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What makes piano sound so hard to reproduce? - Page 10

post #136 of 191
Quote:
Originally Posted by nick_charles View Post
 

No need for that - the difference is big enough. Although I certainly agree it should be below 0.1 dB between the sources referenced usually to 1 kHz and I would have observed this if the differences were small enough to require it. Otherwise, the louder will always be "better" and win - perfectly aware of that. It is more likely that analog stages in DSD recorder used ( Korg MR1000 ) are not transparent enough - DSD at 5,6 MHz should be good enough, except for the very best cartridges (see below ).

 

I would like to stress that the difference I am talking about requires FAST equipment - from cartridge to loudspeaker or headphoine. A typical MM cartridge, that does roll off steeply just above the audio range, but is perfectly flat in the audible range ( say Stanton 681EEE, otherwise a very good cartridge ), is ill suited to such test - as is a loudspeaker with poor HF extension or so mangled phase response in the audible range ( some 3 ways definitely qualify as such ) to overshadow any differences between LP played "live" and recording to whatever medium. One end transducer that is fast enough and is not that rare and should be familiar to head-fiers would be any Stax Lambda electrostatic headphones driven with amp, not transformer.

Specified IIRC to 41 kHz or so.

 

The difference is not "night and day" - about the magnitude of the difference between a very good MM and very good MC as far imaging is concerned.

If you use end transducer that can not diferentiate among these, you have not had a chance to hear it yet. The frequency response of MM carts ( usual high impedance designs, low impedance ones can be as fast as they come ) is ROUGHLY  comparable to 44,1kHz/16 bit CD digital whereas DSD at 5,6 MHz ROUGHLY comparable to today's top MC cart response.

 

No digital that I know of capable of capturing the full 120 kHz bandwidth of Technics EPC P100CMK4 cartridge - hope one day to be lucky enough to have the money required and be there at the right time and right place in order to get one of these. 

post #137 of 191
Quote:
Originally Posted by bigshot View Post

Im sorry if I offended any microphones.

 

Microphones can be a very sensitive lot............

 

Quote:
Originally Posted by bigshot View Post

One thing that is interesting about folks who have problems in sound science... They always seem to speak about specific brands of equipment and quote sales literature. Their opinions revolve around products. You don't see that as much among the SS regulars.

 

Sorry man, but I think I have seen just as much marketing spin and misinformation on this forum (in general) as in any other Head Fi forum.

 

Quote:
Originally Posted by bigshot View Post

I apologise if I have offended any LPs.

 

LPs can be a very sensitive and delicate lot.........

 

Quote:
Originally Posted by Lord Voldemort View Post

There are pros and cons to everything. For me, everything except the sound science forum is filled with opinions based on naive fantasies. 

 

Like I said, I see just as much misinformation in the whole Sci Forum as I do in any other Head Fi Forum.

Or to put this another way, there is just as much useful info in other forums as there is in Sci Forum.

Obviously you have to separate the wheat from the chaff.

 

Quote:
Originally Posted by Puranti View Post


Well I you take those critics as oversized ego or pontificating opinions that's too bad for you. I'm myself a complete ignorant in sound science but I know how to recognize a valid argument from another, and if I'm wrong I would be glad to be corrected.

Science is not a matter of ego.

 

I agree, true Science is not a matter of ego.

If you are really sincere about learning about the Science of Sound (and I'm quite certain that you are) then make sure you also look up other sources.

Wiki is not too bad, but I have seen the odd erroneous "statement" and "fact" there.

Try digging up a few acoustic & audio & electronic textbooks.

post #138 of 191
Quote:
Originally Posted by jaddie View Post

You might have seen an RIAA sticker on the box but there's no way the RIAA curve was actually pre-recorded on that tape!  Look at what the record curve is (shown in green), you'll understand why that would absolutely have to be post-tape.  If you tried to do that and stay below saturation, you'd have one very low-level (and thus noisy) tape on your hands.  There's already a little eq going on in the record, though fairly slight at 15ips.

 

 

And there's no reason to put it on the tape and subject it to the inaccuracies of tape response.  It's a fixed precision network that never need be touched, and sits inside the lathe electronics.

 

The bottom and top end rolloff was a means of packing more loud signal onto records.  But there is no standard for that EQ, it was used variably and on a per-project basis, and there were and are far better means of doing the same job.  

 

I also pre-date digital, like by a dozen career-years, I'll be we're within a decade in age. 

Now that makes technical sense!

