Amplifier Op-amp Rolling Part 2 [Video]

[SIY]

As I have said already a couple of times; I am not buying lunch for a room of blind listeners. Plus I do this for fun.

I have built and used the "H2 HARMONIC GENERATOR". I have measured the output and can hear the difference particularly with the gain turned up. That was only a half blind test, with one eye closed.

"This is an educational toy to me."

While we are at it, ASR has also done "Exactly zero actual listening tests".

Tell us more about "blatantly false".

The marketing piece you linked to had no listening data.And you are explicit that you won’t bother but double down on unsubstantiated and unlikely claims.

So yeah, blatantly false.

 

[DualTriode]

blatantly fase.

Using words that you do not understand except to be demeaning.

 

[amirm]

Using words that you do not understand except to be demeaning.

Watch it. You are out of line.

 

[rdenney]

“Room full of blind listeners”?

How sensitive of you.

You can start with yourself. The blindness is that neither you nor the person doing the switching knows which device is being played. Switching is done at random. One of the two devices is marked both A and B. The other is marked C. Every trial is either A vs B or C versus B. You write down which trial is the match and which is the different pair. You don’t know which pair is being compared, and your answer is either “same” or “different”.

You have to be careful—no tells! Output has to be matched using a precise voltmeter when played a 1KHz tone. No switching sounds characteristic of one or the other. Absolutely no clipping if you are comparing amps!

If you can detect a difference with statistical reliability, only then do you get to have a preference.

You only have to buy yourself and your switcher lunch. You were going to have to do that anyway.

Personally, I can’t tell a difference between, say, amps of adequate power without all that palaver, but that doesn’t require proof because it makes no claim. I have compared a Carver PM300, a Samson Servo 500, two B&K Reference 125.2, and a Buckeye NC502MP. The B&K amps were audiophile-approved, but the Carver was not and the Samson is a cheap PA amp with no claims to greatness. No difference I could hear at moderately loud levels—the loudest the least of them could achieve without clipping dynamic material. The Buckeye is the best from my perspective because it is the most powerful and the least likely to clip when playing really loud. And preamps are harder to distinguish than amps.

Rick “the B&K’s made too much heat for where they were installed” Denney

 

[Ismapics]

This dude is totally at odds with you Amir LOL

Another YT talking head that does no have an iota of technical knowledge. Analyst ? WTH. 0 credibility in addition that this person is in his late 50 or early 60's. That means like all humans, must be early presbicusis. So there is no way he can hear better than others same age.

 

[Ismapics]

The thing with OP Amps is just great marketing. It gives us a way to play with our gear and change things that we can later claim did a whole lot of difference. While of the brands is another way to take more money from consumers. Just like power conditioners, cables and famous Darko door stoppers. This is exacerbated by Youtube talking heads that claim they are the best thing since Swiss cheese. You want believe your ears. I can recall a few years back the reviewer the lives in his basement, talking up OP Amp switching. Now they have brought it from the Headphone scene to the amp and speakers side.

As I have said before companies no longer have where to spend their A&P other than shows and sending free product to all these YT talking heads for review. How many times have you seen the same speaker go from reviewers to reviewer same with expensive Amps. The brands just send products and the reviewers all of them always find great things to say and one little flaw. You know so they say they are not paid by the brand. When in reality all of them (few exceptions) are paid. As if they start being over;y critical the free gear train would stop and content would be hard to make. Take Darko, Z, Robinson, Gutenberg, all, create only content from gear sent to them. They all also claim golden ears and we already addressed that.

 

[solderdude]

I have built and used the "H2 HARMONIC GENERATOR". I have measured the output and can hear the difference particularly with the gain turned up. That was only a half blind test, with one eye closed.

"This is an educational toy to me."

DT... if you want a real educational toy download 'distort' program made by @pkane

This way you don't have to guess (or measure) how much of what harmonics are added but you can simply put in what you want.

