Can you hear a difference between OPA2134 and LME49720 in the PRE-TC10?

[DaneelOlivaw]

Very interesting initial pattern.
01/01
02/02
03/03
03/04

... exactly the same as mine ...

I was pretty sure I could hear the difference ... especially the initial clapping (more air in one track) ... and one had sharper "ess" in the female vocal ...
For me, I donno if fatigue/boredom set in after that, it just went downhill after 4-5 tracks for me.

Question for you ... after the initial 3-4 tracks ... did boredom/fatigue set in for you? Or you were all ok to the end of the test? I'm just curious ...

I did now my first steps with ABX plugin. I tried with the "Fast Car" sample which i was not able to hear differences before. But with ABX
I think I heard that the Hi Hats sounded slightly different right at the beginning.
The longer i tested the more it sounded quite similar to me.
It was not better or more detail but like you turn your speakers silghtly to a side. Maybe a delta check only from the hiss sound in this fraction of a second might be interesting.

And using ABX you should have a break each time after 4 comparisons.

Default : Lautsprecher (SABAJ USB DAC) [exclusive], 32-bit
Crossfading: NO

12:39:22 : Test started.
12:39:37 : Test restarted.
12:39:37 : 01/01
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12:39:53 : 03/03
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12:41:38 : Test restarted.
12:41:38 : 06/08
12:41:38 : Test finished.

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Total: 6/8
p-value: 0.1445 (14.45%)

-- signature --
d6190de6b1a46df10e781f31c763d3aeccf91beb

 

[solderdude]

Try:

4 attempts .... pause for an hour or so ... do another 4 attempts ... then pause again before doing the final 4 attempts.
Maybe this would be a way for you to ace this test if it is a question of listening fatigue.

But I rolled a dice 8 times in a row and wrote down if it was odd or even.
Did this 4 times.

Overall (32 throws) yielded 19 odd and 13 even and these were thrown dice.

Notice how there were 2 times this was 6 odds out of 8 and the 2nd and 4th attempt (much to my surprise) were 4 odds in a row.
Now suppose the 'odds' were 'correct identification' then the 4 'corrects' in a row could also be chance.

This is why I recommend 20 attempts or so (maybe in your case 5x a 4-switch attempt).
My experience is that unless the differences are quite audible after a few switches doubt kicks in and may or may not skew the results.
It is safe to say that differences in op-amp performance are negligible and would be impossible to prove with 20 attempts in one go.
8 or 10 attempts may not be conclusive unless one repeats it the following day or so.

Such is the difficulty with blind tests and stopping while one is ahead...

 

[DaneelOlivaw]

Try:

4 attempts .... pause for an hour or so ... do another 4 attempts ... then pause again before doing the final 4 attempts.
Maybe this would be a way for you to ace this test if it is a question of listening fatigue.

But I rolled a dice 8 times in a row and wrote down if it was odd or even.
Did this 4 times.

View attachment 443137

Overall (32 throws) yielded 19 odd and 13 even and these were thrown dice.

Notice how there were 2 times this was 6 odds out of 8 and the 2nd and 4th attempt (much to my surprise) were 4 odds in a row.
Now suppose the 'odds' were 'correct identification' then the 4 'corrects' in a row could also be chance.

This is why I recommend 20 attempts or so (maybe in your case 5x a 4-switch attempt).
My experience is that unless the differences are quite audible after a few switches doubt kicks in and may or may not skew the results.
It is safe to say that differences in op-amp performance are negligible and would be impossible to prove with 20 attempts in one go.
8 or 10 attempts may not be conclusive unless one repeats it the following day or so.

Such is the difficulty with blind tests and stopping while one is ahead...

You are right 8 are not enough for evidence. Especially if i had only 6 hits. And to repeat next day allows cheating because you can select a good series and dont show the bad. Only in one bigger test you have the proof with the signature.
I think 10-12 will be sufficient if you have 100% hits. This will be 1 to 1000 or 4000. 1 to 1000000 is overkill from my point of view.
In my test i was pretty shure the first 4 times and then from 5 (which was right) i was guessing. A good test will take time. I play bass in a Band and i have to synchronize with my drummer. My old and tortued ears are not so good but im very sensitive hearing small ticks on the high hat. And in heavy guitar attacks its important to hear wether the sound is really from the drummer. And so i realize, that this instrument doesnt sounds natural for me in "Fast Car".

