opamps THD+N/IMD/SNR measurements don't mean jack IRL, so let it go humm'kay?  

Oh yah, I forgot those measurements: http://audio.an-pan-man.com/files/rmaa/earth_vs_moon_vs_sunv2_vs_lt1469.htm

There are some rather more extensive measurements on two of the Audio-GD opamps at http://www.sg-acoustics.ch/analogue_audio/ic_opamps/index.html

The picture is rather less flattering - so much for design it by ear

Oh yah, I forgot those measurements: http://audio.an-pan-man.com/files/rmaa/earth_vs_moon_vs_sunv2_vs_lt1469.htm

If the 3 discrete A-GD opamps sound the same, then I'm the new king of England. I shall claim my throne very soon.
 

Ignoring the issues with RMAA, those RMAA measurements are so close to each other that I'll bet all 3 sound the same. Have you ever heard the difference between -95.4dBr and -93.8dBr? I can't. I'm not sure what you're trying to prove by showing those measurements unless you're starting from your conclusion.

Yep, I definitely don't enjoy listening to music from the 80's. The best sounding music to my ears is from the 70's and yes it did go through valve equipment.
 

No, no. Even professional audio equipment goes through 5532s today. Hell, a lot of professional audio equipment still uses a 4558 op amp. I think you overrate the op-amps that are used in professional lines of work. 

Well, all opamps sound different in many ppl's experience. And yes, I can easily identify the nasty SQ of 5532 for instance. When you own so-called "transparent" source equipment, you're basically listening to the opamps that your music material was forced to get through.

I honestly wouldn't know 

Last time a member of Team ThreadCrap(now banned) tried to make a point that all DAC's sounded the same(to him at least), I passed his test: http://www.head-fi.org/t/502889/so-who-can-abx-this-recording-from-the-source

Since these are both tied into the same I'll address them both. First off, that test is not a good test of DACs or op amps -- it's simultaneously a test of ADC technology. I don't know ADC technology as well, but I do know that much more care is put into ADC technology rather than DAC technology in the professional field. If you think about it logically, this makes sense -- the actual playback is less important in the studio, rather then the actual recording. There's a lot more care in that area. The DAC portion takes a complete backseat to the rest of the technology. 

As for that test specifically, look at all of the factors that are being tested here: 

1. It's an Essence STX, an internal sound card. This makes it partially a test of the electrical grounding of the original poster's computers

2. It's a test of the Essence STX's ADC, which is a far worse component than its DAC.

3. It's a test of ths Essence STX's DAC and amp.

4. It's a test of your DAC and amp.

5. He even got the levels matched wrong.

All of these factors are in the chain and, in all honesty, makes it not a test worthwhile.

How could he honestly believe that 5532's and 4562's wouldn't color the sound?

Well, all that matters is whether it sounds good to *YOUR* ears...we all know that buying equipment based on cyber-hearsay does not work. My point is that manufacturers throwing killer opamp based measurements as if it were the be-all/end all of audiophilism is the real con. Know your enemy.

And what's "objective" about measurements that were compensated by a feedback system again? I don't think you got the memo.

Oh well, I guess could dig for hours through google and show why feedback is evil and allows to cheat for killer measurements. Maybe even A-GD has a section on why he calls all his newest DAC's "No Feedback".

Who actually uses RMAA to prove these points? You're beating on a strawman here.

Hey guys, so many threads end up closed due to Team ThreadCrap whose members always feel like showing biased measurements and explaining to the world that their $90 amp sounds exactly the same as any $3K amp, meaning that anything costing more than $90 is audiophool snake oil yada yada...they also honestly seem to believe that their duty is to the save the humanity from being robbed.

So I thought it was time to finally put an end to all this, and I've got clues this time

A design engineer who's a discrete believer recently told me:

Couldn't have said it better, yes 5532 is the RMAA pimp daddy yet it does sound like ####.

I will admit, as someone who is not a sound engineer, I won't comment on the feedback circuit. What I will say is still that RMAA is not the end-all for metrics and I still don't see many people use it on the Sound Science forum.

http://www.diyaudio.com/forums/everything-else/88894-discrete-components-better-than-opamps.html

Nice job not showing the other part of that post.

Your quoted portion talks purely about the powering aspect of op amps versus transformers -- this is more important for speaker amplifiers, like a class A power amplifier. Discrete components would be preferred for making power amps due to the higher amount of power and current required. Speakers, with their lower impedances, require more current and naturally gravitate away from op amps, but often times struggle with ever-increasing current. Even the high end OPA627 caps out at +- 18V. That's nowhere close to the power that some speakers can pull from a powered amp. 

That's what this post is saying op amps come up short. This has nothing to do with the actual sound output, this has to do with the power output and where op amps should be used.

http://www.gearslutz.com/board/4432704-post5.html

You're pulling a post out of context again. The poster in question posted a study to back up his findings later in the topic, but that study really didn't say anything to back up what he saying. The study was a test to see if non-linear distortion would make music less tolerable for people to hear.  Of the 21 stimuli, only one them averaged above "imperceptible" by the subjects, and it was only 0.18 points above the imperceptive rating. Regardless, this says nothing about op amps, this is all about putting non-linear distortion into music and whether or not it has a perceptible difference. Overall, it was a paper that was suggesting that this Geelee measurement be used for measuring distortion levels, rather than THD+N% and IMD, because it takes linearity of the distortion into account. All it is saying is that distortion at different places is more annoying than a linear amount of distortion. 

and I see that the latest Sabre DAC chips carry built-in opamps now, so every manufacturer will throw killer THD+N measurements at 'cha as if they meant anything useful at all.

