking a question that demonstrates lack of understanding of the basics of home audio. Again, this can be corrected if you want to correct it. The result would be, as I implied, more accurate and realistic home audio.

The post I referred to used logic and data to support several points that are in opposition to what you say. You can't just dismiss such information with a sneer, you look foolish when you do that.

[WmAx]

Surely you jest. Are you suggesting that Chris' two graphs are conclusive proof that such provides a clear picture of dynamic behavior?

I'm not sure what's being assumed. My post and graphs were not intended to encapsulate 'a clear picture of dynamic behaviour'. They were intended to outline the 'TIM' distortion that was referenced to earlier; nothing else.

Do tell me of an op amp based circuit that is so perfect it's distortion is inaudible in reproducing musical content. This is really going to be quite amusing!

What do you mean? Objective or subjective inaudible distortion? Objectively, their are tons of low cost operational amplifiers available that should have inaudible levels of distortion(IMD and THD) throughout the entire audio bandwidth. Even the cheap NJM4556 I referenced in the 2nd graph, produced no audibly appreciable distortion according to known human threshold studies of THD and IMD[1]. Subjectively, by this I mean sighted A/B listening without controls; of course this is non-determinant solely by measurable parameters. Psychological influence would be a probably contaminent of the test.

[1] Just Detectable Distortion Levels, Jamies Moire, F.I.E.E., Wireless World, February 1981

-Chris

[RobotCzar]

I'm not sure what's being assumed. My post and graphs were not intended to encapsulate 'a clear picture of dynamic behaviour'. They were intended to outline the 'TIM' distortion that was referenced to earlier; nothing else.


-Chris

You stated that multiple THD measurements at high frequencies can be used to judge dynamic distortion, and that TIM is not really a separate "type" of distortion. That claim, is detrimental to e-stat's belief that somehow THD is worthless. Your post also points up the fact that he has no basis to think that TIM typical of opamps (or any other amps) is audible. (Maybe it does effect "subjective distortion" --wink wink.)

Thanks again for your contribution.

E-stat has zero evidence that TIM is audible at levels found in cheap amps or op amps (acutally he has no evidence that TIM is typically lower in expensive descrete amps either). This does not stop him from claiming he is making some kind of point.

[WmAx]

You stated that multiple THD measurements at high frequencies can be used to judge dynamic distortion,

This statement is broad. I did not state that exactly. Dynamic distortion as a term that could concievably apply to almost anything. Specifically, I referred to the dynamic effect/non linearity that occurs in relation to a slew rate that is insufficient for a given frequency vs. voltage and it's result when this is exceeded.

and that TIM is not really a separate "type" of distortion. That claim, is detrimental to e-stat's belief that somehow THD is worthless.

I agree. Of course -- THD is important; but it must be measured under enough conditions and a large enough sample of data points to be useful. For example, that IC-150 pream discussed eariler would likely have good distortion measurements at high frequencies IF you did so at steady state 2 volts and under into a typical load -- but above that voltage(and more then 2 volts average may be required to achieve adequate volume with many amp/speaker combinations - nor does this consider the peak voltage for dynamic parts of the recordings) and the distortion rapidly would have to rapidly increase. I just did not want any confusion. :-)

-Chris

[Sealed]

I see place for sarcasm, definitive nouns(accuratey describing behaviour) or other methods of 'insult' of poking 'fun' at the actual issues at hand if done properly and within the proper scope on a forum. However, what you have done here is to resort to petty name calling that is not based on observable traits of the person you are responding. Or do you have substantiatino he is a boy-raping POS? Why not point out exactly what parts of his demonstrated electronic knowledge is wrong? Or is the extent of your capability limited to weak "I said so" type arguments?


-Chris

Far be it from me, if you two lovers want to get a hotel room, I am not going to stand between you.

[E-Stat]

E-Stat, Ok, I give up trying to reason with you. Obviously neither logic or data are meaningful to you.

Or at least your colored interpretation of that concept. I am a computer programmer by trade and understand logic quite well.

Name plates, however, are--or you would not be asking for name dropping.

If a scientist asks another as to which test instrument one used, is that name dropping? Or trying to understand the point of reference. Hide behind your weak experience.

I tried to imply (perhaps too subtlely) that the only sonic truth is a live performance.

While that is true, it does not in any way negate qualitative differences amongst literally hundreds of audio components. You would understand if your experience were wider.

You may be inexperienced in listening to live music, so you perhaps don't understand that what you hear in the home is totally determined by the quality of the recording, the speakers, and the acoustic environment.

