Originally Posted by jaddie
Sorry, I really don't see the point of continuing this discussion if we're going to only speak in generalities with the reference data being an out of print paper being recalled from memory. I also don't see the point of talking about extremes as if they had bearing on the usual and normal. Referencing a world bike speed record has nothing to do with what the average bike rider experiences. Without access to the "Marcrieff Papers", I simply cannot evaluate any hypothesis based on them. I'm not a disciple of his.
Let me take the burden off others and go ahead and discredit myself: I cannot cozy up to anyone who spends time doing such things as subjective reviews of the audible effects of wire. I haven't sipped that Cool-Aid, and I'm not likely to any time soon.
I don't care if a distortion product is harmonically related or not unless the magnitude is also specified. As to manufacturers not publishing IMD specs, I agree they should, but manufacturers have historically published meaningless specifications. For example, "Frequency Response: 10Hz - 20KHz"...means nothing without another figure "+/- XdB". Welcome to marketing 101. But having actually performed all three types of IMD testing on many different devices, I can also say that IMD never exists in isolation of other forms of distortion resulting from non-linearity. If the THD+N figure is vanishingly low, IMD will be there too. And, conversely, you won't measure high IMD without other measurements indicating nonlinear behavior as well. It's simply never an on/off situation.
So, with respect to everyone, I'll have to bow out of the discussion unless some quantitative data is entered into the stated claims. Just stating that IMD exists without any reference to quantitative data or audibility is just alarmist thinking.
OK - will dig out Moncrieff paper, have friend scan it, and send it to you. It is something between 20 to 40 pages IIRC. I only wish THD+N figures (or any other form of non linarities ) for phono cartridges were anything like those in electronics that can be ignored for most part, because they are so low. Even with best cartridges, it is in percent, not tenths or hundrieths of a percent distortion(s) - and although a phono cartridge that has 20 Hz to 70 kHz +/-3 dB or about that tolerance response does exist in real world, it is unfortunately more exception than the rule. I find it surprising for a mastering engineer to even consider equating non linearities of electronics and that of transducers - they are order(s) of magnitude apart.
I never wrote/said anything regarding audio cables. It just happened that the link for IAR had one "cable" in there. BTW, cable IS important in phono equipment, particularly regarding capacitance when MM cartridge is used. And replacing perfectly good "cheap stock" cable with correct electrical parameters for the job with audiophool cable with inapropriate electrical parameters is detrimental and not beneficial to the sound. Replacing with better quality cable WITH APPROPRIATE ELECTRICAL PARAMETERS is OK - and yes, can be heard. But only if and when measurable parameters are the same or very similar to the correct stock cable. One can have the cable out of nonexistium and if it has too high or too low capacitance when used with a MM cartridge, it will sound poor no matter what.
Here the first result for Google picture search " Shure Hyperelliptical vs Micro Ridge" - along Shure's, some other current carts and their frequency responses and THD measurements with pictures of the actual styli:
Please note that all cartridges featured are pretty high quality - all stylus tip profiles are an equivalent of Shibata or better; an elliptical or even conical stylus would have given much worse results still.
I have absolutely no intention discrediting you or your work you obviously did with great devotion , attention to detail and competence. On the contrary, I would simply like you to broaden your understanding of what is going on once past your work with mastering a lacquer disc / stamper process. Here the link for most test records still likely to be "procured" one way or another, with sleeves with description of recorded signals ( including record used from above link):
I can see the results on an oscilloscope and/or make DSD recordings of phono measurements ( DSD at 5,6 MHz will capture most of the results quite correctly, it is essentially flat to past 50 kHz and rolls off gently 6 dB/0ctave above that, much like analog, capable of recording past 100 kHz, has 120 dB dynamic range, about similar channel separation, THD+N & IMD like best electronics, unmeasurable wow & flutter ... in short, DSD recording should be good enough to allow phono measurements to almost the same degree of precision as if measuring the real thing ). If you own or have acces to measuring equipment, needed to do IMD measurements, I can record some samples and send them to you on SD card or similar - DSD at 5,6 MHZ is 11 min audio = 1GB. You would very quickly discover the distortion figures in cartridges are unfortunately not small enough to be neglected - specially if frequency response above 20 kHz is considered. The same goes for scanning loss at high audo frequencies at inner grooves - there is a reason why only CBS STR 100 test record has such test and results can be quite embarassing - try anything from +3 to - 10 dB at 20 kHz as compared with the same cartridge at the outer grooves where usually all the high frequency tests are done. Similarly, only the best cartridges with the best stylus tip geometry will produce anything like same shape of square wave recorded at outer AND inner grooves - CBS STR 112. I have yet to see published result or photo for both outer ( better, usually published ) and inner ( not seen published so far , usually far worse ) groove 1 kHz square wave.
Here the link to my "nearest equivalent" - except he has measuring equipment necessary to provide hard copy, graphs etc :
% of distortion for phono cartridges are hard to quantify,as it is very dependant on the exact test record used, due to geometrical reasons like Vertical/Stylus Rake Angle, etc, etc - but low enough to ignore them are certainly not. Here one link with IMD measurements :
I do own Shure C/PEK 3 Cartridge analyzer - NOS, but it is still at my friend's in the USA and I will have trouble importing it to Europe due to lack of CE certificate - it predates EU as we know it now for all practical purposes, but for customer officer all that is needed to see is US power plug for the game to be over. Will have somehow to get it here ASAP - one way is to declare it as vintage museum piece - not far from the fact, given the world today is predominantely digital...
I hope it is evident to everybody from this post my intentions are good - in no way I intend to discredit anybody who has honestly contributed to the cause of better recording or reproduction of the sound - and specially not you, who have kindly shared your knowledge regarding analog mastering and azimuth in particular. It is just the fact I can not pull the magnitude or % of distortion from thin air due to (temporary) lack of measuring equipment - but if it is visible on the scope with naked eye, it can not be low enough to ignore.
The links giving at least sneak preview to the magnitude of distortion in phono cartridges posted were obtained using Google search (pictures) and although I am familiar with some of them for some time now, I am in no way affiliated with them. The IMD distortion from 1 to 50 kHz result is nowhere to be found - as indicated in one of my previous posts, CBS CTC 310 test record LP with which it is possible to measure it did not even "exist" on Google prior to my postings. Same on Yahoo, etc. There are posts regarding the CBS CTC 300 test record LP from the same series used for trackability testing in Steve Hoffman's http://forums.stevehoffman.tv/threads/ortofon-540-phono-cartridge-review.91096/ - other than that, the last series of test records issued by CBS CTC "never happened". Yet the creators of this last series did know exactly what they were doing - the time this series of test LP records appeared coincides with the greatest rage for CD - the plug was pulled for analog and the whole of CBS CTC not long after.