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Discrete OpAmp Review: Sonic Imagery vs Sparkos

AdrianusG said:
Wow dude, perhaps next time try the "Decaf" ;)

peace.
Click to expand...
I think he just wandered into the wrong place. He'll be happier elsewhere.
 
Piere said:
Gee, we are below -130dB level here! What are we talking about, concerning audibility?
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I'll add that once upon a time, a long time ago, you could build discrete op-amps that handily beat monolithic. Those days are gone.
 
Anyone has used the LME49720? How about it compared to Sparkos labs SS3602?
 
Useful information for sure as I am refreshing a Music Hall integrated and some other gear. How did it sound? I never let a piece of gear get out my door until I am totally satisfied snd have done several listening sessions. It's audio gear after all but sometimes measured performance says nothing about the topology within which it is being applied. How it sounds is fun for me to hear, obviouasly.
 
From TI, "the input offset voltage (VOS) is defined as the voltage that must be applied between the two input terminals
of the op amp to obtain zero volts at the output". Some advanced DIY design such as by AMB, provide ability to zero out a voltage offset resulting from the opamp selection. That's the reason I wonder how 'clean' is opamp rolling in the buffer stage for an amplifier, if non-zero offset voltage is not compensated.

Will OPA637B work in the input buffer without oscillation or other issues that would require a circuit adjustment?

OPA637B is a remarkable audio opamp with the low noise 0.6 μVpp, high slew rate (135 V/μs), low offset voltage (typical +/-40μV) and settling time of 450ns to 0.01%. The downside is the price at $63.31 on Mouser as of this writing. OPA627B has even lower offset voltage at +/-25μV

For OPA1612A:
- slew rate: 27V/μs
- input voltage noise: 1.2 μVpp (20Hz to 20KHz)
- input offset voltage: +typical /-100μV
- settling time: absent in the datasheet

For SS3602 the datasheet lists:
- slew rate: 12V/μs (20 V/μs in positive direction, and 12 V/μs in negative direction)
- input voltage noise: (please check my calculation) 42,798.36 μVpp (with a 5 MHz bandwidth, Voltage Noise Density 2.9 nV/√Hz is approximately equivalent to 42,798.36 μVpp)
- input offset voltage: +/-300μV
- settling time: absent in the datasheet
 
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That's the reason I wonder how 'clean' is opamp rolling in the buffer stage for an amplifier, if non-zero offset voltage is not compensated.
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That's one of the warnings that more-seasoned people will give to the newcomers, especially when swapping BJT-input opamps into an equipment designed around MOSFET-input opamps; end-results of >100mV DC at the final output is not uncommon. NE5532 for example has almost 1uA of input bias current so if you have an impedance difference of 10kohms multipled by total gain of 10 and bam that's 100mV DC at the output.
 
Is it easy to swap the op amps? most op amps are around 50€

1730487006974.png
 
Doodski said:
Why spend money like ~$100 on OP amps when they make little to no change in the sound quality? Get better speakers if you want better sound.
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Thats what i am trying to do with my second new setup.

Bluesound Node Icon + APOLLON AUDIO PURIFI 1ET7040SA ST + Unknown speakers + SVS SB-1000 PRO
 
Mike_Trueman said:
Thats what i am trying to do with my second new setup.

Bluesound Node Icon + APOLLON AUDIO PURIFI 1ET7040SA ST + Unknown speakers + SVS SB-1000 PRO
Click to expand...
Put your money into the speakers and don't waste time, energy and resources on those OP amps. :D
 
