ULTIMATE OPAMP SHOOTOUT... Where you get to decide.

Which opamp do you prefer the sonics of ?

  • Apple

    Votes: 2 5.0%
  • Banana

    Votes: 7 17.5%
  • Damson

    Votes: 1 2.5%
  • Kiwi

    Votes: 1 2.5%
  • Orange

    Votes: 6 15.0%
  • Peach

    Votes: 6 15.0%
  • Pear

    Votes: 3 7.5%
  • Pomegranate

    Votes: 11 27.5%
  • Raison

    Votes: 2 5.0%
  • Satsuma

    Votes: 1 2.5%

  • Total voters
    40
  • Poll closed .
We'll zoom in quite a bit closer, what do people think now - note that you can now see the individual data points:

PeachDistortion2.png

Also note the sampling rate, 44.1kHz, labelled on the left ...
 
OK, looks like a false alarm - so easy to get fooled by the reconstruction 'magic' at the output of the DAC. Resampled to 176.4kHz, so the waveform starts to look a lot more 'analogue', and the seeming artifact disappears ...

PeachOK.png

The problem "appeared" to be there because of the precise timing of very high frequency audio peaks:
 
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It may indicate to poor quality of the "direct" sound used for the test.
Yes, we didn't have the master file in the test. But once we did, even it sounds very much like the others.

If there is any similar test in future, I would suggest to use wav files for comparisons, exactly matched in level.
I listened to only the wav files. Their levels were very closely matched. Close enough, I would say. When I did my Mud Vs Wire test, level matching was difficult. I used tones at 150, 440, 5K to set levels before recording the samples. Even that required some minor tweaks in post to get perfect matching levels.

The people who are testing the samples should not use cheap PC motherboard soundchips and cheap headphones or plastic speakers
Agreed, but even on the best system I have, it's still hard to hear the difference. The Foobar ABX plugin is the best thing I know for solo blind testing. It will play the files simultaneously so that you can pop back and forth. Or you can play them sequentially if you like. Try going back and forth between A/B and be honest with yourself. Can you hear the difference? Then move on to ABX if you think you can.
 
My Blind Test Notes

When I looked again at my blind test notes, I feel it might be useful for future reference. Accuracy aside, it was a very honest perception because it is a blind test. There are other impressions that I didn't documented, such as when I found the music was so enjoyable or so terrible in the background, I checked my iPod and it was always associated with banana (direct) and satsuma (4558). Pomegranate is unique as it has special quality to the sound but perform terrible.

In the second picture you will find my final blind test regarding banana (direct) and orange (OPA134) to decide which one is best, because from the early blind test (picture one) Orange "outperformed" banana due to the soundstage, vocal and its ability to round the sharp ends (violin). After the final blind test between the two it was clear to me the superiority of the banana.
 

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They do need a different approach in use. Not a straight swap by any means. I suppose the attraction would be if they had a "specific sound" that could be attributed to them, a "sound" that some like (in a way that say marks out a valve amp). Technically they have the ability to offer enhanced performance in some areas (speed... but then again how fast do you need), and in other areas perhaps less good than conventional devices.
 
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This is a very good remark. Interestingly enough, there are parts with a "specific sound" though you measure quite nothing with available methods. This has been keeping me surprised for at least 10 years ;)

The age old problem :D Our inability to measure and accurately identify the minute subtleties that cause us to prefer one "xyz" over another similar "xyz"
 
This is a very good remark. Interestingly enough, there are parts with a "specific sound" though you measure quite nothing with available methods. This has been keeping me surprised for at least 10 years ;)
This is where the industry has stuffed up, big time. Obsessed with using conventional techniques for measuring things, it has made no progress in distinguishing parts and implementation techniques, which people with attuned hearing have no problem in separating, or grading. Hence the whole 'snake oil' industry, etc - it only has itself to blame ...

Nothing surprising really, inflexibility in thinking has been with mankind since year dot ...
 
That's brilliant Jay :) and it really is the best way to do it.

The current feedback opamps (the LT1229) might be worth working with in future perhaps really optimising the circuitry to suit them.

Apparently my amps (MC2 Audio) use a current feedback driver stage, at least that is what their blurb says.

I always assumed that they use a cf opamp but I've never looked inside one.
 
They do need a different approach in use. Not a straight swap by any means. I suppose the attraction would be if they had a "specific sound" that could be attributed to them, a "sound" that some like (in a way that say marks out a valve amp). Technically they have the ability to offer enhanced performance in some areas (speed... but then again how fast do you need), and in other areas perhaps less good than conventional devices.

From my blind test notes, the chip performed very well with complex passage or high speed (and it's just a trio). Coz the other high slew rate opamps have similar tendency, I must state here that my notes regarding lm4562 ("what a terrible sound") was not addressed at music#4 (the trio). I just don't have the column for general impression there.

This might be used in the "marketing" of such opamp???
 
Coz the other high slew rate opamps have similar tendency, I must state here that my notes regarding lm4562 ("what a terrible sound") was not addressed at music#4 (the trio).
This is as good an example as any of the fact that putting high performance parts in a situation guarantees absolutely ... nothing - quite often it will make things worse! The word is balance, balance, balance ...

Get a mediocre car, stick on the highest performance tyres you can buy - that will obviously turn it into a street dominator ... :p !