Some opamps to listen to.
Here we go then.
Links are at the bottom of the post
A selection of 5 different opamps tested as I outlined earlier using Doug Selfs tone control to give a pretty severe bass cut and treble boost followed by a mirror image correction.
You are hearing 7 opamps in the signal path twice over.
The opamps were:
All NE5532
All TI4558
All TLO72
We then have five LM4562 and two NE5532 (in the bass frequency network as I mentioned before).
Same again for five OP275 + two NE5532 devices.
Whatever you think of this type of test, please remember that any variation between the files presented here and the original unprocessed file is irrelevant.
This is very important to understand. Whatever defects/differences/loss of definition/increase of noise etc etc you might argue against these files, those differences are still valid information or data (call it what you will).
You are listening to determine if any differences exist between these devices.
As an analogy to that consider the following.
Norah Jones is in the recording studio. On either side we have two separate mixing rooms each with their own consoles, mics, mic amps. It would be reasonable to assume that both would produce different 'versions' of the same performance and yet both are 'masters' in their own right.
The same goes for these files. You are not comparing with them against anything else, each of these is a master in its own right.
Here are the Dropbox links. There are two compressed zip folders, one is marked as an MP3 for those on limited bandwidth allowance.
You do not need accept any offers or install anything. You just get the folders. And above all, enjoy 🙂
Comparison Files WAV
Comparison Files MP3
Here we go then.
Links are at the bottom of the post
A selection of 5 different opamps tested as I outlined earlier using Doug Selfs tone control to give a pretty severe bass cut and treble boost followed by a mirror image correction.
You are hearing 7 opamps in the signal path twice over.
The opamps were:
All NE5532
All TI4558
All TLO72
We then have five LM4562 and two NE5532 (in the bass frequency network as I mentioned before).
Same again for five OP275 + two NE5532 devices.
Whatever you think of this type of test, please remember that any variation between the files presented here and the original unprocessed file is irrelevant.
This is very important to understand. Whatever defects/differences/loss of definition/increase of noise etc etc you might argue against these files, those differences are still valid information or data (call it what you will).
You are listening to determine if any differences exist between these devices.
As an analogy to that consider the following.
Norah Jones is in the recording studio. On either side we have two separate mixing rooms each with their own consoles, mics, mic amps. It would be reasonable to assume that both would produce different 'versions' of the same performance and yet both are 'masters' in their own right.
The same goes for these files. You are not comparing with them against anything else, each of these is a master in its own right.
Here are the Dropbox links. There are two compressed zip folders, one is marked as an MP3 for those on limited bandwidth allowance.
You do not need accept any offers or install anything. You just get the folders. And above all, enjoy 🙂
Comparison Files WAV
Comparison Files MP3
Nothing in the PB system changes...same Android phone, same 3.5mm-3.5mm cable, same system etc.
Dan.
If the files are bit identical, which I think you said they are, then something in the PB system has altered - somewhere between the file and the grey squishy bit that completes the perception! 🙂
Opamps are great for industrial instrumentation , biomedical amplifiers etc.
I have used them since the 747 days but they do have a 'sound'.
If you are happy with opamps then use but I do not like the tightness of them.
Some do sound better than others but why fight it?
I have used them since the 747 days but they do have a 'sound'.
If you are happy with opamps then use but I do not like the tightness of them.
Some do sound better than others but why fight it?
question is can we actualy percieve difference that small,because measurments show there is difference.
how to measure our hearing? implant adc with wireless connection but not bluetooth inside part of brain used to process sound, but only after processing,or before?😀
when i was expecting difference of sound to be better , actualy was hearing better sound where it was very much worse, just by expecting better,even after measurments. so not only expectation bias is at work here.
how to measure our hearing? implant adc with wireless connection but not bluetooth inside part of brain used to process sound, but only after processing,or before?😀
when i was expecting difference of sound to be better , actualy was hearing better sound where it was very much worse, just by expecting better,even after measurments. so not only expectation bias is at work here.
You don't need an ADC there. Either the neurons fire or they don't. You can
directly tap the PCM. The world, as we perceive it, is digital. 😀
regards, Gerhard
Yes! But to get an idea, you first much establish your ability to hear distortions. And once you know your distortion threshold, then the question is simply whether or not one of two opamps have a distortion threshold that approaches your hearing limit. If yes, then you probably can hear a difference.
If not, then you likely cannot.
Op-amps for audio has distortion levels that are miniscule. Far below any one persons ability to hear.
Karl, thanks for uploading these files
I listened to them through headphones.
I can’t hear any difference, not even btn wav and mp3 files.
(I don't know which emoticon fits my case)
George
I can see why you restrict yourself to the "Lounge".
Obviously this sort of discussion/investigation on this topic belongs elsewhere.
Think I will not look substance in this thread, and should I manage to set up some tests, it will be necessary to discuss and present the results elsewhere.
As far as my troubleshooting and helping others?
Guess you'll have to do some searches and see for yourself.
Generally speaking, I don't care one way or another if you agree or disagree with me or anything I say. What I object to is the condescension of your posts - in this case directed at me, such as "... please answer your own questions, I'm not here to do your dirty work. Before you start playing hypotheses about this or that audible effect, surely you clearly understand the circuit theory and operation underlying those differences? ..."
