[439598]

Im interested in op amp rolling for my amp since its not expensive to try out and I was surprised to find a lot of variation between them, the amp has a very simple circuit so my results could be more siginificant than with other amps. Using hd600s and 400is to test them

Ive compared the NE5532, NJM4556 and LM4562 so far.

LM is the best overall, it sounds the most balanced, very natural/smooth/clean, doesnt exaggerate anything but can sound lacking in impact. strangely its probably the most boring sounding one when paired with 400i but the best sounding with hd600
NJM has a more analytical, detailed sound but it sounds a bit thin and isnt as smooth... This is also used in o2 amp and it sounds like this op amp defines the analytical sound of that amp, I will have to try the LM in the o2.
NE was the most coloured sounding, seemed to hide a lot of details but had a fairly musical, mid-focused sound, could sound uncontrolled in very intense tracks... however there was loud pops and click when powering on and off the amp with the particular IC I had, seemed to work ok otherwise but I ordered a replacement to be sure I heard its real sound.

I am curious to see if there is more room to improve with other op amps?

So far I read the OPA2134 as an upgrade to the LM but its quite expensive, has anyone experience with this op amp or do you know any op amps that you consider an upgrade from the LM4562?

 

[Strangelove424]

This probably isn’t the answer you want, but I’m going to present it to you anyway. An op amp is part of a larger circuit and is chosen because its specs match those required for the circuit. The sound quality comes from the entire circuit, not the op amp. Switching op amps is likely to cause as much harm as good. For instance, in this post I am responding to one of many people who burned out a Burson v5: https://www.head-fi.org/threads/mat...p-and-excellent.475618/page-341#post-13652862

The Burson v5 is an especially egregious situation because Burson went out of their way to create a low-volume audiophile op amp that bolstered features like gold plated connection, channel separation, and EMI shielding. Features that would appeal to the audiophile crowd willing to spend an insane $60 on an op amp. Then they went out a suggested that their op amp could be used as a direct replacement for almost any other op amp on the market, despite having different voltage specs! The level of irresponsibility here is repugnant, and the reasons for failure seen in my post have displayed themselves rampantly in the wild. You would be far better off with a good ‘ole tried and true Texas Instruments 49860 beater. BTW, 49990 is a just a cherry picked lme49860 for wider voltage range, so don’t believe the kool-aid when everyone says they sound better… it’s the same op amp.

Obviously, not every op amp is a piece of junk like Burson’s but the trend for audiophile op amps (Muse is another popular one) imho is a form of snake oil. The job of the amplifier should be to provide clean gain. If you would like to alter the tone of the amp, do so with DSP such as EQ. Those changes will be controllable, and immediate. No opening up your amp, waiting 10 minutes for the caps to discharge, going in with pliers, and then losing all audio memory of what it sounded like before. With EQ, you can hear it immediately and tune to get exactly what you want. When you alter the sound signature with an op amp, more than likely you are just making the amplifier perform non-linearly. I’ve had op amps before I though “increased detail” and upon further inspection just increased harmonic distortion in the treble. That DAC I rolled op amps in came with its own flat factory measurements made with a $15k SYS-2722. I look back and wonder what I was thinking to mess with precisely measured perfection. I could only make it deviate from that perfection. All I did when I tried rolling op amps was mess up good engineering.

This is a good read about op amp myths: http://nwavguy.blogspot.com/2011/08/op-amps-myths-facts.html

 

[439598]

This probably isn’t the answer you want, but I’m going to present it to you anyway. An op amp is part of a larger circuit and is chosen because its specs match those required for the circuit. The sound quality comes from the entire circuit, not the op amp. Switching op amps is likely to cause as much harm as good. For instance, in this post I am responding to one of many people who burned out a Burson v5: https://www.head-fi.org/threads/mat...p-and-excellent.475618/page-341#post-13652862

The Burson v5 is an especially egregious situation because Burson went out of their way to create a low-volume audiophile op amp that bolstered features like gold plated connection, channel separation, and EMI shielding. Features that would appeal to the audiophile crowd willing to spend an insane $60 on an op amp. Then they went out a suggested that their op amp could be used as a direct replacement for almost any other op amp on the market, despite having different voltage specs! The level of irresponsibility here is repugnant, and the reasons for failure seen in my post have displayed themselves rampantly in the wild. You would be far better off with a good ‘ole tried and true Texas Instruments 49860 beater. BTW, 49990 is a just a cherry picked lme49860 for wider voltage range, so don’t believe the kool-aid when everyone says they sound better… it’s the same op amp.