Sorry, your superiority complex doesn't work with me. I attend the ASO regularly, and my long term friend and ex-Absolute Sound reviewer John Cooledge is a member of the syphony board and advisor on their recordings. Consequently I have enjoyed the luxury of company with Robert Shaw, Robert Spano, and a number of musicians from the symphony. You will find my name in a minor role in the Telarc recording of ASO's Firebird. My wife regularly plays the baby grand in the living room. Your comments suggest that you must be part of the dense "all amplifiers sound the same camp". Sorry to hear that! While the acoustic venue is a critical component, it is not the sole one.

The result would be, as I implied, more accurate and realistic home audio.

I have a number of very nice minimally miked recordings of unamplified music. At HP's, I have sampled a boat load more of exceptional recordings, some of which are not available to the public. As for speakers, I use full range electrostatic speakers that resolve instruments quite well, thank you.

The post I referred to used logic and data to support several points that are in opposition to what you say. You can't just dismiss such information with a sneer, you look foolish when you do that.

No it doesn't. It uses a simplistic example and theory to explain a complex system. You let your guard down in another post by talking about your AR98s. Fine bookshelf speakers. I have a pair of Large Advents in the garage myself. I trust, however, that they are not your reference point as to what audio speakers are capable of doing. If so, you really have no idea what is possible.

rw

[E-Stat]

My post and graphs were not intended to encapsulate 'a clear picture of dynamic behaviour'. They were intended to outline the 'TIM' distortion that was referenced to earlier; nothing else.

Indeed. I understood your point, but the Robot read far more into your comments that you intended.

What do you mean? Objective or subjective inaudible distortion?

Well for starters, the distortion is most certainly audible when playing musical content.( I couldn't care less what happens with simplistic tones) .The ability to tell the difference between using an op amp based amplification stage versus using none at all. A bypass test. I am fortune in having a high output CDP with low output impedance and use short, low capacitance cables (4 volts/75 ohms/80 pF). That allows me to choose to either use my Audio Research SP-9 MKIII preamp in the circuit or to not at all. In it's place, I use a DIY attenuator using DACT and Cardas components. The audible difference between using a good preamp and none is clear: It is far from perfect and loses detail and shrinks soundstage. Tell me of a commerically available preamp using op amps that is capable of being completely transparent so that its presence cannot be discerned from its absence. I've yet to hear ANY preamp of any design meet that criteria.

rw

[RobotCzar]

"Or at least your colored interpretation of that concept. I am a computer programmer by trade and understand logic quite well."

Well, actually, no you don't. I have asked you if the harmonic structiure of distortion makes a difference is the total distortion is inaudible and you either can't or won't answer. Indications are that you don't understand the logic involved. (By the way, I have an M.S. in Computer Science, I am a licensed teacher of physics, and I am a PHD student in educational psychology. I find your comments illogical and without proper understanding of the basics.)

"If a scientist asks another as to which test instrument one used, is that name dropping? Or trying to understand the point of reference. Hide behind your weak experience."

Obviously scientists can and do merely state the performance characteristics of their equipment. Brand names would not be used unless they unambigiously specific the performance parameters of the instrument. Are you making thiis stuff up? Your statement indicates a poor logical understanding of scientific procedure. You also seem to be confused about the fact that home audio amps are not scientific instruments--even your tweako expensive ones.


"While that is true, it does not in any way negate qualitative differences amongst literally hundreds of audio components. You would understand if your experience were wider."

Actually, I would "understand" if my experience were narrower. like yours. If my points don't negate qualitative differences among amps (not all components) then why not tell me how I am wrong? You are wrong as there is no evidence of audible differences, got that?--zero evidence to back up your pet belief.

"Sorry, your superiority complex doesn't work with me. I attend the ASO ... suggest that you must be part of the dense "all amplifiers sound the same camp". Sorry to hear that! While the acoustic venue is a critical component, it is not the sole one.

Then why are you asking about truth is systems, why aren't you getting that only live performance is the "truth"? Why did you only ask about my components and not my listening room and its arrageemnt?


"No it doesn't. It uses a simplistic example and theory to explain a complex system. You let your guard down in another post by talking about your AR98s. Fine bookshelf speakers. I have a pair of Large Advents in the garage myself. I trust, however, that they are not your reference point as to what audio speakers are capable of doing. If so, you really have no idea what is possible."

You keep spouting mumbo jumbo and don't make any logical sense. I am trying to keep things simplistic because you don't seem to be getting the basics. "simplistic" Audio reproduction is simple in regard to electronics, it is the acoustic and psycho-acoustic factors that are complex. Electrical behavior at the level of home audio is completely understood by scientists and electrical engineers, not cult magazine editors. Why don't you explain how and why my point are wrong instead of ignoring them or just labling them

Let me review a few:

1. You claim measurements of THD are useless, when I ask you for what isn't you mention TIM (a form of dynamic disortion) but I contend (and Chris provided some support) that TIM IS INCULDED IN THD measurments. This is a fact, I will give you references if you like. If TIM matters, and it is included in THD, then how can THD not matter? You didn't know this, admit it.

