It is always nice to conduct a comparison wherein I really enjoy listening to the music over and over again. Back when I did this comparison of the 8th Quartet by the Eder on Naxos and the Emerson on DG, I dragged both CDs around with me for a month or two and listen to them in my car, my van, and at work through the CD-ROM and fairly cheesy Altec Lansing speakers associated with my computer. I also tried to listen to both disks casually on my home system before I got down to really serious listening. This gives me an opportunity to really get the feel of both performances, and believe me, with this much listening, it is great to be comparing disks of music that I truly enjoy. Finally, I forced myself to sit down and compare the two recordings more systematically on my home system. I then pulled together my notes and recollections and sat down at my home computer to peck out my findings.
I began my remarks above by noting how nice it was this time to be listening so much to music that I really enjoy; moreover, it was also nice to discover that my preferences regarding both sound and performance quality favored the same disk. I found that one disk had a slightly more distant perspective but with clearly better midbass and a nice sense of space. This disk also seemed to blend the instruments together better. The other disk sounded OK, and revealed a bit more scraping noise and such (some people love all that detail), but my clear subjective preference was for the warmer, more robust sound of the first disk.
Both in my "casual" listening and in my focused listening, I found that the disk with the warmer sound also seemed to have the more expressive performance. This is not to say that this was a heart-on-sleeve rendition of the music--it is not (in fact, some might criticize it for being too straightforward)--but somehow it seemed to communicate emotions more forcefully than did the competing version. Yes, these differences are subtle, and my judgments about them are certainly subjective in nature, but I could not help but conclude that the first disk contained the more moving and convincing musical interpretation.
Because I found one disk preferable in both sound quality and performance, my preference is clear--the DG recording by the Emerson String Quartet. After auditioning this disk, I really looked forward to picking up the complete Emerson boxed set and comparing it with my Fitzwilliam boxed set. The Naxos disk offers two other quartets, and can serve as a good introduction to the marvelous Shostakovitch quartets, but if you are really serious about the music, I would think that the Emerson set would be a better long-term investment than the complete set on Naxos.