Quote from: Nessuno on 29 March, 2012, 06:26:22 AMMaybe the sense is that the practical limits of common hardware prevent you to reach the theoretical ones of the format?Many of the limits are not due to the use of common hardware, but due to the fact that even the best hardware ever made couldn't do anything about them.
Maybe the sense is that the practical limits of common hardware prevent you to reach the theoretical ones of the format?
Then there is the FM distortion caused by ............ offset angled tone arms (IOW not straight line).
[Having said that, playing vinyl twice inside of a short period of time is bad for the vinyl and you will not get the same signal off the record.
Quote from: mzil on 30 March, 2012, 03:33:29 AMQuote from: knutinh on 30 March, 2012, 02:36:26 AMOr, do a high-resolution digital recording of vinyl, play it back at high-resolution and CD-resolution in an ABX test.-kThat way wouldn't be comparing direct analog LP sound to digital, though; it would be comparing two kinds of digital sound.So what?We already know from other experiments that reasonably good digital is sonically transparent, and the very best digital bests the thresholds of human hearing by orders of magnitude.
Quote from: knutinh on 30 March, 2012, 02:36:26 AMOr, do a high-resolution digital recording of vinyl, play it back at high-resolution and CD-resolution in an ABX test.-kThat way wouldn't be comparing direct analog LP sound to digital, though; it would be comparing two kinds of digital sound.
Or, do a high-resolution digital recording of vinyl, play it back at high-resolution and CD-resolution in an ABX test.-k
Quote[Having said that, playing vinyl twice inside of a short period of time is bad for the vinyl and you will not get the same signal off the record.Where is the proof? Just claims pulled out of your behind?
Perhaps you should actually read up on the read mechanisms involved with contact stylii, and about plastic and elastic deformation in vinyl.
QuoteThen there is the FM distortion caused by ............ offset angled tone arms (IOW not straight line). That can be easily avoided:By kraut_2 at 2009-03-27
... To the best of my knowledge, linear trackers also have a non-zero (if constant) tracking angle since the cartridge has to drag the tonearm along. One would hope that those of the better kind used some kind of servo (à la power steering) to minimize both force and tracking angle, otherwise I'd imagine bearing friction would be extremely critical. ...
QuotePerhaps you should actually read up on the read mechanisms involved with contact stylii, and about plastic and elastic deformation in vinyl.Yes, I have done that enough over the last fifty years I play back vinyl.The statement was done categorically - so who please is unprofessional here - without reference to cartridge mass, tracking weight, tracking angle (not existing in tangential arme, airbearing or motor driven) etc. etc. I for instance run wet, so some lubrication of the interface stylus/track walls is provided reducing friction.
Many non-servo linear trackers use an air bearing (air is blown into the gap between the sleeve the tonearm is attached to, and the rod it slides on.) The arm platform has to be very precisely leveled, and the arm wires have to be carefully dressed (see the wires in the posted picture). For a good example of a servo powered integrated arm and turntable, consider the Technics SL-10 and SL-15.
Having said that, playing vinyl twice inside of a short period of time is bad for the vinyl and you will not get the same signal off the record.
...every time you take a record out of its sleeve, no matter how careful you can be, that's a scratch waiting to happen...
I find that about 1 out of 3 to 4 records I buy new today are already warped and/or have factory machine and handling marks right in the damned grooves. Sometimes I ask myself why I keep buying them.
Where is the proof? Just claims pulled out of your behind?
I'm simply citing the known facts. You claim otherwise, well, show us your evidence. Your claim is the extraordinary one, so you owe us extraordinary evidence.
If, for instance, you bother to read the AES collections on vinyl, you will find what you seek.
Quote[Having said that, playing vinyl twice inside of a short period of time is bad for the vinyl and you will not get the same signal off the record.I responded to this specific claim. He claims, he has to supply the proof. Not the other way round. ...
... I playback records wet and remove the residual moisture after playback.