2. You mention the haromonic structure (odd vs even) of distortion. But, when I ask if it matters if the total is below audiblity you say that is too simplistic. Well, why not clue us in as to why that is too simplistic? It seems a logical as the nose on your face. Can't you logically support your beliefs?

3. I have mentioned that recording quality and room characteristics have a great effect on what you hear. But, you are only interested in the brand names of my equipment. Do you think that the listening room has no effect? If you think it does, then you can't know about my system unless you hear it in its present location. I say your assumptions are all wrong, you are focusing on electronics and they clearly have the least effect on what we hear from recordings. How can your comments be taken seriously given this error?

Respond logically to these issues or be dismissed as a lightweight.

[E-Stat]

Well, actually, no you don't. I have asked you if the harmonic structiure of distortion makes a difference is the total distortion is inaudible and you either can't or won't answer.

Let me 'splain it to you again. Take it reaalll slow so you get it. AVERAGING distortion over time is not the same as measuring instantaneous distortion. It really shouldn't be a difficult concept for you to grasp. The results are audible.

(By the way, I have an M.S. in Computer Science, I am a licensed teacher of physics, and I am a PhD student in educational psychology. )

Congratulations. Do you prefer reading graphs to listening to music?

If my points don't negate qualitative differences among amps (not all components) then why not tell me how I am wrong?

You seem to live in a world of theory devoid of exposure to what can be achieved today. Do show me these wonderful studies using gear beyond mid-fi. I'm all ears.

Then why are you asking about truth is systems, why aren't you getting that only live performance is the "truth"? Why did you only ask about my components and not my listening room and its arrageemnt?

For a PHD, you really need to work on your reading retention. I asked for your audio reference IT DOES NOT HAVE TO BE YOUR OWN

Comprende? Do you get it?

You have actually raised a very good point concerning the room. Please do elaborate. Or are you insecure about that as well?

Why don't you explain how and why my point are wrong instead of ignoring them or just labling them

You would understand if you used experience and not theory as your basis. I am far more interested in applied knowledge.

1. You claim measurements of THD are useless, when I ask you for what isn't you mention TIM (a form of dynamic disortion) but I contend (and Chris provided some support) that TIM IS INCULDED IN THD measurments. This is a fact, I will give you references if you like. If TIM matters, and it is included in THD, then how can THD not matter? You didn't know this, admit it.

His claim is that today, unlike the timeline of the specific and dreadful product I mentioned, such measurements can be made. Perhaps Crown could not make the same claim today. I will ask you again to mention a preamp or power amp that you ascribe to having inaudible distortion. I await your applying theory to a tangible product.

2. You mention the haromonic structure (odd vs even) of distortion. But, when I ask if it matters if the total is below audiblity you say that is too simplistic. Well, why not clue us in as to why that is too simplistic? It seems a logical as the nose on your face. Can't you logically support your beliefs?

Your suggestion is absurd because you assume the conclusion first. Harsh upper harmonic distortion components can be audible in sufficient quantities. Evidently, you have not listened to many first generation SS designs.

3. I have mentioned that recording quality and room characteristics have a great effect on what you hear. But, you are only interested in the brand names of my equipment. Do you think that the listening room has no effect? If you think it does, then you can't know about my system unless you hear it in its present location. I say your assumptions are all wrong, you are focusing on electronics and they clearly have the least effect on what we hear from recordings. How can your comments be taken seriously given this error?

Did you read my last post? Or is it that lack of comprehension thing again? Of course recordings make a difference. Of course rooms make a difference. Are they the only factors? Of course NOT. Are you really unable to hear differences among amplifiers? Sorry to hear that.

Respond logically to these issues or be dismissed as a lightweight.

Done. Still hiding behind your cloak?

rw

[WmAx]

Well for starters, the distortion is most certainly audible when playing musical content.( I couldn't care less what happens with simplistic tones) .

I'm afraid I lost you. Distortion is 'most certainly audible when playing musical content' on what specifically? This sounds like you performed a test of some specific product. Which product? What test conditions/methdology? Was teh device thoroughly measured/analyzed to observe levels of non linearity?

That allows me to choose to either use my Audio Research SP-9 MKIII preamp in the circuit or to not at all.

Is this the preamp you referring to in the preceding statement?

The audible difference between using a good preamp and none is clear:

What testing methodology? Measurements taken to find non linearities that may be audible?

Tell me of a commerically available preamp using op amps that is capable of being completely transparent so that its presence cannot be discerned from its absence.

At the immediate moment, I'm not aware of any dedicated preamps that use op-amps as the gain stage. However, I believe some are manufactured. I can not at the immediate moment refer to any, nor do I have access to detailed measurment analysis of these preamps. However, theoretically, you could use the vunerable NJM4556 to make an audibly transparent preamp according to known human thresholds of distortions.

-Chris