Obviously, not every op amp is a piece of junk like Burson’s but the trend for audiophile op amps (Muse is another popular one) imho is a form of snake oil. The job of the amplifier should be to provide clean gain. If you would like to alter the tone of the amp, do so with DSP such as EQ. Those changes will be controllable, and immediate. No opening up your amp, waiting 10 minutes for the caps to discharge, going in with pliers, and then losing all audio memory of what it sounded like before. With EQ, you can hear it immediately and tune to get exactly what you want. When you alter the sound signature with an op amp, more than likely you are just making the amplifier perform non-linearly. I’ve had op amps before I though “increased detail” and upon further inspection just increased harmonic distortion in the treble. That DAC I rolled op amps in came with its own flat factory measurements made with a $15k SYS-2722. I look back and wonder what I was thinking to mess with precisely measured perfection. I could only make it deviate from that perfection. All I did when I tried rolling op amps was mess up good engineering.

This is a good read about op amp myths: http://nwavguy.blogspot.com/2011/08/op-amps-myths-facts.html

I think what you are saying is true in most circumstances nowadays, i actually tried rolling the o2 amp's 4456 for something else but it always sounded off, the 4456 has a very high output current and the o2 was designed around that fact.

In the other case of this amp that I built rolling the op amp completely changes the sound, going from the original ne5532 to the lm4562 refined/changed the sound to a point where I stopped thinking of the amp as fun project and started using over the o2 (though only with the 400i). the sound difference was what I imagine rolling a tube sounds like (I also designed this with the dip socket exposed on the underside so its as simple as tube rolling)... I think this could be down to the sheer simplicity of the amp but also highlights how significant the op amp can influence the sound.

I believe CMOY amps employ similar simple designs where the op amp has a massive effect on the sound, thought I might get some replies from people who have tested some of the more expensive op amps in these kind of circuits

 

[Strangelove424]

I’m mainly talking about commercial pre-built amps like the O2 that have been engineered and sold according to a standard of measured performance. It’s tough to improve the performance without redesigning the whole amp. In fact, the opamp myth link I pasted was from the O2’s original designer.

For DIY amps, there are forums for electrical engineering hobbyists that can help suggest an op amp that will fit for your particular circuit design. Sure, a DIY amp is going to require some op amp rolling for testing, after all you are the one engineering it. In that case, it would also be a good idea to measure each op amp’s performance as well, depending on the equipment you have access to.

 

[allhifi]

This probably isn’t the answer you want, but I’m going to present it to you anyway. An op amp is part of a larger circuit and is chosen because its specs match those required for the circuit. The sound quality comes from the entire circuit, not the op amp. Switching op amps is likely to cause as much harm as good. For instance, in this post I am responding to one of many people who burned out a Burson v5: https://www.head-fi.org/threads/mat...p-and-excellent.475618/page-341#post-13652862

The Burson v5 is an especially egregious situation because Burson went out of their way to create a low-volume audiophile op amp that bolstered features like gold plated connection, channel separation, and EMI shielding. Features that would appeal to the audiophile crowd willing to spend an insane $60 on an op amp. Then they went out a suggested that their op amp could be used as a direct replacement for almost any other op amp on the market, despite having different voltage specs! The level of irresponsibility here is repugnant, and the reasons for failure seen in my post have displayed themselves rampantly in the wild. You would be far better off with a good ‘ole tried and true Texas Instruments 49860 beater. BTW, 49990 is a just a cherry picked lme49860 for wider voltage range, so don’t believe the kool-aid when everyone says they sound better… it’s the same op amp.