Doodski said:
Put your money into the speakers and don't waste time, energy and resources on those OP amps. :D
Click to expand...
It’s interesting that most people in this little area of the internet have…..well not quite a hate on but definitely a disdain for discrete OP Amps. I had no experience nor expectations until I purchased the same DAC my neighbour had, the AUNE X8 Magic DAC. I liked the size and decided I’d try it out to see how an inexpensive DAC sounded. I have several other DAC’s, one a Musician Pegasus R2R solid state and the other the Havana Balanced NOS DAC. I set up AUNE in my system and listened over several weeks. It wasn’t anything special, it was a DAC and it did it’s job. I’m not going to go into specifics as to how much better or poorer it sounded against my other DAC’s, that’s not relevant here.
I had heard a number of reviews where you can swap out the OP amp to the Sparkos SS3602. I ended up emailing Sparkos and the SS3602 was purchased. I replaced the default OP amp with the SS3602 and waited a couple weeks. I’m not a big believer in “burn in” but wanted to get a feel for how it sounded. I did notice after I replaced the OP amp the imaging was way more precise and instruments sounded more real. “I’ll stop the fluttering now!) okay. I don’t trust myself…when it comes to putting in new components..literally. There’s a huge “I just paid and put this gizmo in so it better do something in your mind”. Hey! My neighbour has the same DAC. I called him and we decided we’d do the following on the weekend : set up both DAC’s side by side, made sure they were covered up by a blanket, keep every other component in the chain the same. My Daughter will be switching them back and forth. One has the Sparkos the other has the regular OP amp.
We listened for over a half an hour but the difference was not subtle, it was obvious. Vocals sounded more lifelike, The music had more life to it. The imaging a person experienced opened up. It was the Sparkos. There a lot of descriptions I can use but I’ll boil it down; the Sparkos dramatically improved the sound. It was not just “different”, it was “better”. We listened again repeatedly switching for over another half a hour. Remember all we were doing was unplugging the digital out from my AUDIOLAB 6000 CDT. Then we decided to do another test. We switched the Sparkos into his identical DAC and tried the test again. Again, the results were obvious. One of my Daughters twenty year old friends had dropped by at one point and sat in on it and she listened and picked the Sparkos out as well.
Now this is by no means a “technical measurement”. One could argue many things about this amateur test. However just consider this, our ears have been used for literally many many thousands of years as hunter gatherers. Evolution has refined them to point out objects in your field of view and behind you as well.
Yes, we can measure the discreet Op amps like the Sparkos and I won’t argue that point. However I would encourage any of you to at least consider replacing a solid state OP amp with a discreet OP amp. Sparkos isn’t the only one. I prefer his because he’s a decent young guy who’s started his family business and had their first child. I don’t know him personally but have corresponded with him. I don’t think I’d get that kind of response and help from Texas Instruments! Again, I’m only saying what I experienced with his Sparkos SS3602, there are others. What I will say is from what I've experienced it was well worth the money. To recap: I’m not one for gimmicks, I’m well aware of all the “hype” and blatant misinformation out in the Audio world. This was simply an attempt to let you folks know what I and my Neighbour have experienced.
Happy Holidays to all!
 
