Much better MM cartridge than Shure V15 IV?

Phasecorrect, thanks for affirming my choices so far. Clean vinyl ....yum!

Your point about subs interests me. The matching LS3/5a bass units sit underneath each speaker and act as a speaker stand. As far as I understand the specs, they dig about 20HZ deeper than the speakers alone, down to 50HZ max. Is that a very light addition to the bass response of my speakers? The cost is quite high: $1500 to have the units purchased and shipped to the USA. Does that seem like money well spent? Phono amp a better idea?
Thanks

I'm not familiar with that product...but 1500 will buy you a very good dedicated sub with greater bass performance...rel, velodyne,etc...however if u don't listen to bass dominant material...be aware a goof sub will offer very subtle improvements

Respectfully disagree with Pasecorrect's otherwise good advise, re the addition of a good sub. A properly integrated sub will retrieve hall information/ambience in good orchestral recordings now missing due to your main speakers' limited bottom end extension; even if the recordings are not "bass dominant". It will also (partly as a result of the new-found hall info) improve imaging. The LS3/5a's are a perfect candidate for use with a sub such as a REL Strata. IMO , the improvement will be anything but subtle.

That's fine...Sumaato will have to ultimately decide...most musical reproduction is midrange reproduction which the ls 3/5s Excel at...I ended up selling my sub...but my mains at the time went lower than 3/5s...so I didn't gain/miss much...miles do very...some swear by subs...others not so much...worth a try though

Good to hear all these viewpoints. I take Frogman's point about hall ambience being well developed by the addition of a sub...that was my (theoretical) understanding too. That's a clear direction to go in and I plan to pursue it. Bruckner needs all the help he can get.

The cartridge choice is an issue still. I remember a few years back, at one of the high-end exhibitor rooms at the Rocky Mountain Audio Fest in Denver; I was listening to a good turntable, with two identical arms mounted on it, each carrying a different MC cartridge. The quality difference in how they each rendered the music was dramatic and clearly related to price. That observation is what stimulated my original question about upping my cartridge quality. But within the domain of reasonably decent MM cartridges do you think perhaps the range of quality is narrower?