BTW, thanks for clearing that up!

post #139 of 191

analogsurviver, can you hear the difference (<- that's a link to a small listening test)?

post #140 of 191
Quote:
Originally Posted by Chris J View Post

Now that makes technical sense!

BTW, thanks for clearing that up!

What, the RIAA EQ or the fact that I'm old?

 

By the way, what I've posted is a really over-simplified discussion of the curves.  We could do much better, just seems off-topic here.  It may be obvious, but just in case...the RIAA eq is standardized, the optional to or bottom roll-offs are not.

post #141 of 191
Quote:
Originally Posted by xnor View Post

analogsurviver, can you hear the difference (<- that's a link to a small listening test)?

Good - like challenges like that. Will download, convert to WAVs, load to Korg MR1000, ask a friend to play the samples that will be labeled as A.B and C at random for me while I listen blindfolded turned with back to the friend on the Stax Lambda Pro/SRM1MK2 and honestly report the results. I will also ask friend to take this test, we'll simply reverse the roles. Can not do it alone, as I would see in which resolution is recorded each sample either in foobar or Korg MR1000. Do not want to emty the AUDIO folder on MR1000, leaving only your A,B, C samples (coverted to WAV, Korg can not play FLACs ), which would allow me to take the advantage of random/shuffle play - too much hassle with uploading numerous short files again.

 

In a way, it will be repetition of the test the same friend required me to take about two years ago, because he wanted to be certain I do not BS him regarding SQ when we were deciding the best sounding way to record and edit the first CD of male choir where this friend was singing tenor and doing the mastering. It was on my insistance to turn away from my friend and his computer - I was capable of 100% correct results for about first 10 minutes, then listening fatigue sets in for me. Should not be a problem with 3 samples only. We were using AKG K 1000 in that test.

 

Please do not publish the results which is which publicly, but in PMs to those participating in test, with you acting as "moderator/keeper of the results". It might take a while we can arrange for this, as he is quite busy with his ever growing family.

 

P.S: After downloading just saw they are all in 96/24 format - will take a test when I weak up for real.


Edited by analogsurviver - 1/1/13 at 9:26pm
post #142 of 191

jaddie - enjoy reading your posts, nice to read pro experience with lacquer cutting.

 

One question - how much attention did you personally and on "general level in industry" pay to the correct azimuth of the cutting stylus ? Is that adjustable at all or it is at the mercy of each sample of recording stylus? I ask this because even test LPs from the same manufacturer but different time periods ( making the use of the same cutting stylus unlikely due to wear, even if cutter chain was the same ) differ slightly in azimuth - just as it does with phono cartridges, although to a much lesser degree.


Edited by analogsurviver - 1/1/13 at 10:00pm
post #143 of 191
Quote:
Originally Posted by analogsurviver View Post

jaddie - enjoy reading your posts, nice to read pro experience with lacquer cutting.

 

One question - how much attention did you personally and on "general level in industry" pay to the correct azimuth of the cutting stylus ? Is that adjustable at all or it is at the mercy of each sample of recording stylus? I ask this because even test LPs from the same manufacturer but different time periods ( making the use of the same cutting stylus unlikely due to wear, even if cutter chain was the same ) differ slightly in azimuth - just as it does with phono cartridges, although to a much lesser degree.

There are adjustments for all physical alignments on the head and stylus, and yes, azimuth is there.  There are optical methods used to adjust the stylus position, but what you have to realize is this is one of those things that you can obsess about all day, but when it comes down to it, the precision to which the cutter stylus is aligned far exceeds the precision to which a turntable is usually aligned. The fact that you've taken the trouble to play test records that show up az issues (you're probably looking at channel separation, right?) is very unusual, and yes, that would show up misalignments like that.  But it's actually sort of a hyper sensitive test.  In practice, you can't actually hear small changes in channel separation once they're up where they belong.  What's odd about your observation is that test records weren't exactly made in the mass-quantity of a popular release. I would think there would be very little need to cut a fresh lacquer. You can get about 1000 pressings out of a stamper, and 8 to 10 stampers out of a mother, and about the same number of mothers out of a father, so all together they should have gotten something like 10,000 records before a new master would be needed, and if they did the 3 step process, something like 100,000 if memory servers.  That's a lot of boring test records! But possible they underestimated, and did the two-step process, got their 10,000 copies, then the record went platinum and the had to cut new masters.

 

Anyway... though I haven't surveyed labs to that detail, I would expect that once the stylus is aligned to a certain precision, they stop worrying about it.  Every change in the head and stylus would dictate a realignment, which the responsible labs would have done, to the best of their ability. But their reference is an optical process used to determine a physical position.  They couldn't use a playback cartridge to confirm it because that cartridge and stylus has the same alignment problem, so there are limits to how precise this adjustment can be.

