Does Op-amp Rolling Work?

[pma]

OPA's origin?
Put in an adapter with nice long pins I guess.

Schematic?

Layout.

 

[cgallery]

OPA's origin?
Put in an adapter with nice long pins I guess.

Schematic?

Digikey. No adapters.

 

[cgallery]

Layout.

The A07 amplifier.

Before any of you get too worked up, I'm just indicating I thought I heard a difference but it could be down to a misbehaving/noisy 4562.

 

[Sokel]

Digikey. No adapters.

Digikey= original, check.
No adapters= no extra distance from caps and resistors, check.

It's only down to proper PSU, suitability and layout then.

 

[KSTR]

I was comparing the 5532 to the LME4562 and just when I thought I had a "tell," at least one of the 4562 units started popcorning.

Many pros avoid LM4562 like the plague because of their tendency to produce the dreaded popcorn noise. I have personally seen failure rates of more than 50% on some batches (and the company I worked for lost a lot of money from that). That was 15 years ago and I never touched an LM4562 ever since.

 

[Sokel]

Many pros avoid LM4562 like the plague because of their tendency to produce the dreaded popcorn noise. I have personally seen failure rates of more than 50% on some batches (and the company I worked for lost a lot of money from that). That was 15 years ago and I never touched an LM4562 ever since.

And I thought LME49720 was fragile, thanks for the info.

 

[KSTR]

LME49720 and LM4562 is the exact same chip (the original LM4562 name was only kept to kept purchase agents happy ;-)

 

[cgallery]

Many pros avoid LM4562 like the plague because of their tendency to produce the dreaded popcorn noise. I have personally seen failure rates of more than 50% on some batches (and the company I worked for lost a lot of money from that). That was 15 years ago and I never touched an LM4562 ever since.

The funny thing is, I had already had an awful experience with a phono stage that used three of the 4562s. I thought it was just the design of that phono stage. It wasn't until my tests in that A07 amp and then in another phono stage yielded similar results that I gave up.

And these were all different chips. The chips I was trying in the A07 were from Digikey. The chips in the three 4562 phono stage were from the manufacturer, and I tried one more that was from the same batch from Digikey but unused until that point.

They start great and then suddenly they gave me grief.

 

[brunoccj]

LME49720 and LM4562 is the exact same chip (the original LM4562 name was only kept to kept purchase agents happy ;-)

Try LME49860. It's 49720 with finer/smoother treble.

 

[solderdude]

Description
The LME49720 device is part of the ultra-low
distortion, low noise, high slew rate operational
amplifier series optimized and fully specified for high
performance, high fidelity applications. Combining
advanced leading-edge process technology with
state-of-the-art circuit design, the LME49720 audio
operational amplifiers deliver superior audio signal
amplification for outstanding audio performance. The
LME49720 combines extremely low voltage noise
density (2.7nV/√Hz) with vanishingly low THD+N
(0.00003%) to easily satisfy the most demanding
audio applications.

DESCRIPTION
The LME49860 is part of the ultra-low
distortion, low noise, high slew rate operational
amplifier series optimized and fully specified for high
performance, high fidelity applications. Combining
advanced leading-edge process technology with
state-of-the-art circuit design, the LME49860 audio
operational amplifiers deliver superior audio signal
amplification for outstanding audio performance. The
LME49860 combines extremely low voltage noise
density (2.7nV/√Hz) with vanishingly low THD+N
(0.00003%) to easily satisfy the most demanding
audio applications.

If only it had 'finer/smoother treble' in its description it would be more plausible.

 

[RexrothPigeon]

Try LME49860. It's 49720 with finer/smoother treble.

 

[KSTR]

Try LME49860. It's 49720 with finer/smoother treble.

Again, it is very very likely the exact same chip as 49720/4562, even TI support says so. The 49860 simply rated with a higher absolute max supply voltage, but all specifications are really 100% identical to the most minute detail.
We have to thank TI/NS for these same chips with different names because they created the perfect test scenario to show false positives ;-)

 

[BeeKay]

Again, it is very very likely the exact same chip as 49720/4562, even TI support says so. The 49860 simply rated with a higher absolute max supply voltage, but all specifications are really 100% identical to the most minute detail.
We have to thank TI/NS for these same chips with different names because they created the perfect test scenario to show false positives ;-)

Pure gold!

And to those “I know how to hear, I trust my ears”

 

[Sokel]

And as we're there and the game is starting to get funny, how come Audiophonics have TI LM4562NA/NOPB for 3.5 euro while Mouser's price is 7.5 euro???

 

[voodooless]

And as we're there and the game is starting to get funny, how come Audiophonics have TI LM4562NA/NOPB for 3.5 euro while Mouser's price is 7.5 euro???

Because that’s the price for one of them. If you buy in bulk, you get much much better prices elsewhere:

https://octopart.com/search?q=LM4562NA&currency=USD&specs=0

 

[Sokel]

Because that’s the price for one of them. If you buy in bulk, you get much much better prices elsewhere:

https://octopart.com/search?q=LM4562NA&currency=USD&specs=0

I know that, but even so it's 4.4 euro/piece for 2500 pieces at Mouser.
Something does not add up.

 

[voodooless]

I know that, but even so it's 4.4 euro/piece for 2500 pieces at Mouser.
Something does not add up.

This is quite normal for these kinds of components. Generally one does not buy in bulk from Mouser either if one’s values a competitive price.

 

[pma]

And as we're there and the game is starting to get funny, how come Audiophonics have TI LM4562NA/NOPB for 3.5 euro while Mouser's price is 7.5 euro???

I am extremely suspicious to opamp parts offered by Audiophonics. The prices do not make sense and the photos (OPA627) are suspicious again.

 

[Sokel]

I am extremely suspicious to opamp parts offered by Audiophonics. The prices do not make sense and the photos (OPA627) are suspicious again.

I'm on the verge to buy a bunch and measure them, just out of curiosity.
We'll see...

 

[Digital_Thor]

Easy, if you can find an opamp for your given project - use it.
If you want something specific that you can't find ready made - build it.
This is how everything else originated at some point in time.