Obviously, not every op amp is a piece of junk like Burson’s but the trend for audiophile op amps (Muse is another popular one) imho is a form of snake oil. The job of the amplifier should be to provide clean gain. If you would like to alter the tone of the amp, do so with DSP such as EQ. Those changes will be controllable, and immediate. No opening up your amp, waiting 10 minutes for the caps to discharge, going in with pliers, and then losing all audio memory of what it sounded like before. With EQ, you can hear it immediately and tune to get exactly what you want. When you alter the sound signature with an op amp, more than likely you are just making the amplifier perform non-linearly. I’ve had op amps before I though “increased detail” and upon further inspection just increased harmonic distortion in the treble. That DAC I rolled op amps in came with its own flat factory measurements made with a $15k SYS-2722. I look back and wonder what I was thinking to mess with precisely measured perfection. I could only make it deviate from that perfection. All I did when I tried rolling op amps was mess up good engineering.

This is a good read about op amp myths: http://nwavguy.blogspot.com/2011/08/op-amps-myths-facts.html

sl424: You offer some cautious advice. It's always wise to pay heed to such concerns as raised. Yet, I hear this so often, that I must take exception on your assertion that:

" ...... and then losing all audio memory of what it sounded like before."

Whoever spoke to this -put it into the hi-fi buff's conscience- should be hung-out to dry. Whoever it was, perhaps it was simply an age-old theory (that went viral) 40 years ago, some "scientific" BS that perpetuates itself endlessly when discussing sound quality observations.

In my head/memory, I can vividly recall both the sound -and the feeling- of superior hi-fi. In 2003/4 I clearly recall the first time I heard a Chord DAC (and recall it to this day; the effortless (flowing-like-water) clarity, dimensionality, tunefulness/distinctive tonal hues -the sheer musical naturalness of this DAC. Same can be said for various other components / brands/ models of hi-fi.
A most recent example (happened twice) was when one's head turns (in the direction of the music) to take note of where/what is playing. In both cases, weeks apart, a Brinkmann 'Bardo' turntable was the source. The sound so compelling, rich, real, it draws us closer. We/some can hear it from another room ! Such components are few/far between, but those that hear it, you see, becomes almost DNA-infused into our subconscious -it's the 'memory/feeling' we associate, inextricably linked to our hearing.

This notion of "Oh, I forgot what it sounded like (how I felt) a moment ago" is pure Bunk. Please, let us all dispense with this erroneous notion that we can't/don't recall (or can't instantly identify great (or poor) sound. Almost ANYONE can; neighbor's, children, wives (if not audiophiles), grandma's/grandpa's, heck likely even cat's/dog's !

To think that sound is a complete, well-understood "science" (as it relates to human interpretation) is both untrue, and unwise. Let's make that clear, and keep this in mind when discussing the intricacies of part/component selection, cabling, and even non-signal devices such as hi-fi equipment racks/shelving -ALL can have a profound impact upon sound quality. An open, educated (yet humble) mind, however, is a prerequisite.

I for one, would be the first to caution audiophiles considering spending a small fortune on -whatever; seek/consider something more practical/affordable is stressed often.
That's not to say I shun, disapprove of, premium, legitimate, superb hi-fi components/or cabling. Not at all. Those products however, must earn their keep; repeatedly demonstrate sensational performance/attributes -with a supportive consensus (spanning months/years) to qualify.

We (the industry), test procedures/instruments are/will continue to evolve -particularly once it's determined what 'we' should be looking for.

In the meantime, humans explore -it's our nature. Every century or so, there is one who debunks the myth's (held firm for too long) that re-sets, in fact establishes actual truths. Albert Einstein was one such chap, early last century. Who shall come next/what field remains to be seen. But you can bet on the fact that new 'truths' shall surface -satisfying even those that must see it on paper to believe it -as in a formula/specification sheet, for example.

Yet, audiophiles the world over need not (and don't) wait for any scientific rationale to tell them how to feel -or hear. They've made the leap; they trust their intuitions, sensibilities and are not afraid to express what they feel/see, or hear -and shall continue to intrepidly, explore ...

peter jasz

 

[bigshot]

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

 

[Speedskater]

In my head/memory, I can vividly recall both the sound -and the feeling- of superior hi-fi.