P.S.: my english is not so good. Maybe "high hat" is not the right word for the Cymbal? at the beginning this (tschiktschickytschik) in Track 1 it is a bit brighter.

 

[Bland_username42069]

It’s always a trade off between dynamic slam vs rhythmic punch vs number of veils lifted.

I find that a Benz micro glider cartridge works better with the Opa2134 in the chain but dynavectors prefer a LME.

I will often change op amps between tracks to compensate for different mastering engineers.

Only Ken Shindo separates can do all 3.

 

[w277]

Thank you for the test, PMA!

For what it's worth:

Hardware:
Win 11 PC // Topping D70 pro // Audiophonics HPA-DM500NIL (Hypex Nilai) // Piega Smart 3


foo_abx 2.2.1 report
foobar2000 v2.24.1
2025-04-10 18:01:29

File A: 2134.wav
SHA1: be3c81c4a4dd185262c511bcb0447d7f8c6da138
File B: 49720.wav
SHA1: ec38050c91e3d36050a8a4d580c51324ca3beb4f

Output:
WASAPI (event) : Lautsprecher (TOPPING USB DAC), 24-bit
Crossfading: NO

18:01:29 : Test started.
18:02:50 : Test restarted.
18:02:50 : 01/01
18:03:07 : Test restarted.
18:03:07 : 02/02
18:04:42 : Test restarted.
18:04:42 : 03/03
18:04:54 : Test restarted.
18:04:54 : 04/04
18:05:06 : Test restarted.
18:05:06 : 05/05
18:05:20 : Test restarted.
18:05:20 : 05/06
18:05:43 : Test restarted.
18:05:43 : 06/07
18:06:07 : Test restarted.
18:06:07 : 07/08
18:06:07 : Test finished.

----------
Total: 7/8
p-value: 0.0352 (3.52%)

-- signature --
c5d3688124177cca196ee13cddd1d8ff19f0bc72

 

[boxerfan88]

^^^ ooo you actually can tell the difference!

 

[Ropeburn]

Good job PMA. I don't hear any difference. By the way, are you supposed to hear any difference? In that case, I blame my results on my substandard HiFi.
If the outcome is instead meant to show no audible difference, then I have superb HiFi instead.
(I actually have ok/mediocre HiFi)

Did you just go "your system just isn't resolving enough" on yourself?

 

[DaneelOlivaw]

Thank you for the test, PMA!

For what it's worth:

Hardware:
Win 11 PC // Topping D70 pro // Audiophonics HPA-DM500NIL (Hypex Nilai) // Piega Smart 3


foo_abx 2.2.1 report
foobar2000 v2.24.1
2025-04-10 18:01:29

File A: 2134.wav
SHA1: be3c81c4a4dd185262c511bcb0447d7f8c6da138
File B: 49720.wav
SHA1: ec38050c91e3d36050a8a4d580c51324ca3beb4f

Output:
WASAPI (event) : Lautsprecher (TOPPING USB DAC), 24-bit
Crossfading: NO

18:01:29 : Test started.
18:02:50 : Test restarted.
18:02:50 : 01/01
18:03:07 : Test restarted.
18:03:07 : 02/02
18:04:42 : Test restarted.
18:04:42 : 03/03
18:04:54 : Test restarted.
18:04:54 : 04/04
18:05:06 : Test restarted.
18:05:06 : 05/05
18:05:20 : Test restarted.
18:05:20 : 05/06
18:05:43 : Test restarted.
18:05:43 : 06/07
18:06:07 : Test restarted.
18:06:07 : 07/08
18:06:07 : Test finished.

----------
Total: 7/8
p-value: 0.0352 (3.52%)

-- signature --
c5d3688124177cca196ee13cddd1d8ff19f0bc72

Even if 16 tests were all guessed correctly, it would not be proof that the opamp makes the difference or that one is better. You would need a control recording, where you don't know which opamp it was. It could also be that the difference between two recordings of the same opamp could be heard in the same way

 

[DanielT]

Did you just go "your system just isn't resolving enough" on yourself?

It was just ironic waffle on my part.

