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Op Amp Rolling

SIY

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beefkabob

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I know what I’m hearing. You’re wrong.
Show me measurements that there's an actual, perceivable difference in sound, or show me the statistically real blind testing results. It's all a placebo. Psycho-acoustics are real. Actual sound differences in opamp rolling? Nah, only if something is broken or incompatible. Fosi has been known to make broken equipment, though.
 

Doodski

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@olds1959special. I can't read through all 6 pages of this thread at this time so can you give me a bullet point detailed short form explanation of what you hear that is better versus what is worse<?>
 

olieb

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Yea, but the sound of the op amp when playing music is worse to my ears.
Worse than what?
Worse than the Muses, that whistled so nicely? You liked the tune?
 

Mnyb

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I guess you just can’t hear the differences, or you wouldn’t be asking to see measurements.
Living under a bridge much ?

it’s because you claims that you can hear differences where they should be none . Some folks here would rather see some proof .
 

Emulator II

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I know what I’m hearing. You’re wrong. I know I’m right, because I can clearly hear the difference. Not everything affects the sound, power cables don’t, and USB isolators have not made a difference. But op-amps do.
So I think you should try the Sparkos. From what you can read, they were designed specifically for people who can hear the difference. Plus they look cute.
 

DVDdoug

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I know what I’m hearing. You’re wrong. I know I’m right, because I can clearly hear the difference.

Sighted tests "don't count". ;)

What is a blind ABX test?
But, the only practical way to do that if you don't have a spare identical unit would be to put one op-amp on the left and another on the right, and do a mono listening test with someone else doing the (blind) connection-switching.

And they especially don't count if you can't identify or describe the difference which would be background noise, distortion, or frequency response. Those are (almost) the ONLY "sound quality" characteristics, despite all of the meaningless words that "audiophiles" use. I'd be more inclined to believe there's really a difference if you said, there's a buzz, or the left channel is quieter, or there's no bass, or something else definable and "scientific".

So if one of them makes a noise on start-up, yes I believe that. And if it has that defect, it may have other audible defects in the noise, distortion, or frequency response.

See Audiophoolery for the characteristics that actually affect sound.
 

beefkabob

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Sighted tests "don't count". ;)

What is a blind ABX test?
But, the only practical way to do that if you don't have a spare identical unit would be to put one op-amp on the left and another on the right, and do a mono listening test with someone else doing the (blind) connection-switching.

And they especially don't count if you can't identify or describe the difference which would be background noise, distortion, or frequency response. Those are (almost) the ONLY "sound quality" characteristics, despite all of the meaningless words that "audiophiles" use. I'd be more inclined to believe there's really a difference if you said, there's a buzz, or the left channel is quieter, or there's no bass, or something else definable and "scientific".

See Audiophoolery for the characteristics that actually affect sound.
He can't ABX it. That would require swapping op amps. He'd have to buy two dacs then, and maybe a hardware switcher. There's literally no way to prove things other than measuring.
 

beefkabob

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1. NE5532 sounds less detailed, like the sound has a veil.

2. MUSE02 sounds more detailed with more openness and space in the sound, with a little less bass presence.
And Santa Claus is real. Give us some measurements., or go to another forum if you're not hear to learn. Amirm recently reviewed a great ADC for measuring. You could then prove that you're right. Or you could prove that you're wrong. Either way, the results would be satisfying.
 

olieb

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It only made the sound on startup.
Maybe, but as these opamps were oscillating, there could be weird things going on (distortion) even after the startup whistle stopped, as the amp is still very close to oscillating or the oscillation is just in the ultrasound range. Without measurement nobody knows.
And maybe you like this distortion. Or it is just (sighted) bias, which is the most probable thing.
 
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Mnyb

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He can't ABX it. That would require swapping op amps. He'd have to buy two dacs then, and maybe a hardware switcher. There's literally no way to prove things other than measuring.
+1

and you should have measurement equipment when endeavour to redesign someone else’s circuit and also understand that circuit .
how else to verify that everything works as expected ? It’s about design hygiene not always sound quality a lot of things can and will go wrong ?
 

Doodski

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He can't ABX it. That would require swapping op amps. He'd have to buy two dacs then, and maybe a hardware switcher. There's literally no way to prove things other than measuring.
Measuring and relating that to real world experience can be done but it is a remote chance.
 

Doodski

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Op-amps affect the sound. If you can’t hear the difference, have you gotten a hearing test lately? Maybe you are just deaf? I have built a headphone amp and experimented with different op amps and could clearly hear differences. Measurements can confirm what may already be heard.
Send in what you have for test review and let's check it all out.
 

LTig

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He can't ABX it. That would require swapping op amps. He'd have to buy two dacs then, and maybe a hardware switcher. There's literally no way to prove things other than measuring.
He could ask someone else to replace the opamp by chance while he is away, maybe once per day for 10 days. Then compare what he prefers with the list which opamp was inside.
 

LTig

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I guess I could. Here's some pics of it. There's no volume control, and it's powered by an external PSU. I put in the op-amp socket so I could roll the op-amps.
You use a dual opamp to drive headphones? No wonder they sound different as almost all are used outside their specification.
 

Mnyb

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I guess I could. Here's some pics of it. It doesn't sound amazing compared to commercial stuff, but it works. There's no volume control, and it's powered by an external PSU. I put in the op-amp socket so I could roll the op-amps.
You drive headphones directly with the op ? Some might do it ok but not all of them, and it says nothing about how it would fare in another circuit . Application is everything use the rigth tool for the work ?
 

olieb

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Op-amps affect the sound. If you can’t hear the difference, have you gotten a hearing test lately? Maybe you are just deaf? I have built a headphone amp and experimented with different op amps and could clearly hear differences. Measurements can confirm what may already be heard.
It's really nice to see people in the know come on here from time to time, show off their broken design (e.g. oscillating amps, opamps driving low impedance, etc.), make bold claims about audibility, but have nothing to show for it except anecdotal experiences that look exactly like storybook examples of sighted bias at work. Even if these people do not act so nicely ("Maybe you are just deaf?")
Without their experiences, we really wouldn't know anything.
I did read about broken designs being audibly different compared to competent ones here on ASR though.
 

Mnyb

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https://en.wikipedia.org/wiki/CMoy

I remember I had good results with a few op-amps like OPA2132PA, OPA2134, OPA2107
Yes the article cautions against using just any OP amp . Check the specs before trying .
and what headphones ? Check their impedance spec too ?

there are limits to this design. If you against any of those it’s not really the proper use of that op .
 
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