For the very small differences likely to be heard between well chosen op-amps, your memory will start to fade in 10 seconds.

We (the industry), test procedures/instruments are/will continue to evolve -particularly once it's determined what 'we' should be looking for.

The test procedures/instruments industry has a far more than adequate portfolio of tests. If a person can hear a difference in electronic circuits, there are tests that can easily measure that difference.

 

[439598]

 

[allhifi]

For the very small differences likely to be heard between well chosen op-amps, your memory will start to fade in 10 seconds.


The test procedures/instruments industry has a far more than adequate portfolio of tests. If a person can hear a difference in electronic circuits, there are tests that can easily measure that difference.

I see. You say:


" ...For the very small differences likely to be heard between well chosen op-amps, your memory will start to fade in 10 seconds."

If such suggested 'small' differences are noted, it hardly represents a difference at all -or rather, not a very consequential one. In which case
near anybody/everybody would say -and so save time and money, i.e. no loss/gain. Ninety-nine percent of the passionate music lover's/audiophiles
I know would truly rather spend money on anything else than the imaginary 'benefits/improvements' that come from such considerations/up-grades.
Which begs the question: Why would (serious) listener's go out of their way (and often times at considerable expense) to consider /make such changes
if its barely audible ? Answer; they don't.

allhifi said:
" ...We (the industry), test procedures/instruments are/will continue to evolve -particularly once it's determined what 'we' should be looking for."

The test procedures/instruments industry has a far more than adequate portfolio of tests. If a person can hear a difference in electronic circuits, there are tests that can easily measure that difference.

Really ? Which ones, specifically (or generally) ?

pj

 

[Speedskater]

The test procedures/instruments industry has a far more than adequate portfolio of tests. If a person can hear a difference in electronic circuits, there are tests that can easily measure that difference.

Really ? Which ones, specifically (or generally) ?

Well for one, the newer Audio Precision instruments have a portfolio of over 200 tests.
* * * * * * * * * * * * * * *
Bob Cordell in his book 'Designing Audio Power Amplifiers' has 40 pages on audio tests and test instruments.

 

[allhifi]

Well for one, the newer Audio Precision instruments have a portfolio of over 200 tests.
* * * * * * * * * * * * * * *
Bob Cordell in his book 'Designing Audio Power Amplifiers' has 40 pages on audio tests and test instruments.

I asked a simple question, and your reply is quoting somebody's book -with over "200" tests, yet you can't point to ONE
that shows your assertion that: " ...If a person can hear a difference in electronic circuits, there are tests that can easily
measure that difference." ?

Name one.

pj

 

[castleofargh]

sl424: You offer some cautious advice. It's always wise to pay heed to such concerns as raised. Yet, I hear this so often, that I must take exception on your assertion that:

" ...... and then losing all audio memory of what it sounded like before."

Whoever spoke to this -put it into the hi-fi buff's conscience- should be hung-out to dry. Whoever it was, perhaps it was simply an age-old theory (that went viral) 40 years ago, some "scientific" BS that perpetuates itself endlessly when discussing sound quality observations.

In my head/memory, I can vividly recall both the sound -and the feeling- of superior hi-fi. In 2003/4 I clearly recall the first time I heard a Chord DAC (and recall it to this day; the effortless (flowing-like-water) clarity, dimensionality, tunefulness/distinctive tonal hues -the sheer musical naturalness of this DAC. Same can be said for various other components / brands/ models of hi-fi.
A most recent example (happened twice) was when one's head turns (in the direction of the music) to take note of where/what is playing. In both cases, weeks apart, a Brinkmann 'Bardo' turntable was the source. The sound so compelling, rich, real, it draws us closer. We/some can hear it from another room ! Such components are few/far between, but those that hear it, you see, becomes almost DNA-infused into our subconscious -it's the 'memory/feeling' we associate, inextricably linked to our hearing.

This notion of "Oh, I forgot what it sounded like (how I felt) a moment ago" is pure Bunk. Please, let us all dispense with this erroneous notion that we can't/don't recall (or can't instantly identify great (or poor) sound. Almost ANYONE can; neighbor's, children, wives (if not audiophiles), grandma's/grandpa's, heck likely even cat's/dog's !