And if you think my language is offensive - so be it, some statements do not deserve better than being severely offended against.
Dr. Bruce Maier (Discwasher principal), who put most of the blame onto stabilisers that are put into the record for anti-static and other reasons. One of these compounds is a co-polymer resin, vinyl acetate.
Lo and behold, the pH had increased 20 to 30 times. Once that acid is formed, it starts an automatic hydrolysis of the record surface. Now the record dries and spectral analysis reveals that these interfacial changes on the surface of the record cause a permanent puckering.'"
but I do think you'd better save your offenses for more serious matters
I play with a mixture with distilled water and 99% isopropyl alcohol (30% down mixed), and remove the liquid from the record surfaces immediately after playback is ended, removing any dirt, and eliminating static buildup.
Unfortunately the cited study was done by a company definitely not unbiased, with a stake in selling their particular product. So I have a problem trusting a study that runs contrary to my own experience over many many years, with the practices I employ.
The question is: as a copolymer it is not a freely available chemical, but bound in the polymer matrix. How reactive is it in this form at all? Again - another claim/blame without evidence?
That shows how "scientific" this so called Dr. is. An increase in pH does not means in increase in acidity, just the opposite. What an asshat....
My experience in vinyl over 50 years have audible proven to me that records when well treated can play with only minor surface noise repeatedly for a long time
QuoteThen there is the FM distortion caused by ............ offset angled tone arms (IOW not straight line). That can be easily avoided:By kraut_2 at 2009-03-27Quote[Having said that, playing vinyl twice inside of a short period of time is bad for the vinyl and you will not get the same signal off the record.Where is the proof? Just claims pulled out of your behind?
Lo and behold, the pH had increased 20 to 30 times.
The Limiting Tracking Weight of Gramophone Pickups for Negligible Groove DamageIt has been observed that when spherical styli are dragged over flat vinyl surfaces, scratches are produced under loads considerably exceeding the elastic limit as calculated from theory. The author, in this paper, describes the results of his experiments which bear out his argument that under load the point of yield begins below the surface; and reaches the surface, producing visible tracks, only after the calculated yield load is exceeded. This critical value of load for styli of various radii has been measured and found to be equivalent to, for a 1-mil stylus, 0.64 gm. for a 90° record groove. No size or skin effect was found with the vinyl material tested.Author: Barlow, D. A.Affiliation: Aluminium Laboratories, Ltd., Banbury, Oxon., EnglandJAES Volume 6 Issue 4 pp. 216-219; October 1958
Groove Deformation and Distortion in RecordingsThe elastic and plastic deformation of vinyl record compound under indenters of various profiles has been studied in large-scale tests. Curves of total depth of penetration versus load have been used to calculate the net distortion on record playback. In general, in the lower treble, net distortion is less, and in the upper treble, net distortion is greater than tracing distortion alone. This is important for attempts to reduce tracing distortion by inverse predistortion of the recorded signal. Nylon was also studied as a material with contrasting mechanical properties to vinyl. Further light has been shed on the nature of translation loss.Authors: Barlow, Donald A.; Garside, Gerald R.JAES Volume 26 Issue 7/8 pp. 498-510; August 1978
Comments on "On Stylus Wear and Surface Noise in Phonograph Playback System"When a set of conclusions is reached in a study as fundamental as this, it is certain that particular factors have been accepted as a part of the working hypothesis essential to the formulation of conclusions which are open to challenge by another student of the subject. Mr. Barlow's studies, like those of Prof. Hunt, are thorough and represent another view of the same subject. Almost invariably, the points of departure in such cases become the focal points for study by all concerned. The process of further investigation usully results in the collection of additional test data that removes the subject from the realm of scientific speculation, and places it within the established body of knowledge of the art. Readers wishing to offer supporting or different viewpoints of their own for publication are invited to address them to the Editor. Such comments are especially welcome.Author: Barlow, D. A.JAES Volume 4 Issue 3 pp. 116-119; July 1956
Determination of Sliding Friction Between Stylus and Record GrooveA method is presented for determining the coefficient of sliding friction between stylus and record groove. The method consists of measuring the time intervals required for a freely rotating record (on a turntable) to decelerate from one known speed to another, both with and without a stylus sliding in the record groove. The method as been used to evaluate the frictional characteristics of several brands of phonograph records in mind condition and after treatment with various preservatives, cleaners, and antistatic agents. Some test results are presentedAuthor: Pardee, Robert P.Affiliation: Ball Corporation, Aerospace Systems Division, Boulder, COJAES Volume 29 Issue 12 pp. 890-894; December 1981.
