Op-amp Rolling Using AIYIMA A07

[PMB]

No, you are confused. I can give you two identical boxes, one painted red and another, black. Ask people if they sound different and a bunch of people say they do. Reason? They are not performing a controlled test with statistical rigor.

Let me give you a concrete example.

Our local audiophile group was invited to then one of the key writers/reviewers for stereophile magazine. We went to his home and he had a couple of high-end amps he was comparing. Room was small so we split into two groups. First group went in there, listened to bunch of music, and voted which amp was better. They came back and without telling us anything, we went to listen. We too were asked which sounded better. I did not vote because there was no way to tell given the poor protocol. But everyone else did.

We came back together and the first group asked which one our group liked better. The vocal majority answered to the shock of the first group as the pick was exactly opposite of theirs!!! Same test. Same room. Same protocol, but totally contradictory outcome with respect to what people "heard."

This is the problem with random audio testing that you all do. It doesn't generate reliable data. It generates randomness. Folks always assume there is a difference when many times there is not. Tests are not blind, nor repeated to rule out statistical errors. Watch that video. Learn how you properly evaluate fidelity. Then you are in a position to gather proper assessments. Only then you can come here and lecture us. Not before.

We know you are hearing differences. We would too if we were in your shoes. What separates us is that we don't trust those kind of tests. You on the other hand, have never learned the value of proper tests, nor studied research that indicates such, and are following along the same dirt road that get you lost as other audiophiles.

Audiophile is more than numbers where that video is absolutely and totally wrong. Of course if you haven't got a good hearing numbers are all you can rely on. Halve the people can't hear the differences and the other halve is easily influenced by brand/price that give expections. That's just reality in this hobby that is dictated by our hearing and brain trickery.

Then there is the point where you use the op amps. If it is something like top of the line amp differences are minimal because there are lot of other circuitry in support that your technical background certainly acknowledges . But good cheap Class D amps from China are a very good example what just changing the op amps can do hugely lifting the sound quality and value of the device almost making it indistinguishable from expensive A/AB amps. That's what this debate is mainly about a mild panic because today people can get good sound for $100-200 amps that arrivals vintage $2000-5000 systems.

Because we have different hearing we also like different colours of sound where the op amps gives the choice and not always pick the same choice. Matter of taste. Not sure how you find this offending and can't debate it making it worth of banning? I can hear the difference and if you can't lets just leave it to that. We all have different hearing.

 

[Antiaudiophile]

I rolled the op amps in my Aiyima A07 over a year ago with the Sparkos. I saw a youtube video that totally blew my understanding out of the water. The sparkos are not designed for that amp so the feedback circuit struggles to stabilize with such a fast and loud op amp. So it makes it less clear and harsh. I didn't realise though because it was louder, so louder is better right!? So I changed back to the original op amps and it is night and day. The original op amps stabilize the circuit and make it clear and full. It's a little quieter but I can more than make up the difference with a volume increase. Rolling op amps is snake oil. It usually destabilizes the feedback circuit leading to 'ringing'.

 

[Beave]

Audiophile is more than numbers where that video is absolutely and totally wrong. Of course if you haven't got a good hearing numbers are all you can rely on. Halve the people can't hear the differences and the other halve is easily influenced by brand/price that give expections. That's just reality in this hobby that is dictated by our hearing and brain trickery.

Then there is the point where you use the op amps. If it is something like top of the line amp differences are minimal because there are lot of other circuitry in support that your technical background certainly acknowledges . But good cheap Class D amps from China are a very good example what just changing the op amps can do hugely lifting the sound quality and value of the device almost making it indistinguishable from expensive A/AB amps. That's what this debate is mainly about a mild panic because today people can get good sound for $100-200 amps that arrivals vintage $2000-5000 systems.

Because we have different hearing we also like different colours of sound where the op amps gives the choice and not always pick the same choice. Matter of taste. Not sure how you find this offending and can't debate it making it worth of banning? I can hear the difference and if you can't lets just leave it to that. We all have different hearing.

Horse led to water. Won't drink.

 

[Antiaudiophile]

Audiophile is more than numbers where that video is absolutely and totally wrong. Of course if you haven't got a good hearing numbers are all you can rely on. Halve the people can't hear the differences and the other halve is easily influenced by brand/price that give expections. That's just reality in this hobby that is dictated by our hearing and brain trickery.

Then there is the point where you use the op amps. If it is something like top of the line amp differences are minimal because there are lot of other circuitry in support that your technical background certainly acknowledges . But good cheap Class D amps from China are a very good example what just changing the op amps can do hugely lifting the sound quality and value of the device almost making it indistinguishable from expensive A/AB amps. That's what this debate is mainly about a mild panic because today people can get good sound for $100-200 amps that arrivals vintage $2000-5000 systems.

Because we have different hearing we also like different colours of sound where the op amps gives the choice and not always pick the same choice. Matter of taste. Not sure how you find this offending and can't debate it making it worth of banning? I can hear the difference and if you can't lets just leave it to that. We all have different hearing.

I can hear the difference and it is much worse. I used Sparkos in my Aiyima A07 for over a year and wondered why it was so harsh. I had to use an EQ to mitigate it. As soon as I put the originals back in the feedback circuit stopped ringing and it was much clearer and less harsh, especially in the top end. I was able to back the EQ right off. An op amp that's not designed for a circuit will not match the feedback circuit's design in keeping the signal within range so the signal wobbles (extremely fast so it just comes off sounding less clear)

 

[MAB]

Another thread taken over by trolls.

 

[JSmith]

But good cheap Class D amps from China are a very good example what just changing the op amps can do hugely lifting the sound quality and value of the device almost making it indistinguishable from expensive A/AB amps.

This is complete nonsense... being ASR, posts like this are basically useless to the membership, without at least some basic evidence so others can try to replicate.

If you're interested, have a read about human biases and the way our brains work. It's rarely the device that causes a "night and day" difference.


JSmith

 

[dfuller]

I rolled the op amps in my Aiyima A07 over a year ago with the Sparkos. I saw a youtube video that totally blew my understanding out of the water. The sparkos are not designed for that amp so the feedback circuit struggles to stabilize with such a fast and loud op amp. So it makes it less clear and harsh. I didn't realise though because it was louder, so louder is better right!? So I changed back to the original op amps and it is night and day. The original op amps stabilize the circuit and make it clear and full. It's a little quieter but I can more than make up the difference with a volume increase. Rolling op amps is snake oil. It usually destabilizes the feedback circuit leading to 'ringing'.

You've found the conclusion I've come to with op-amp rolling: The stock op-amp is almost always the right one for the circuit.

Anyway, if anybody is curious, here's how a bunch of IC and discrete op amps measure:

https://www.nanovolt.ch/resources/ic_opamps/pdf/opamp_distortion.pdf

You will note that of all the discretes there, all of two of them compete with the cheap NE5532 in terms of typical linearity (though they can often be driven at higher rail voltages - 48V R-R - and seem to be less mad at driving low load impedances).