Any advice on buying quality vinyl

Those tube based recordings from the golden age of stereo are incredibly lifelike, no argument there. Less (technology) was more. But the mastering equipment had a limited frequency range, so records made in those days could not approach the sonic quality of the master tape. This gap narrowed considerably in 1968, when Neumann introduced a new disc cutting lathe (the SX-68) able to reproduce up to 20kHz. Unfortunately recording technology also changed drastically with the introduction of solid state multitracking (and multimiking). More (technology) became less.

According to your information RCA’s Dynagroove system was tailored to low end systems with spherical tips, just when elliptical tips were becoming more mainstream (the 60’s was a spherical world). This does indeed suggest they bended over to their marketing division. Dynaflex was the thin icing on the cake.

As for those supposedly noisy early LSC’s, I decided to do a little experiment. I remembered I have two pressings of one of their sonic spectaculars: the complete Albeniz Iberia from 1961, conducted by Jean Morel. I have both the LSC 6094 shaded dog (Indy pressing with 1S,1S,1S,3S lacquers) and the SB-2131/32 (3D,2D,2D,3D lacquers) mastered and pressed by UK Decca, who had a licensing agreement with RCA. Both copies are near mint condition, they both went through the same cleaning procedure and were both played with a Transfiguration Proteus MC cartridge. The experiment showed that both pressings have completely silent backgrounds. Sonically they were very close as well, but I’d give the edge to the LSC. It has slightly more dynamic range and is definitely more controlled in the loudest tutti passages.

What would be responsible for the difference: better tape source, better mastering or perhaps better vinyl?

In my experience all records sound a little better with each subsequent cleaning, even after three or four times. I use Okki Nokki machine and Audio Intelligent fluids, pre-cleaner plus three step solutions. 

@edgewear,

Nice experiment. To be very candid, I am at the edge of my competency now. Of the three choices. I have heard that back in those days, 2nd gen copies, used for mastering, would be flown to other pressing sites so that rules out tape source? I would guess that better mastering, which includes both the equipment and the person behind the console and running the lathe. As far as I can tell from cruising Steve Hoffman's forums, he talks about a "breathe of life" (tonality) in the early shaded dog Living Stereos. I can't seem to find, in these same forums, a strong reason for that difference. 

As good as the sonics are, I still struggle to get one's that run quietly. I guess it's just the lot I run into, rather than the quality of the vinyl or the poor aging of the vinyl. 

I still struggle to understand why recently opened, 60-year-old copies that show no signs of moisture damage, mold, or excessive heat would play with a low-level running noise. It's not my system. I play other LP's all the time that run CD quiet.

Maybe I need to find a stylus that rides higher in the groove....

Interestingly, to me anyway, I read somewhere that some labels including RCA are no longer flying or shipping original master tapes overseas- they are just too valuable. So either the lacquers have to be cut stateside or they are sending digital masters. The latter is what I heard was being done. That might also explain any difference people are hearing in newer audiophile (re) releases?

@voiceofvinyl,

I certainly don't have all the facts, but apparently the industry practice was either to send lacquers to foreign markets (used on location to press the discs) or to send second generation copies of the master tape and have the mastering done over there (usually under some licensing agreement). Even in those days it seems that record companies were reluctant to ship around their original master tapes. This might explain why original pressings made in the home country of the record company usually sound best. And also why in the above comparison of the Albeniz the US pressed LSC sounds slightly better than the UK pressed SB. 

But to complicate matters the agreement between RCA and Decca also involved recording. Many of RCA's recordings made in Europe (mostly with London orchestras or the VPO in Vienna) were made by Decca recording engineers like Kenneth Wilkinson. Obviously Decca did the mastering and pressing of the UK issues of these recordings, but did they also use the master tapes (which they made themselves)? I have no idea.

So I did another experiment: Berlioz' Symphonie Fantastique by the VPO conducted by Pierre Monteux and recorded by Decca. In this case the UK pressed SB-2090 (1M,2L lacquers) sounds better than the US pressed LSC-2362 (2S,4S lacquers). This outcome suggests that Decca had access to the original tapes, but of course as legal owners so did RCA.

I admit to speculation here, but IF both companies used the original tapes for making these records, the Decca mastering engineers had the edge over their US collegues. But perhaps this is totally wrong. Perhaps a 1S/1S copy of the LSC sounds best of all, who knows?

So there's really only one way to find out: listen for yourself! That's just the advise you were waiting for, right? ;-).