Bottom line is that YOU CAN NOT answer, because you don't KNOW the answers - you may know the limited scope of your (presumed) engineering training, but not much more.
Fact is that YOU do not understand.
Probably you have some engineering background, and think that all that happens can be clearly described by what you have learned. If you are/were old enough, you'd have been around long enough to know and remember that there were people who said the SAME THING as you say now, 25+ years ago. Except that we now know that THEY did not KNOW the whole story, and since then a whole lot has been determined and discovered about WHY things sound a certain way.
I'd pretty much guarantee that in my lifetime I've "troubleshot" maybe 100 to 1000x the amount of gear that you have. Guarantee. Probably read more on electronics than you have too (although maybe not). But that does not cause me to view the world with arrogance, having a closed mind and being so insecure that I need to write hostile text as you have.
In addition I've likely designed and built more than you have - at least in audio. Have you bothered to look at my (now antique) website? Where's yours? Where are the pictures of gear you've built - audio or otherwise? Designed, audio or otherwise? Big secret?
Now you can attack me personally for saying that somehow these bits of "sand" don't seem to all sound nicely the same. But you are also attacking others here too in the same breath. You did see that Jacco said that he hears a difference between a 5534 and an LME4563 (think that was the part he cited)?? So, why not write something nasty about HIS engineering chops, while you are at it?
Because you might be listening on some mid-fi Pioneer receiver, with some sort of speaker system and that is "good enough for you", somehow you think that you can generalize from your own limited world to every one else's??
No.
HEY, you've got nothing to do, so why not whip out your distortion measuring gear, grab 10 of each type of opamp from your parts drawers, and try the "string of 10" distortion test?? Oh, wait, you say you do not have any of this?? Or do you?
Why not find something else to do with yourself and your time.
If you've got nothing constructive to say, say nothing.
Problem is, how can we be sure that we are not hearing things that do not exist? I can hear the differences of course. But what can you say, I can even hear difference between 2 identical files! 😀 May be I'm just a psychics... 😕
Imo, normal quality of the recording is actually needed, if we want to find out typical behaviours of normal opamps. Because, usually some opamps have strengths and weaknesses, and we have to choose our preference based on that complete list of strengths and weaknesses. If one specific weakness is missing from identification, we will only have the strengths!
(1) The Norah song is too slow to find the strength of 4562 in term of speed and resolution.
(2) The usual nervousness of 4562 is hard to perceive.
(3) TL072 is musical but usually has high noise. Here all files tend to have higher noise than usual, so it is hard to guess which one is the TL072.
Anyway, there is one file that stand out. From first listening, I knew that I would not miss it in ABX. It is THAT good. It has the musical details of JFET input opamps, but seems too good for a TL072, so I speculate that it is OP275, opamp that I have never heard before.
Attachments
Why, Bill? 😀
It's too confusing for you, is it? Admit it, you can't arrange the bits.
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In a multi-string (and each externally compensated for unity gain), single option left back then for a not-so poor student into chow.
When a new opamp arrives nowadays, they come as free sample batches, as e.g. the LM4562 you were referring to. All I need to do is switch them in/out circuit (at different gain setting steps with voltage divider) with the R/C output choice button of my preamplifier (120dB S/N, 10Hz-100KHz within 0.1dB, <1e-5 THD+N, all-discrete and hot as H)
Could be my hearing has never been all that grand, but opamps such as AD797 ('87), LT1028 (~same), OPA627/OPA637 ('90) up to LM4562 and recent LME types can be used to deliver excellent sound imo. Difference in e.g. noise figures, slew rate or max output current makes one better suited for a particular task. Pick the wrong one and it may deliver worse sound (or better for some, even though it's actually worse
)(Mr. Morinix's mentioned kV/µs slew-rate monsters have horrible noise figures, for phono use they'd not be directly in the signal path is my guess. Makes comments on power supply requirements not all-relevant for moderate slew rate opamps, imho)
Of course, what seems to have escaped most here is that if we lined up 10 or 15 discrete designs and took a listen we would hear _________ , _________ and ________
Just fill in the blanks according to what you believe you would hear
Just fill in the blanks according to what you believe you would hear
If you can hear differences then just score them in terms of which come across the best.
And look at it another way, are any particularly bad ?
Any chance of you sharing that with us ? I had never heard the OP275 either but I stuck half a dozen on an order a couple of months back and never had the chance to try them. The TI4558's were all new just yesterday as I grabbed them from the trade counter yesterday, and all for the princely sum of £0.12 each.
Attachments
I use Mr. Self's balanced/multi-parallel 5532 power amp design to drive K1000 headphones, different head-amp IC's/capacitors and the output stage opamps forced into class A.
Each opamp half delivers 1mA at 1.8V continuous for a 90dB SPL at my earlobes.
Anyone who can do better with a discrete design costing <10 times the invested amount is welcome to give me a howler, I'll fly over regardless of distance.
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And after all this and more has been done in the studio, we're trying to decide whether an opamp with 0.00008 thd would "improve" the sound over one with "just" 0.0001. Sound? What sound?
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