Best Sounding Opera CD

Try this on vinyl:
Turandot with Sutherland, Pavarotti, Caballe, Ghiaurov, Krause, Pears. Conducted by Mehta. On London records.
One of the best recordings I have heard.

I second Turandot (Mehta et al) on London. It is absolutely fantastic musically and sonically. Among the best opera recordings in my book!

One can't really wrong with the London/Decca labels, (depending on what singers one prefers).
EMI recordings appear to me to be a more edgy/toppy than the equivalent recordings on other labels such as the excellent London/Decca label (owned I think by Universal with also own DG now also)?.
Here are just a few I think well recorded opera cd's that I own and get great enjoyment out of;

Rossini-Il Barbiere In Seville (Cobos Lopez) Teldec
Rossini- La Cenerentola Teldec (Rizzi) Teldec
Rossini-L'italiana In Algeri (Cobos Lopez) Teldec
Wagner Complete Ring-Sawallisch (EMI)
Tosca ( Bocelli)Decca
Puccini-Turandot (Mehta) RCA
Verdi- Luisa Miller (Decca)
Gluck- Ordeo Ed Euridice (Decca)
Humperdinck-Hansel & Gretel (Decca)
Verdi-La Traviata (Caballe/Bergonzi) RCA Fantastic!
Verdi-Otello (price/Cossuto/Solti) Decca
Handel-Alcina -(Fleming) Erato
Massenet-Thais (Fleming) Decca
Samson & Dalila (Cura/Sir Colin Davis) Erato
Verdi-La Traviata (Rizzi) Teldec
Verdi-Rigoletto (Guilini) DG
Verdi-Rigoletto (Merrill/Bjorling/Tozzi) RCA
Verdi-Il Trovatore (Guilini) DG
Mozart-La Clemenza di Tito (Bartoli) L'oiseau-Lyre
Not forgetting most of Big P/Freni on the London label.

A couple of oldie but goodies;
Puccini-Tosca (Caniglia/Gigli) EMI/DRM
Puccini- Madame Butterfly (Scotto/Bergonzi)EMI

I am not an opera buff by any stretch of the imagination, just an officianado of the genre.