I would generally agree with Axelwal: the UK-pressed DGs are inferior to the German ones (sound less full and detailed, higher incidence of pressing faults). I think, however, that if you go back as far as the beginning of the 1970s, the UK pressings were sometimes up to the level of the German ones. I have a box from the 1970 Beethoven Edition (Volume 7 - violin sonatas, cello sonatas): the records are UK-pressed, they are quiet and have very good (valve-like) sound. I have second copies of a few of these records: these are later German pressings and the sound, though perhaps a little more immediate, is not significantly better.
Whatever the quality of the final product, it seems that the UK records were pressed with DG metal stampers sent from Germany. So any differences are presumably to be attributed to the quality of the vinyl, the degree of care exercised in the pressing process and the length of the pressing run using the same stamper (more on this below).
Interestingly, the 1970 Beethoven Edition came out in the UK with the tulip label, while the continental pressings (issued at the same time) had the later DG label.
Apparently not all non-German pressings of DG material are to be despised. I was in a record shop in Athens (of all places)some months ago and they had a special bin dedicated to French-pressed DGs. I quizzed them about this and they said that in their opinion these have the best sound of all. Why? More limited pressing runs (in Germany DG was pressing for the extensive home market and also for many foreign markets). I do not have a sufficient number of these records to make any comparison, but I suspect that the difference (if it exists in a significant number of cases) will not be great.
What I would like to know is why - irrespective of where they were pressed - DG records so frequently have poor or very mediocre sound (it is well known for instance that the Amadeus Quartet, despite being DGs premier string quartet throughout the stereo period, was hardly ever given anything more than mediocre sound) . Was conservative mastering to blame? One might think this, given that some DG record sides (those with short programme content - say 10 -12 minutes) have very wide dead wax areas, i.e. the music grooves are bunched together in the first centimeters of the disk, suggesting that nobody in the disc-cutting team had thought of spreading the grooves out and thus realising a more powerful cut. But in fact it may be wrong to blame the cutting engineers; the problem may well have been with master tapes themselves. When (a few years ago) the Drolc Quartet recordings of the Reger quartets were reissued on CD, the reviewer in Classical Record Collector made a point of commenting on the mediocre sound. Presumably DG had gone back to the original masters!