Disc Record Care and Cleaning AccessoriesSince the paper presented by me on a similar theme to the 50th AES Convention at the Cunard International Hotel in London in 1975, investigations into developments in this area have been pursued vigorously both in the UK and in other countries to tackle the problems of -record cleaning- and maintenance.Author: Aldous, DonaldAffiliation: Hi Fi News and Record Interview, PlymouthAES Convention:65 (February 1980)
An Investigation into the Increase of Non-Linear Distortion Products from Virgin Tape to Disc PlaybackA study was carried out in order to examine the increase in distortion products arising from the various stages in the recording process from virgin tape, via tape copies, right up to and including interaction with specific record pick-up distortions. 1 kHz sinusoidal signals as well as some IM (400 + 4000 Hz) and double tone (9800 + 10200 Hz) signals were recorded at levels increasing in discrete 3 dB steps starting in non-critical range and continuing up to tape compression level. The tape -original- and first and second generation copies were then transcribed together onto 12" LPs. This made possible a study of the distortion progression and also the second and third order distortion combination products. The current practice of recording right up to the modulation limits of the tapes as well as of the disc seems to result in a total distortion percentage which considerably degrades the sound quality. In order to gain an impression of the audible effect of these distortions, some special musical samples were recorded with the same discrete level steps as the measuring signals. These musical samples were subjected to the same copying and transcription processes as the measuring signals and were similar in character (single tone, multi tone). Listening to these musical sample records provided an opportunity to establish perceptibility limits for the human ear regarding amounts of disturbing distortion.Authors: Stephani, Otfried; Blüthgen, BjörnAffiliation: Polygram GmbH, Hanover, GermanyAES Convention:62 (March 1979) Paper Number:1453
An Experimental Study of Groove Deformation in Phonograph RecordsGroove deformation has been analyzed in the literature primarily in terms of classical elasticity theory, which is based on assumptions that are not appropriate for stylus-groove contact. To determine the actual deformation-force relations, complex groove impedances have been measured as a function of tracking force, groove speed, etc. The results obtained are contrasted with classical predictions.Author: White, James V.Affiliation: Acoustics Research Laboratory, Harvard University, Cambridge, MAJAES Volume 18 Issue 5 pp. 497-506; October 1970
Factors Affecting the Needle/Groove Relationship in Phonograph Playback SystemsIt is shown that a phonograph pickup stylus riding in the groove of a record partly penetrates the groove walls because of elastic and plastic deformation of the record material. At high bearing loads complete plastic flow sets in and the needle leaves a permanent indentation track, while at lower loads the elastic deformation is predominant. This leads to amplitude distortion in the reproduced signal which may be of two types: one which is a function of the recorded wavelength (G function or translation loss), the other a function of the dynamic moving mass of the stylus/armature (H function or stylus/groove resonance). A third phenomenon (S function or scanning loss) is caused by the finite size of the stylus/groove-wall contact surface. Experiments with specially built pickups show the evolved theory to be valid even for very high frequencies. Special test records with recorded frequencies up to 100,000 Hz were used for these experiments.Author: Bastiaans, C. R.Affiliation: Westinghouse Research Laboratories, Pittsburgh, PAJAES Volume 15 Issue 4 pp. 389-399; October 1967