To think that sound is a complete, well-understood "science" (as it relates to human interpretation) is both untrue, and unwise. Let's make that clear, and keep this in mind when discussing the intricacies of part/component selection, cabling, and even non-signal devices such as hi-fi equipment racks/shelving -ALL can have a profound impact upon sound quality. An open, educated (yet humble) mind, however, is a prerequisite.

I for one, would be the first to caution audiophiles considering spending a small fortune on -whatever; seek/consider something more practical/affordable is stressed often.
That's not to say I shun, disapprove of, premium, legitimate, superb hi-fi components/or cabling. Not at all. Those products however, must earn their keep; repeatedly demonstrate sensational performance/attributes -with a supportive consensus (spanning months/years) to qualify.

We (the industry), test procedures/instruments are/will continue to evolve -particularly once it's determined what 'we' should be looking for.

In the meantime, humans explore -it's our nature. Every century or so, there is one who debunks the myth's (held firm for too long) that re-sets, in fact establishes actual truths. Albert Einstein was one such chap, early last century. Who shall come next/what field remains to be seen. But you can bet on the fact that new 'truths' shall surface -satisfying even those that must see it on paper to believe it -as in a formula/specification sheet, for example.

Yet, audiophiles the world over need not (and don't) wait for any scientific rationale to tell them how to feel -or hear. They've made the leap; they trust their intuitions, sensibilities and are not afraid to express what they feel/see, or hear -and shall continue to intrepidly, explore ...

peter jasz

Why would you dig out this thread just to show that you haven't read anything about human memory and psychology? I'm very confused and a little annoyed.

 

[Speedskater]

I asked a simple question, and your reply is quoting somebody's book -with over "200" tests, yet you can't point to ONE
that shows your assertion that: " ...If a person can hear a difference in electronic circuits, there are tests that can easily
measure that difference." ?
Name one.
pj

Not all simple questions have simple answers. That's why one instrument can do over 200 different tests and a book requires 40 pages to cover just some of them.

 

[Speedskater]

The basic tests are:
1] signal level
2] frequency response
3] distortion tests. 1st level are THD & SINAD
4] noise and interference
5] ringing and oscillation
* * * * * * * * * * * *
for op-amps the first test that I would do is for ringing and oscillation, up to 30 megahertz.

 

[bigshot]

Why would (serious) listener's go out of their way (and often times at considerable expense) to consider /make such changes
if its barely audible ?

That question is simple to answer...

1.) Compulsive Shopping - Every day in Head-Fi, you can read hundreds of posts by people who buy new DACs or amps when they already have five or six of them already. They don't buy them because something is wrong with their old amps specifically. They buy them because they enjoy the process of shopping, waiting for the package to arrive, unpacking, setting up and posting about their new purchase. It's the same in a lot of hobbies... People with dozens of guitars who really don't play very well, people who spend more time buying camera equipment than actually shooting photographs, people who buy books, records and videos without enough time to read, listen or watch all of them. (I plead guilty to that one myself!)

2.) Peer Pressure - On Head-Fi you see people insisting that the piece of gear they just bought is "night and day" better than anything else on the market. Someone with less experience might look at that and say to themselves, "That guy uses all those fancy technical terms and refers to all those model numbers, he must know more than I do." So they go out and buy whatever was being touted simply because someone convinced them that they should.

3.) Upsell - Related to peer pressure is the pressure salesmen put on their customers to spend more money than they should. If a salesman sees that a customer is definitely going to buy something, he starts to cleverly lead the customer away from what he is leaning towards buying and starts suggesting models that are a little bit more expensive. Or he might suggest accessorizing - buying high end cables or power conditioners or other things that make absolutely no difference at all. This is a time honored American tradition, and everyone who has ever worked in retail has been taught how to do this.