 

As to industry or my personal practice in lathe alignment, full disclosure, I was not responsible for any lathe maintenance.  I was a client of the lab, not an employee.  Yes, I'm an engineer, but for those projects was hired to a rather odd position, that of technical supervision.  I was one of the engineers who designed and built the studio where the projects were recorded, and assisted during the sessions, then the record company hired me to track and supervise the projects technically all the way to production of the final releases, which were both vinyl and CD.  My solution to precision lathe calibration, and in fact, the entire analog mastering chain, was to work with the best lab I could find, interview them thoroughly, and then trust their team to make sure the gear was in peak condition.  Then I supervised the actual mastering sessions, observed and confirmed the operation of everything (contributed very little!) and left with the reference lacquers under my arm. I didn't supervise the process at the making of the metal parts or the process pressing plant, but again, hired the best I could find, and then beat them all up over bad test pressings anyway.  The process past cutting the lacquer is really difficult, and full of problems.  We went through several different vinyls, one bad mother/stamper combo, etc. At least half a dozen test pressings before we got a good one.  But right up to cutting the lacquers, it's pretty well in control.  Side note,  by contrast, the CD version came back perfect the first time.

 

And now, to put this "on topic"... our piano sound on those records was superb.  The Steinway D never sounded better. Whew.


Edited by jaddie - 1/2/13 at 10:21am
post #144 of 191
Quote:
Originally Posted by analogsurviver View Post

Good - like challenges like that. Will download, convert to WAVs, load to Korg MR1000, ask a friend to play the samples that will be labeled as A.B and C at random for me while I listen blindfolded turned with back to the friend on the Stax Lambda Pro/SRM1MK2 and honestly report the results. I will also ask friend to take this test, we'll simply reverse the roles. Can not do it alone, as I would see in which resolution is recorded each sample either in foobar or Korg MR1000. Do not want to emty the AUDIO folder on MR1000, leaving only your A,B, C samples (coverted to WAV, Korg can not play FLACs ), which would allow me to take the advantage of random/shuffle play - too much hassle with uploading numerous short files again.

 

You could also just use FooBar with the ABX plug-in - much simpler and also truly double-blind 

post #145 of 191
Quote:
Originally Posted by analogsurviver View Post

No need for that - the difference is big enough.

 

You are still missing the point. Level matching is important but that is only a hygiene factor. The really important part is not knowing what you are listening to and therefore reducing the vast pantheon of human biases that we all are prone to . In the Masters and Clark experiment a strong theme was just how wholly and utterly convinced sighted listeners were that they could reliably and accurately (and describe in great detail) distinguish between two stimuli when they knew which they were listening to and how this certainty (and the huge perceived differences) vanished when the unsubtle clue of knowing what they were listening to was removed. Biases however work both ways. Way back someone started a thread on high-res vs redbook and linked to samples. I was convinced that I could not tell the difference between them and I was right (sighted)  they sounded exactly the same. Then I did a DBT and found I could actually tell them apart , there was a slight but audible blip (artifact) on one sample and careful blind testing revealed it to me (14/15) . DBT is very sensitive and has been used to demonstrate the weaknesses of sighted listening in several in studies by Harman , Tom Nousaine and others. here is an interesting and accessible article on some biases  http://www.nousaine.com/pdfs/Can%20You%20Trust%20Your%20Ears.pdf  - here is a more extensive list http://rationalwiki.org/wiki/List_of_cognitive_biases

 

 

 

post #146 of 191
Xnor has helped him with his test. The three files appear identical. I'll be interested in hearing the results.
post #147 of 191
Quote:
Originally Posted by analogsurviver View Post

P.S: After downloading just saw they are all in 96/24 format - will take a test when I weak up for real.

You having a winter sleep? wink.gif

post #148 of 191
When he saw that the files all appeared identical, he got very busy, didn't he?
post #149 of 191

Come on, guys. He probably works for a living, and not in front of a computer like some of us. A little patience and benefit of the doubt, please biggrin.gif

post #150 of 191
Quote:
Originally Posted by jaddie View Post

What, the RIAA EQ or the fact that I'm old?

 

By the way, what I've posted is a really over-simplified discussion of the curves.  We could do much better, just seems off-topic here.  It may be obvious, but just in case...the RIAA eq is standardized, the optional to or bottom roll-offs are not.

 

Both!  wink_face.gif

 

Well.....we meandered off topic and you cleared it up.

thx.

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