There are certainly examples of both analog vinyl and digital CD that seem to sound better to a listener or listeners. In theory digital is technically superior, but in practice too much variability has resulted from decisions made by the person who masters the recording for an easy and clear choice. I'm on the side that likes the CD better, but I am still occasionally surprised at how good a vinyl record can sound.
Back to my original question: Who has actually spent time and effort comparing the sounds of different phono pickups? From the lack of positive answers, I'm ready to conclude that few (if any) people have done it. Many more people have done comparisons among speakers but not phono pickups.
All this leads to a final conclusion. In theory, different energy transducers (pickups and speakers) can make big differences in sound quality. In practice, there is too little evidence to support any conclusions about phono pickups. But, we can easily agree that different speakers do make a big difference.
I've always thought that digital recordings and CDs are nice because they eliminate the possible variations that come during vinyl playback. The variations that may exist among DACs are miniscule. I've done that comparison enough to satisfy myself.
Sorry for not getting back to this sooner.
In another post I addressed some of the reasons an LP might sound better than the later CD version. So I will paste this here.
Your issue of the CD being worse than the LP can happen. The problems are many. It depends which tape master was archived. Was it the original first edited master from the original sessions, or is it the master for the cutting lathe? If the latter there will be a problem. Next tapes deteriorate over time, some brands worse than others. Ampex tapes used extensively for US recordings have been a particular problem in this regard. Whereas EMITAPE used by the European EMI group seems to have very long legs as does German BASF.
Then we get the issue of how well the tape machine to play back the tape master for CD is set up. There are now far too few people who know how to do this properly.
RCA recordings have a particular problem. RCA used a proprietary tape equalization constants. These have been lost and dumped into the demo barge on the Delaware river, when their old headquarters was demolished. So they are played back with NAB Eq usually which is not quite correct. I have some CDs from RCA masters and you can tell the playback equalization is a little off so they play back hot and do not sound as good as the original LP pressings.
When Robert Fines widow, Wilma Cozart, had a tape machine specially built in Japan to do the CD and SACD transfers of the Mercury Living Presence recordings. She was in her nineties when she did this, and did a fabulous job. Most don't take nearly that much care.
As far as A/B cartridges unless you have several turntables that is difficult. You have to change cartridges which is risky, and then set up the whole turntable each time you change.
I do have multiple cartridges. However I actually only use the Shure V15 xmr cartridges most of the time. I do use my
Decca ffss. These cartridges have no cantilever. They are variable reluctance with a diamond at the end of an iron rod suspended by a nylon thread embedded in coils between the poles of a powerful magnet. The delicacy of these and the later Decca London cartridges is legendary. They make for detailed transparent reproduction. However the Shure wins in trackability because of its compliance. The Decca will turn in a superb performance with the right recording. The Shures will play most recordings best and not loose it in heavy modulation, especially on the inside grooves.
Now my SME series III arms have the headshell and carrying arm as one unit. So if you have multiple carrying arms as I do, then you do not have to remount the cartridge. However you do have to reset up as the cartridges are different weights and lengths.
Deeca London Gold Mk IV
View of cartridge in SME series III carrying arm.
That is a 2K cartridge I got for nothing. When I bought my Thorens TD 125 Mk II not working and fixed it, I bought another SME series III of an eBay seller. He had that Decca Gold and wanted to know if he could include it, as he did not know if it was any good! I said yes, please.
I used it for some time on that turntable. That is how you stretch your dollars.
However good as they can sound on the right LP, I bought another Shure V15 xmr NOS on eBay.
I do have a couple of moving coils, a Goldring and an Orfofon, but don't use them as in addition to doing another set up, I have to change the phono preamp module in the Quad 34 preamp.
Basically whenever I get the urge to change a cartridge I always end up coming back to the Shure V 15 xmr, which never fail to get the best out of the most difficult to track recordings. In essence those cartridges make least fuss with total absence of temperament, which is why I rate them the greatest pickup cartridges of all time totally irrespective of price. That made them at $500 a pop the best value for the dollar also.