Genpattonj said:
It’s interesting that most people in this little area of the internet have…..well not quite a hate on but definitely a disdain for discrete OP Amps. I had no experience nor expectations until I purchased the same DAC my neighbour had, the AUNE X8 Magic DAC. I liked the size and decided I’d try it out to see how an inexpensive DAC sounded. I have several other DAC’s, one a Musician Pegasus R2R solid state and the other the Havana Balanced NOS DAC. I set up AUNE in my system and listened over several weeks. It wasn’t anything special, it was a DAC and it did it’s job. I’m not going to go into specifics as to how much better or poorer it sounded against my other DAC’s, that’s not relevant here.
I had heard a number of reviews where you can swap out the OP amp to the Sparkos SS3602. I ended up emailing Sparkos and the SS3602 was purchased. I replaced the default OP amp with the SS3602 and waited a couple weeks. I’m not a big believer in “burn in” but wanted to get a feel for how it sounded. I did notice after I replaced the OP amp the imaging was way more precise and instruments sounded more real. “I’ll stop the fluttering now!) okay. I don’t trust myself…when it comes to putting in new components..literally. There’s a huge “I just paid and put this gizmo in so it better do something in your mind”. Hey! My neighbour has the same DAC. I called him and we decided we’d do the following on the weekend : set up both DAC’s side by side, made sure they were covered up by a blanket, keep every other component in the chain the same. My Daughter will be switching them back and forth. One has the Sparkos the other has the regular OP amp.
We listened for over a half an hour but the difference was not subtle, it was obvious. Vocals sounded more lifelike, The music had more life to it. The imaging a person experienced opened up. It was the Sparkos. There a lot of descriptions I can use but I’ll boil it down; the Sparkos dramatically improved the sound. It was not just “different”, it was “better”. We listened again repeatedly switching for over another half a hour. Remember all we were doing was unplugging the digital out from my AUDIOLAB 6000 CDT. Then we decided to do another test. We switched the Sparkos into his identical DAC and tried the test again. Again, the results were obvious. One of my Daughters twenty year old friends had dropped by at one point and sat in on it and she listened and picked the Sparkos out as well.
Now this is by no means a “technical measurement”. One could argue many things about this amateur test. However just consider this, our ears have been used for literally many many thousands of years as hunter gatherers. Evolution has refined them to point out objects in your field of view and behind you as well.
Yes, we can measure the discreet Op amps like the Sparkos and I won’t argue that point. However I would encourage any of you to at least consider replacing a solid state OP amp with a discreet OP amp. Sparkos isn’t the only one. I prefer his because he’s a decent young guy who’s started his family business and had their first child. I don’t know him personally but have corresponded with him. I don’t think I’d get that kind of response and help from Texas Instruments! Again, I’m only saying what I experienced with his Sparkos SS3602, there are others. What I will say is from what I've experienced it was well worth the money. To recap: I’m not one for gimmicks, I’m well aware of all the “hype” and blatant misinformation out in the Audio world. This was simply an attempt to let you folks know what I and my Neighbour have experienced.
Happy Holidays to all!
Click to expand...
Nice story but stories are anecdotes and not proof.
 
Genpattonj said:
We listened for over a half an hour but the difference was not subtle, it was obvious. Vocals sounded more lifelike, The music had more life to it.
Click to expand...
Record it and let us all join in this miracle of 'not subtle sound quality improvement'.
Or... does the magic just go away as soon as one records it ?
After all... all recordings have been recorded at one point and they seem to capture the magic. It just takes a discrete opamp to let that pass... are those discrete ones used at the recording stage ? Can regular opamps be used in the recording but they cannot reproduce that but the amplifier after the buffer can ?

Confuses the hell out of me why no one records this phenomenon.

Ooohh right ... one can only hear it if the reproduction gear uses that opamp which none of us have ... or wait... can any amplifier 'amplify' the change and make it audible ?

My head is spinning...
 
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Genpattonj said:
It’s interesting that most people in this little area of the internet have…..well not quite a hate on but definitely a disdain for discrete OP Amps
Click to expand...
They don't work as well as the relatively cheap and mature NE5534 hundreds of which were probably used to make most of your recordings.
 
Genpattonj said:
well not quite a hate on but definitely a disdain for discrete OP Amps.
Click to expand...
They have their place in engineering. But better performance for this application can be had with monolithic opamps. There are things you can do with monolithic than cannot be done (as a practical matter) with discrete. I will certainly observe that engineering is more valued on this site than fashion, and discrete is the wrong engineering choice here.

Genpattonj said:
Now this is by no means a “technical measurement”
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No, nor is your listening "test" anything like an actual listening test. You have to have basic controls in place for any validity.
 
oleg87 said:
Wow, that sounds like a remarkable amount of sophisticated signal processing for a humble op-amp
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I wonder what happens if you put one of these into a coffee machine? Do the coffeephiles do such things?
 
I wish I had the kind of hearing that would allow me to also discern these differences...alas, I could hear no difference between chip op-amps and the free Burson V6's I was sent a while ago...they look cool, but nothing audible for me...
 
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