I tried these strings on my relatively bright Stradivarius pattern cello from the 1950's. The previous strings were tungsten Spirocore on C, G and Larsen Magnacore on A, D. After fitting a whole set of Il Cannone Direct & Focused I noticed that the lower strings sounded much more focused, but not brighter. The core sound also became more pronounced. This was definitely an upgrade for my cello, both in arco and pizzicato.
The D string also sounded more focused and had a more brilliant touch to it. The A string, however, sounded significantly weaker compared to medium tension Magnacore and also throttled when pushed! I then tried the "Warm and broad" version of the A string and this worked out much better. Compared to D&F, this string produced longer enduring resonance, and, most importantly, no throttling problems. However, the Magnacore, although more unruly and not as smooth sounding, was significantly more powerful than either of the Il Cannone models, and projects significantly better on my cello.
My impression is that the D&F set is basically Larsen's version of Evah Pirazzi. I never liked the latter due to their relatively weak core sound, but I do like the Il Cannones with their very pronounced core. I just wished the A-string packed a bit more punch. In summary, for my cello, D&F on C, G, D and W&B on A worked very well together, adding warmth at the cost of clarity. I was surprised at how large this effect was, so much that I would not go for substituting another D&F string with W&B as I predict it would simply sound too muddled and fuzzy on my instrument.