4.) Ego Gratification - This is one of the most powerful drives among audiophiles. The Macintosh brand name really impresses the neighbors, and it's even more impressive when your whole system lights up aqua. The more you spend, the more impressed people get and that feeds your ego. Most people can't tell the difference between a cubic zirconia and a diamond, but people still buy diamonds that cost a hundred times more, just because of the status involved with owning a particularly rare hunk of rock. Audiophiles flatter themselves claiming that their hearing is more discerning than the average person. They lord it over other people on the forum and the justification for that is 100% based on the price tag of their rig. It's a lot harder to gain respect by actually achieving something- writing a book, building a business, raising brilliant children. It's easier to just go out and buy respect.

5.) Fear - Any salesman will tell you that the greatest motivator to buy is fear. "If I don't jump on this deal right now, I will regret it for the rest of my life." Listen carefully, and you'll find that fear is the last thing they use to try to close a sale. In audiophile circles, the fear is that perhaps there is some element of sound you can't hear right now that will become obvious and irritating in the future. "The might sound good to you right now, but after a few hours listening fatigue might set in..." "Yes, MP3s sound good, but there is a reason they call them lossy. They are missing parts of the sound. That may not bother you now, but in the future who knows?" This was the big selling point of SACDs and HD audio. Everyone can read the specs and see that the difference between a CD and an SACD all lies outside the range of human hearing, but still people lay in bed and worry about the potential sound they can't hear, but maybe it might actually make a difference. The truth is that there is nothing there to hear.

6.) Fetishism - People have a natural tendency to focus on certain things. They might be tempted to buy a whole system in one particular brand just so all the faceplates match. One interconnect of a different color drives them crazy. It's a milder form of OCD. I had a friend who would go crazy if the CDs in his CD cases weren't put in the case with the type on the CD facing the right way. I was visiting with him once and I put a CD away for him, and I watched him get up, walk over to the shelf of CDs, pull it back out and straighten the alignment and put it back again. The thought of a CD being out of line was unbearable to him. It's the same thing with vinyl collectors. LPs don't actually sound better than CDs, but playing them is a tactile process... pulling them out of the sleeve carefully, cleaning the record, setting the needle down in the right groove, turning the record over when a side is done... It's a fetishistic routine that some people enjoy. And that enjoyment is more important to them than sound quality.

7.) Bias - All of these things are illogical, but human beings are illogical creatures. We don't just buy things because they are better than what we already have, and we don't just spend money on things that benefit us. Often we spend money on things that are exactly the same as what we already have. The reason we do that isn't all that complex. It's based on the way bias works. Bias isn't logical, but it is extremely powerful. We can't just will it away. It isn't a bad thing either... without bias, we would spend so much time making all the millions of decisions we make in a day that we would have no time left to actually do anything. Bias is a shortcut to decision-making. But not everyone is aware of that, so they labor under the illusion that they make rational decisions when they don't actually do that. It's very difficult to convince these people of their bias. In fact, if you've read this far, your bias is probably making you itch to say that none of this applies to you. That is drop dead proof that you are laboring under the illusion of rationality, because the most rational people in the world realize they have strong bias and implement controls on their important decision-making to disable bias as much as they humanly can.

Answer; they don't.

Of course, you answered your own question I quoted at the top to discourage anyone from contradicting you and to proactively let us know you aren't subject to compulsive shopping, peer pressure, ego gratification, fear, fetishism, and bias. But I'll reach my own verdict too... Everyone is affected by these things to different degrees, and you're no different. You're an anonymous name in an internet forum, so you can pretend to be Spock, Albert Einstein and the Dalai Lama rolled into one if you want. But you're just a regular garden variety human being when it comes to these sorts of things, I'm afraid. All of us are.

By the way, I posted an article about auditory memory with lots of information and citations. Did you read it? If not, why not? Here it is again in case you missed it. https://en.wikipedia.org/wiki/Echoic_memory

As for measuring things we can hear, I'd suggest googling the aspect of sound you want to find out about (distortion, frequency response, dynamic range, etc.) and add the term "threshold of perception" to it. But you're going backwards with this argument. Measurement of sound goes back over a century, and sound technology is able to record sounds that is audibly transparent. I don't know how we could do that if we couldn't measure what constitutes audible transparency.