But okay, if we're talking about listening and detecting differences with material, music where is theoretically the possibility of doing that, it should be easier to do that with top notch speakers vs. with really crappy speakers.

Training in distortion sniffing is also a factor that I believe is of great importance that can explain individual differences.

 

[w277]

Even if 16 tests were all guessed correctly, it would not be proof that the opamp makes the difference or that one is better. You would need a control recording, where you don't know which opamp it was. It could also be that the difference between two recordings of the same opamp could be heard in the same way

I can't exclude other reasons (than the opamps) for the difference detected. Please note, that I don't know anything about these two opamps.

I compared two wav files, and didn't provide any interpretation of the results.

 

[boxerfan88]

Kinda interesting ... in the other opamp measurement thread, the conclusion was, no audible difference.

I undertook the ABX test, and I failed (ie. could not hear a difference). There are some people who undertook the ABX test and the result show that they can hear a difference; which I find interesting.

What this tells me is that there are some folks who can and do hear a difference, validated by ABX test, therefore casting a little doubt about the no audible difference conclusion.

And then I see post saying the ABX test isn't valid coz the recording was not "controlled". Ha ha ....

 

[Sokel]

You would need a control recording, where you don't know which opamp it was.

???
That's exactly what this test is, you have no way of knowing with foobar's ABX test, that's its whole point.

 

[pma]

???
That's exactly what this test is, you have no way of knowing with foobar's ABX text, that's its whole point.

Sure! Sometimes I am perplexed of comments of some members. But it makes not much sense to correct them, one might have been night and day here and that would not be effective way of spending my time.

 

[restorer-john]

On the other hand, Tracy Chapman’s Fast Car gives me no potentially audible differences. I do not know why this track is used for ABX tests. Maybe it is fine for speaker testing (though I doubt it) but definitely not for the tiny op-amp differences.

It was just a track played to death in the late 80s, the glory years of CD and HiFi demos. Most of the people still playing it in 2025 are just yearning for that time when they had more hair and more girls hanging off their arms.

Same thing for Jennifer Warnes Bird on a Wire off the Famous Blue Raincoat CD. It was played to death too and it wasn't that well recorded either. HiFi stores and audio shows have a lot to answer for.

 

[pma]

Yeah. And Toole/Olive recommended the Fast Track, that might be a reason as well.

 

[thewas]

The reason that Fast Car was used by the Harman research as due to its wide and smooth spectrum it seemed to be most revealing for tonal problems after pink noise:

Dr. Sean Olive on 35 Years of “Fast Car”

https://www.soundstageaccess.com/index.php/feature-articles/1259-dr-sean-olive-on-35-years-of-fast-car

www.audiosciencereview.com

 

[pma]

I know. With speakers, maybe. For this kind of music.

 

[KSTR]

In my book, "Fast Car" is close to useless for audio quality assessment. It has no bass, no treble, limited transients, little dynamics, sparse spectrum, limited sound stage and Tracy's voice has this unique and rather unusual natural timbre that stands in the way of judging if it sounds tonally colored or not. To me, the track basically always sound good, even on junk equipment just by the way it is designed.

 

[restorer-john]

The reason that Fast Car was used by the Harman research as due to its wide and smooth spectrum it seemed to be most revealing for tonal problems after pink noise

After 35 years of that track, anyone would prefer pink noise...

Seriously, it was a popular debut album with some catchy hits and reasonably well recorded. It's nothing special otherwise and certainly not "the most revealing for tonal problems". Did anyone seriously say that?

In 1988/9 when they started playing it to death, there were many hundreds of better recorded, more detailed and balanced popular recordings available.

 

[restorer-john]

In my book, "Fast Car" is close to useless for audio quality assessment. It has no bass, no treble, limited transients, little dynamics, sparse spectrum, limited sound stage and Tracy's voice has this unique and rather unusual natural timbre that stands in the way of judging if it sounds tonally colored or not. To me, the track basically always sound good, even on junk equipment just by the way it is designed.

Exactly correct. It's probably part of the problem why the so-called Harman curve is shaped the way it is- compensating.

Just a consistent reference track, that's all, and not a good one at that. It certainly wasn't a track I ever used to highlight differences in loudspeakers or other gear when comparing and selling HiFi to actual customers in the early 1990s. I bought the CD of course, but tired of it and so had everyone else.