In many cases this is true -- pretty much every well designed circuit has distortion low enough to not matter. 

If Audio-GD decided to call all their latest DAC's "No Feedback", there's a good reason to it

So feedback is evil, and opamps measurements don't mean jack. Thanks for passing by.

Oh yah, I forgot those measurements: http://audio.an-pan-man.com/files/rmaa/earth_vs_moon_vs_sunv2_vs_lt1469.htm

If the 3 discrete A-GD opamps sound the same, then I'm the new king of England. I shall claim my throne very soon.

Rmaa results are like no results, disregarded.
 

Yep, I definitely don't enjoy listening to music from the 80's. The best sounding music to my ears is from the 70's and yes it did go through valve equipment.

Something I partially agree with, valve amps tend to do better on studio recording(not playback) according a certain AES paper. http://milbert.com/articles/tubes_vs_transistors

Well, all opamps sound different in many ppl's experience. And yes, I can easily identify the nasty SQ of 5532 for instance. When you own so-called "transparent" source equipment, you're basically listening to the opamps that your music material was forced to get through.

Optimum implementation of 5532s will get you better results.  

I honestly wouldn't know

Last time a member of Team ThreadCrap(now banned) tried to make a point that all DAC's sounded the same(to him at least), I passed his test: http://www.head-fi.org/t/502889/so-who-can-abx-this-recording-from-the-source

How could he honestly believe that 5532's and 4562's wouldn't color the sound?

Maybe we should try such a test with the Benchmark line of converters, that would be interesting as a prove of concept on the 5532's color.

Well, all that matters is whether it sounds good to *YOUR* ears...we all know that buying equipment based on cyber-hearsay does not work. My point is that manufacturers throwing killer opamp based measurements as if it were the be-all/end all of audiophilism is the real con. Know your enemy.

And what's "objective" about measurements that were compensated by a feedback system again? I don't think you got the memo.

No offence to the DIY community or anyone but I would rather trust Audio Precision, DScope and the knowledgeable guys from Sennheiser and other manufacturers who are using their(audio precision) products for their reference.

Oh well, I guess could dig for hours through google and show why feedback is evil and allows to cheat for killer measurements. Maybe even A-GD has a section on why he calls all his newest DAC's "No Feedback".

I can do the same for digging up papers to show why some measurements are important in audio.  

Snip...

I don't think you have read what I wrote in the OP, and I also presume that you have never heard those 3 discrete opamps(I have). There's an implied rule on head-fi that ppl shouldn't talk about gear they haven't heard for themselves. Earth, Moon and SunV2 sound all extremely different from one another....they measure pretty much identically, oh yes they do...big deal when their feedback system cons your meter

This is the Sound Science forum, my friend. I'm afraid this doesn't help me any. You're right, though, I don't go out DIY op amp rolling. You're using a logical fallacy, though, you're starting from your conclusion to make your point. By assuming that they sound different and asserting only your word, you suggest the measurements are flawed, rather than showing something to back up why they sound different. All I did was interpret the measurements in front of me, which are RMAA and can't be trusted to start. As I said in my last post, and you ignored, RMAA has issues and I pretty much never see anyone use them in actual arguments on the Sound Science forum. Every time you bring RMAA up or the flaws with a feedback system, you're attacking a strawman. 

Oops, I should have made clear that I hardly ever listen to >1979 music, coz the SQ is hardly ever up to my personal standards. I'm well aware that pro audio gear runs the crappiest opamps ever...like those snake oil RME/Lynx über-pricey internal soundcards that newbie audiophiles like to call the top of the crop. All they have for them is good clocking, but they use a stellar ripple and very noisy shared ATX PSU and crappy 5532/2068/4580 opamps. They justify their prices by running excellent drivers, but clearly you're not paying for audiophile grade hardware.

Where did sound cards into the mix? You just side-stepped the issue of the music already running through the op-amps by moving onto a tangent about electrical grounding with internal sound cards. I don't see the relevance of the 1979 comment -- professional audio equipment still uses those "crappiest op amps." I don't understand how this deflects any of the points.

The STX is using a bunch of 5532's on its line-in, it also measures amazingly well in both AP and RMAA. It's the perfect example of this opamp feedback bs that falsifies measurements and allows companies to sell shrill sounding gear on the promises of inaudible distortion.

It's only a line-out>line-in loopback on the STX, which carries some of the killerest measurements you can find...it's all inaudible, remember? So how come the drums sound flat and boring on the loopback? 5532's at work my good friend.

You're ignoring the rest of the points I made there. I'm saying you can't localize the issue to the op amp. You yourself brought up the issue of electrical grounding, which I agreed with. 

Indeed, because all opamps measure the same...it would very much appear that the only way to know how a piece of equipment based on opamps sounds is to listen to it with your own ears. Their feedback system falsifies measurements for the best and turns any shrill sounding shiny box into a measurements fairy tale.

What? You pulled that statement out of context! I was saying your proof for op amps sounding differently was a post on power, not on the sound quality! You twisted that into some kind of argument about feedback systems and measurements. All I was saying was that the post argued that transformers are better for high power usage and are used on powered amps, a point which I agree on, and was saying how op amps were not suitable for that work.