1.) How much material is there on a properly cut record? (I don't know if there are losses)
2.) Your point wouldn't surprise me. Most reviewers are older and probably beat their ears to death. Not good for top end response.
DVV--DBT does well to set a limit of audibility, even if we set our standards to that of the most exceptional individual within a set of listeners (or just beyond that). We can talk preferences until we're blue in the face, but knowing what the limits of a young (undamaged), trained ear can actually hear is a critical first step, because it sets the boundary.
That and, Olive/Toole's work seems to strongly suggest that we as a greater population (accepting moderate deviation) tends to prefer a similar sound under DBT, which speaks directly contrary your point. So at least that tells me that I'd probably do well to align my goals with the common preference in the absence of better information.
So, no, DBT does NOT pull wool over anyone's eyes. It tempers unjustified enthusiasm. No, I don't expect you to do DBT within your own home unless you're the curious type. But, then again, you should really stick with, "I like this or that in my system" rather than "this or that is better". Note the difference? That's what this issue is about and why SY (more vocally than perhaps others) calls out the people/industry he does, as they're claiming something as absolutely better without any sort of attempt to remove biases.
Perhaps you're more fallible than you think? Or maybe not. The issue is you don't really know!
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Well musical instruments have significant energy at harmonics, certainly to 10kHz. Electronic music has used higher fundamentals than the piccolo of course. But certainly the pink noise contours are pretty much obeyed for the high stuff. But a response to at least 15kHz used to be considered standard. And then there was quad and the Shibata stylus...1.) How much material is there on a properly cut record? (I don't know if there are losses)
2.) Your point wouldn't surprise me. Most reviewers are older and probably beat their ears to death. Not good for top end response.
(2) And a lot of kids believe their ears are indestructible, sadly.
Thanks, Brad--my question was additionally answered by http://wiki.hydrogenaud.io/index.php?title=Myths_(Vinyl)
(In my ignorance, I didn't know the tracking/response bandwidth of records -- seems in the 20 kHz -40 kHz range on the high end, but, as you note playback will depend on cartridge loading)
(In my ignorance, I didn't know the tracking/response bandwidth of records -- seems in the 20 kHz -40 kHz range on the high end, but, as you note playback will depend on cartridge loading)
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Derf, we have studied this in detail since the 70's. There is always a fair amount of high frequency energy ready to do mischief and this is what a quality phono playback has to be able to handle without being overstressed by TIM ( a common problem in the past) or just plain high frequency clipping.
If you think I am not serious, carefully study SY's tube phono stage and note its dynamic limits.
If you think I am not serious, carefully study SY's tube phono stage and note its dynamic limits.
That's a nice reference (note that the final parenthesis has to be added, as it got clipped off of the link as a link). So initially the thing comes up with no material. I repaired it above as part of the quote.
Be careful the guys at hydrogenaudio are not immune from being confused around dynamic range, SNR, effective noise BW of FFT's, etc. I could not find where someone computed 150dB DNR for CD. I can think off at least one wrong way to get that answer.
Yeah, that part (the dynamic range with dithering) didn't make sense to me, I was more looking at the bandwidth as a go/no go to 20 kHz than anything else. Seems at least, on the limits of the playback method, that this bandwidth is more than manageable, even if it's not necessarily exercised.
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10-4 John. Didn't want to suggest this wasn't known information--I just didn't know (and should have done due diligence before asking), as I'm a child of the digital era.
Thanks for the link/notes.Daniel
I've posted a survey article here before, the best noise shaped dither achieved 12dB improvement over TPDF when audibility was taken into account. That would look like -106-108dB or so perceived SNR. If you use quantization noise in one bin vs signal, with an FFT you can make it anything you like.
Derfnofred, I appreciate your reasonable and civil argumentation, but really do not want to run another circle on this well beaten path. I do not believe in DBT as anything but a bare pointer what to investigate. Over the years of reading mostly British audio magazins, I have tried and discovered that DBT actually tells me very little, but individual texts of some contributors (Alvin Gold comes to mind) are most useful for me, because ut appears that ontributor and I have very similar tastes and hearing. Ovwer the years, his findings very closely mirror my own, and then the difference is mostly in degree rather than the entire device. I also have a friend who has a totally different system to mine, yet our degree of agreement on the sound of this or that device is almost identical. I do not feel I need more confirmation than I already have.
DBT are, to me, just another mantra suported by those who do not have other mantras, but appear to need some. I do not deny their use for those who need them, but I do not. Just as classic THD measurement results are meaninful to those who need their instruments to tell them what they are hearing, while to me anything below 0.05% becomes essnetially meaningless. The question is, under which circumstances and into which loads- if that's into 3 Ohms in parallel with 2 uF at nominal power output, that's all I care about.
So, let's leave it at that, shall we?
I have a client who apparently believes that moving the cursor to be centered n the FFT baseline is an accurate reading of system noise. I don't know what the AP default binning is, but his results were unbelievable. One variable gain amp part for which the manufacturer quotes a typical output noise of 10.5uV at unity gain was said to have a noise floor down at -120dBu (775nV rms).
dvv, I did not test any of my amps with DBT.
And yes, the sound of the amps as I write about them is just my say-so.
However, if you read my write-ups, I am very careful not to make subjective claims based on technical matters. So, like government, I keep 'church and state' completely separate. One issue is to do with the mind (technical) and the other with the heart (subjective). When the two disagree, only the judge (DBT) can settle it.
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I would think in the sampling that the noise floor is pushed down, so this is probably optimistic.
That said, AP could add a function to compute the real noise - enter the BW and get a noise number out.
Yes of course it does have that capability, and I have been suggesting that he use it. They are just infatuated with FFTs.
EDIT: Oh wait I see what you are saying. It probably does have that function based on the FFT, but I was thinking more of the traditional filters and rms voltmeter capability.
My own position on DBT is somewhat ambivalent. The sighted tests, especially of loudspeakers, strongly favor big pretty boxes until they can't be seen anymore. The stress from quick evals of electronics is real, and I doubt that, other than in a few really terrible cases, that I would be very good at discerning differences (the Dynaco Stereo 120 was an example I cited, the schematic sent to me as a joke by Walt Jung, but I had indeed listened to them and thought I didn't like the sound).
But what I do object to are people who go on at great length about some tweak making an amazingly great difference, and that without it the music dies etc. When these people are unable to distinguish in a DBT the sound with and without the tweak, I am troubled.
But what I do object to are people who go on at great length about some tweak making an amazingly great difference, and that without it the music dies etc. When these people are unable to distinguish in a DBT the sound with and without the tweak, I am troubled.
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