Classical music recordings upgrade

I have Beethoven's 9 symphonies by CSO with Solti at the helm on London recordings. Great performance, dreadful analog to digial transfer. Need suggestions for better recordings of this material. CSO is my favorite, but will listen to other orchestras. Thanks.
The London LP box set is fairly common, just make sure you get british pressings. The sound is very good.
Abbado with Berlin is always good, Harnoncourt with European Chamber Orchestra is brilliant for modern recordings. Reiner/ Chicago you cannot go wrong with. And IMO, the best is Furtwangler with Vienna(?) live at the Salzburg festival but you'll have to deal with the recording quality.
For complete sets:

Barenboim, Berlin Staatskapelle on Teldec, the 1963 Karjan cycle on DG, the Bohm cycle on DG, and the Wand set on RCA are my favorites.
I concur with Barenboim's set on Teldec with the Staatskapelle. Absolutely amazing from 1-9 interpretively and sonically. The orchestra sounds great to boot.
For sets,don't overlook Leonard Bernstein - his Beethoven is surprisingly good! I also second the recommendation of Harnoncourt and Wand for 3 divergent views of how Beethoven can be performed.
Celtic66, can you play vinyl? If so, the Solti/CSO performance has been reissued on vinyl by Speakers Corner in beautiful analog sound.
Many of my favorite recorded performances of Beethoven’s symphonies are by conductors who never recorded the whole cycle.

I’ll limit myself to mentioning only one: Carlos Kleiber. His recordings of the 5th & 7th symphonies, Vienna Philharmonic (DGG), are stupendous. He recorded the 4th live with the Bavarian Radio Orchestra (Orfeo, may be hard to find) and it is also a trully great performance.

The Solti/Chicago (I do agree that the London LPs sound better than the CDs) and Karajan/Berlin (the cycle from the 70s, DGG) are, for me, the most satisfying “complete” modern cycles. Conductor, Wilhem Furtwangler (with various orchestras), is one of my favorites of the “old guard” for his personal and unique way with these works, but you'll have to settle for (sometimes) less-than satisfactory sound reproduction. Really a small price to pay for what you receive emotionally.

An interesting, and totally outrageous view of the symphonies by Roger Norrington (Angel) was recorded during the musicologically-correct epoch of the 1980s & 90s, when cats ran for their lives to avoid having their digestive plumbing used for violin strings. I still own it on LPs—it was issued also on CDs—and merits a hearing now-and-then for the panache and lack of religious reverence that, many times, afflicts performances of these works.

There are even complete cycles by “pianists” (the Liszt transcriptions). A recording of the 5th symphony by Glenn Gould is quite good.

Anyway, good luck with your search and best wishes.
Has anyone heard the Naxos box set (Edlinger/Zagrab P.O.)? For 33 bucks, I wondered how those performances and recordings compare to some of these previously mentioned classics. BTW, I personally cannot tolerate the Bernstein recordings unless played in mono.
Gabbro, are you refering to Bernstein’s CBS, New York Phil. cycle or the one on DGG with the Vienna Phil.?
Gabbro, Then try the VPO if you want better sound, its pretty good even for DG. The performances vary from the NYPO version some but IMHO its a wash as to which is better in the overall.
It's a shame that the intensity of many of Bernstein's NY performances were sabotaged by the incredibly crappy-sounding productions. Was someone really listening in the control booth?

It has always baffled me that the artists themselves were not equally horrified by the sound of their LPs. Or, were they, and no one at the label listened to them?
Speaking of the complete Beethoven cycle, today I aquired the Solti/CSO set (London/Decca 70-5667), box in OK condition, LP's in very good shape including the booklet. Once they are run through the RCM and put in new sleeves, I'm looking forward to listening to all 18 sides in order.
Per Vvrinc: Norrington's NEW set on Hanssler Classic also ranks up there with the best. It still has the HIP sound, but MUCH better played and conducted than his earlier set (which is still available on Virgin Classics). That's definitely worth hearing!