Beta Test: DISTORT - audibility of distortions

DeltaWave beta-test was a huge success, thanks to all of you! This new beta-test is again, only for the brave and the curious :) Introducing DISTORT - free software designed to help determine the audibility thresholds of various audio distortions with your own equipment, at your own pace, with...

www.audiosciencereview.com

 

[MAB]

Except he (Carver) likely didn't.

Certainly, given the test methodology, he (Carver) didn't have to.

 

[MAB]

Yes it is audible, especially as you turn up the gain. We are not speaking of flat top clipping, just honest stair stepping harmonic distortion.

What do you mean by this? Especially, what is "honest stair stepping harmonic distortion"?

 

[pma]

Distortion added by software like Distort is quite dissimilar to distortion produced by amplifier electronic circuits. Software distortion does not reflect on frequency dependence of distortion, cross-over phenomena, dead-zone distortion in class D stages. In fact it is a different discipline and its results are hardly transferable to real circuits regarding audibility.

 

[solderdude]

Very true, just not for the circuit DT mentioned.
That circuit is just a 'blunt' device where one would have to adjust the volume to 'select' distortion generated by a FET in a non-linear area.
With distort you can simply set distortion levels and profiles. This can't be done wity that circuit.
There is no frequency dependency of distortion, no cross-over phenomena, no dead-zone distortion etc.

 

[xanalog]

I had to confirm that there is no such relevant English word as:

fase

So, I am trying to figure out if 'faRce" would be more...

out of line

...than "faLse"... but I won't ask which one!

Hey, don't yell at me: I am just trying to put a on an errant typo!

 

[SIY]

Hey, don't yell at me: I am just trying to put a on an errant typo!

Quite the opposite, I always appreciate corrections.

 

[DearSX]

Op amp rolling is an art, something which cannot be measured and is subjective. Sound is in the " head"; I mean ear of the beholder.

 

[rdenney]

Op amp rolling is an art, something which cannot be measured and is subjective. Sound is in the --head-- ear of the beholder.

Demonstrate it with real data. Subjective data is fine if it’s properly controlled.

Rick “not really from Missouri” Denney

 

[amirm]

Op amp rolling is an art, something which cannot be measured and is subjective. Sound is in the " head"; I mean ear of the beholder.

How do you know it can't be measured?

 

[DearSX]

How do you know it can't be measured?

I meant an "Art" can't be measured. Sorry, I was just joking

 

[DualTriode]

Very true, just not for the circuit DT mentioned.
That circuit is just a 'blunt' device where one would have to adjust the volume to 'select' distortion generated by a FET in a non-linear area.
With distort you can simply set distortion levels and profiles. This can't be done wity that circuit.
There is no frequency dependency of distortion, no cross-over phenomena, no dead-zone distortion etc.

You can setup the output from the jFet circuit just as you would the output of your CD or RIAA pre-amp.
On my bench the jFet output goes to the Benchmark preamp, the listening SPL is set with the Benchmark remote control, the same as with any other input device.

Also note that by adjusting the jFet supply voltage and or the bias current you can select any operating point and distortion profile on the jFet curves. The most distortion or the sweet spot with the least distortion.

It is like putting cream in your coffee, it is a matter of taste.

 

[solderdude]

You can setup the output from the jFet circuit just as you would the output of your CD or RIAA pre-amp.
On my bench the jFet output goes to the Benchmark preamp, the listening SPL is set with the Benchmark remote control, the same as with any other input device.

Also note that by adjusting the jFet supply voltage and or the bias current you can select any operating point and distortion profile on the jFet curves. The most distortion or the sweet spot with the least distortion.

It is like putting cream in your coffee, it is a matter of taste.



View attachment 447807View attachment 447808

You can only set it up properly when you have an ability to measure what you are doing.
I have no doubt this is the case when you use it.
The program distort is much more versatile was my point.

 

[SIY]

The program distort is much more versatile was my point.

It is indeed, but it has one disadvantage: it allows easy ears-only evaluation, something that True Audiophiles avoid like Dracula and garlic. It's so much easier and more fun to make evidence-free claims.