Blind test: opamp rolling in the Pearl 3 phonostage

TNT

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We all love the "suga"... strange really, why not the original... perhaps we don't know what the original sound like anymore but have created an internal ideal... how many here have visited an un-amplified music event the last 12 months?

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Official Court Jester
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yeah

certainly thing needed to be aware of and (hopefully) strive to, but becomes very tricky if one develops obsession

even if subjective, objectivity can be created only if starting from knowledge point, then proceed carefully

anyhow, properly executed blind testing can reveal much, sometimes even can of worms is more than welcome

that's why I said it was pity not all OP packages did allow anonymizing, to get it fully blind
 
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But DO they actually sound different?

I can't hear the difference between the tone controls of my Marantz amp being switched on or off (with bass and treble set to 0, obviously), yet three JRC NJM2068s are switched into the signal path for the tone controls to work.

This had me think about the validity of the so called HDAM modules that Marantz boasts about. Aren't they mostly a high end audio/marketing gimmick? The experiment of this thread shows that a high slew rate isn't necessarily needed for perceived good audio reproduction.
Could you say the same about other discrete opamps, like the Burson modules?
 
Dear Wayne,
Your statement immediately caught my attention: You really did put two 741s into your test setup ... and the result was a dominant harmonic distortion ... really?

That's really interesting, because I would never have seriously considered using a 741 myself, even though I know for a fact that it will and would do its job perfectly here.

Interesting.

Kind Regards,
HBt.
 
...and there you have it.
No!
Not automatically!

Do it yourself, and examine each stage separately, systematically and with understanding - you have the possibilities and the expertise, don't you?

We don't know anything yet. We simply do not yet know the WHY.

In both positions, a 741 derivative performed most spectacularly in terms of sound. Asked the other way round, and for each candidate individually, why did they not perform as expected in the sound check?

Greetings,
HBt.
 
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But DO they actually sound different?
Yes. I'm pretty convinced the treble is clearer now (and harsher, with some recordings) with the LME49720. More distinct lyrics. It's clear to me that one's choice of recordings will influence what op-amps sound good or not.

If I'd been listening using a series crossover + low DF amp when I rolled this op-amp, instead of the parallel crossover + high DF amp I'm using now, I'm certain the treble buzz and grate of the former setup would have been less pleasant. So the rest of the system also matters as to what op-amps sound good or not.
 
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Spectacular is maybe putting it too strong. To my/our ears it was the best of this range of 7 opamps. Double blind testing is the gold standard of research for sure.
A necessarily limited range of opamps and a really small sample of testers is not a gold standard...
This project is very interesting I do think, but I should not like to make it larger and more important than it is.
Other tests like this but with far more participants could be really worthwhile I think.
 
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The original HDAM is a discrete OP with a well known dual jFet, folded cascode, current mirror and symmetrical jFet output. All components are Toshiba's best choice ... etc.pp.

So not bad.

You got the number with the SR exactly right - "jitter".

;)
The ones in my amp are just BJTs.
There's the SA2-module with KTA1268 and KTC3200 and the SA3-module with KTA1517 and KTC3911.
 
Could you say the same about other discrete opamps, like the Burson modules?
Burson V6C was as obvious difference as night and day in i/v stage of pcm63 nos r2r dac comparing to most opamps. To me and to my peers. As mention here before, changes are obvious, now for better or worse that is in the eye of the beholder. Subjectivity is the word of this sport. You can eat as many pies in your life, but that one mama made, that one tastes the best :)

That being said, it depends on the devices you put opamp on, circuit, power supply, what it feeds. This opamp can sound amazing here to your taste buds, but won't be in some other device. Simply put, there are two ways, put in opamp of your budget, and forget, or spend money and try out different ones to find which one oils your cogs the best.
 
The operational amplifier in the input stage works as a current-voltage converter (also he is a part in the global loop) . The second operational amplifier does not (other things are in the loop). They are two places that like completely different types.

The hearing test is extremely interesting, but not really helpful. You first have to analyze the two stages separately and confirm them with measurements.