I just discovered
http://www.milleraudioresearch.com/avtech/index.html Here you can finally find some objective measurements of the current
and selected vintage gear. It is free, but you will have to register.
There is a quite a good representation of analog. I have yet to go trough it all, but what I have seen so far is very well made and above all, all the gear is tested using the same methods and therefore results are comparable.
You will find the measurements quite illuminating. The deviations in frequency response, channel separation, percentages of distortion, speed accuracy, wow, flutter, rumble - may well be shocking to some, if not most. Remember, if the device does not perform as it should have , it CAN NOT sound correct - no matter how you might like it subjectively. You have to bear in mind most manufacturers can not afford the measuring equipment ( or equivalent) used for these measurements - merely ASSUMING that a certain technical solution that should in theory bring better result does not necessarily deliver in practice. Just check the results for the Kuzma Stabi S turntable with a normal single platter and additional double platter, to see what I mean. Yet it is not NEARLY as bad result as some others...
I will try to make at least the most basic measurements on PC so that I can present some graphs etc. Problem is my very limited knowledge in digital, but I know that covering the real frequency response of analog using digital measuring equipment is co$$$$$$$$$$$$$$$$$$$$$$$$$$$$$tly. It requires essentially flat frequency response to 50 kHz and response still going relatively strongly ( WITHOUT brick filter at any frequency ) past 100 kHz. DSD recording can give useable results, yet I am not at present aware of any measuring software using DSD to be used on PCs or Macs. So my first steps will be limited to 20 kHz, in line with standard PCM 44,1kHz/16 bit resolution available.
Please note that I am not going to answer much, if any, questions that might arise from the tests published, such as relation(s) among various measurements and perceiced subjective SQ. It is too complicated and interrelated to be given in a forum - besides that I am pretty certain what is a GO and what is a definitive NO GO, I would like to have solid scientific evidence before sticking my head out.
You have to remember that phono cartridges are extremely difficult to make and even more so to measure properly. Sample to sample variation unfortunately can play a huge role - while I will do EVERYTHING possible to extract the most out of any TT/arm/cart combo, reviewers do not have so much time and by default have to limit themselves to the practices that are reasonably to be expected from general public. In analog turntables, that is azimuth - just see how much does channel separation measurements vary among cartridges. Many of those would benefit greatly from correct azimuth - you simply have to realize that 100% correctly aligned for everything cartridges are rare and therefore very expensive. If you think you have the right to get by default such a cartridge - think of the dimensions involved - and think again if you still feel you should be the lucky guy or gal that always get top 0.00.....1 % of production. Even 5 figure price tag is no guarantee for that. Back in the day, for the celebration of now late Mr. Sugano's 80th birthday, there was a 80th Anniversary Limited Edition of 80 pcs of really outstanding carts that got collected in God only knows how many years of production - PRICE TO BE SET BY THE DEALER, no MSRP whatsoever ! Koetsus are precise devices in ordinary life, I surely would love to hear one of those 80 hors categorie ones - but by now, I guess any real music listener must have worn the stylus on his/hers sample.
Turntables are comparatively large devices and therefore sample to sample variations do not play so big role as in cartridges. Here, performance is easier compared and if so inclined, you can read the objective tests of the units you own or are familiar with - and start building your own "translation from objective to subjective performance" vocabulary. Might save quite a big chunk of money - which can be used for getting more music on vinyl .