That's true but I don't readily see what it has to do with what's been discussed in this thread. Putting Occam's Razor thingie to one side for the mo, the theme has been that "Folk say that LDRs sound better but we know that they display higher distortion figures. The claims therefore have to be wrong because (this being implied) harmonic distortion - just look at my datasheets - is the only pertinent variable and is definitely perceptible. Advance to taste hypotheses to explain why they're wrong but we definitely, definitely don't need to listen to LDRs to be sure that they are wrong".
As I said prior, I no longer use LDRs but can definitely see the flaw in this argument (which I've parodied but not, I think, misrepresented). No recourse to Argument by Authority can change that.
The word is generally pejorative (see dictionary) and was unarguably used in a pejorative manner on this thread.
The reports are not data in the sense of electronic measurements of this or that but hundreds of similar reports pertaining to a shed load of LDR products are most certainly valid indications (aka data) of how their performance is perceived. (If you have some way of reporting individual perceptions absent subjective report, I'd love to hear it.) Agreed, they have no explicatory value (no-one claimed any) but citing a datasheet and/or a few casual measurements while refusing to listen to the wretched things has even less.
Dozens is probably more accurate. But on this site as Scott has mentioned you will find dozens of people with an undying love for SET amplifiers, and dozens how eschew all digital for love of vinyl. None of which is proof of anything other than humans have preferences, often illogical ones.
Other than impedance (causing FR variations) or distortion what magic do the LDR have?
Where are these shed loads of positive reports? How are they possibly biased in reporting (it's a pretty one-sided distribution, no?)? What other confounding factors do we need to at least hypothesize may be contributing?
I'm entirely okay with subjective evaluations: just blinded and controlled to at least give us a fighting chance of drawing something meaningful out of the results. At this level of internet reporting and sales pitches, the plural of anecdote isn't even good enough to worry about.
At the very least, the datasheet gives us some indication of the degree of change we might see in use. That's, at least, governed by physics and its effects discernible by casual measurement. And if they aren't casually measurable (given the performance of even the most modest of test equipment), then Bayes has something to say about the likelihood that the human can hear the difference.
I'll not quibble the point.
It neither proves nor disproves anything though it suggests to me that, as audio reproduction equipment varies widely in performance, some technologies better suit a given listener's experience, acuity and tastes than others. (You don't see many Heavy Metal fans with 3w SET amps.) That's neither logical nor illogical though I accept that there's much of the illogical in audio on, as I'm being reminded, both sides of the argument.
I don't recall suggesting they had any "magic" or commenting on FR variations (I'd need to see the data). I did describe my using LDRs non-optimally impedance-wise and switching to TVCs.
My experience was that LDRs sounded clearer than the likes of an Alps pot and the sort of SA I could afford. But I've not listened to SAs built with top-notch components.
My guess as to cause (and that's all it is though I'm not alone in making it) is that the mechanical aspects of pots and SAs (wipers, switches, etc) matter more than superficial assessments suggest. SA resistor quality definitely does: anyone who can't hear the difference between, say, Vishay Z-foil resistors and metal-film dittos at key points in a circuit is welcome to enjoy audio as a hobby but less so when lecturing others as to what can and can't be heard. Especially when they refuse to listen.
I would say those who are SURE that they can hear them are the ones who are in the glass houses with a pile of stones they should be careful about the use of.
Many have claimed wipers are evil and audible to sell things, and if there is a DC bias on a pot then there are measurable effects. But in any well designed circuit that is not an issue. Of course there are many poor circuits out there as well.
You up for an independently monitored DBT to test your theory? I am serious. Testing for audibility of wipers should be quite easy to setup.
I am sorry if I have interrupted your technical discussion with my real-world findings.
BTW have you done an audition with LDRs to inform us ?
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Wow here we go again, we're either deaf or liars. When I retire I think I will do my web survey of listening impressions of caps, resistors, or maybe op-amp rolls to collect a set of adjectives for each and see if there is any consistency at all.
LDR's have one thing in common with the op-amp rolls, the bass improvement, somehow that must the key to all this.
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Somehow I doubt that you are really sorry. You don't seem to be too interested in facts and figures. You weaseled out when you couldn't find the tech arguments.
No. Should I inform you? About what? Did I claim any audible attribute of these things?
Jan
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I wonder if these guys roll op-amps for that "extended" bass.
https://www.youtube.com/watch?v=7a0Z2yndlOs
https://www.youtube.com/watch?v=7a0Z2yndlOs
At least you have a sense of humor, the humorlessness these days is getting a little overbearing.
They need to extend their playing abilty just a bit, a few hours/months listening to Lou Reed
Metal Machine Music, would do wonders for them.
I have it on CD and LP ...https://www.youtube.com/watch?v=dYtzNl48F60
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I say, boy, pay attention when I’m talkin’ to ya, boy! This boy’s more mixed up than a feather in a whirlwind!
More LDR attenuator impressions
I have now done some more comparisons and have some impressions to share. This time I compared my old preamp with the LDR unit. The cd player and amplifier are identical to the system in the first comparisons. The speakers and room are different. The system I used today also has a subwoofer.
The "old preamp" is a prototype unit I built in 2011 from a Hugh Dean design that was the precursor to a possible new preamp from Aspen, but Hugh didn't go ahead with production. This preamp has a cfp gain stage of around 10db. and a cathode follower buffer. The volume control in it is a 20k shunt attenuator that I built up a dozen years ago from a Goldpoint kit.
I used the same Tchaikovsky piece, Romeo and Juliet, that I used in the first comparison. This time I compared bass performance and used only the subwoofer and played a piece from an XTC disc that I am very familiar with.
I did a simple A/B comparison with the preamp as the "A", but ended up going back and forth a few times.
My impressions this time are that the LDR is more transparent than the preamp and the orchestral climaxes have a bit more impact with the LDR than with the preamp. This is probably more in keeping with the other views expressed here on the differences between LDR's and a preamp. With the XTC piece I didn't really notice any appreciable difference in the bass with the subwoofer.
The speaker systems in my two audio systems are quite different. Perhaps my two listening comparisons are just more reflective of those differences than anything else.
Next up, one day soon, is a comparison of the 20k shunt attenuator, used as a passive, and the LDR.
I have now done some more comparisons and have some impressions to share. This time I compared my old preamp with the LDR unit. The cd player and amplifier are identical to the system in the first comparisons. The speakers and room are different. The system I used today also has a subwoofer.
The "old preamp" is a prototype unit I built in 2011 from a Hugh Dean design that was the precursor to a possible new preamp from Aspen, but Hugh didn't go ahead with production. This preamp has a cfp gain stage of around 10db. and a cathode follower buffer. The volume control in it is a 20k shunt attenuator that I built up a dozen years ago from a Goldpoint kit.
I used the same Tchaikovsky piece, Romeo and Juliet, that I used in the first comparison. This time I compared bass performance and used only the subwoofer and played a piece from an XTC disc that I am very familiar with.
I did a simple A/B comparison with the preamp as the "A", but ended up going back and forth a few times.
My impressions this time are that the LDR is more transparent than the preamp and the orchestral climaxes have a bit more impact with the LDR than with the preamp. This is probably more in keeping with the other views expressed here on the differences between LDR's and a preamp. With the XTC piece I didn't really notice any appreciable difference in the bass with the subwoofer.
The speaker systems in my two audio systems are quite different. Perhaps my two listening comparisons are just more reflective of those differences than anything else.
Next up, one day soon, is a comparison of the 20k shunt attenuator, used as a passive, and the LDR.