I have listed to a number of 'Pro' Devialet's now, and my feeling is that there is very little difference between the presentation of vocals between the old 'Expert' and Pro models.
So I am more or less with Pim on this one. It makes sense that you are finding a difference in the bass performance. The LS50's do have a reputation for being a little power hungry and the jump from 120 to 220 Pro is almost certainly giving you a lot more of something in the lower frequencies. Therefore, I think the issue might be the very real change in the presentation of the bass causing a negative perception with the presentation of the vocals. There is much you can try here. The LS50's do have a reputation for being sensitive to placement, so you could possibly try positioning further away from walls / corners. (or nearer as an experiment) As others have mentioned, you could set SAM to 0%, or try turning SAM off. In addition, it is possible to 'tune' the bass ports on the LS50's, with the selection of foam inserts KEF provide with the speakers. One easy thing to try, you could simply experiment with gradually turning the bass down via the Devialet tone control, and see if the vocal presentation comes back to life.
So I am more or less with Pim on this one. It makes sense that you are finding a difference in the bass performance. The LS50's do have a reputation for being a little power hungry and the jump from 120 to 220 Pro is almost certainly giving you a lot more of something in the lower frequencies. Therefore, I think the issue might be the very real change in the presentation of the bass causing a negative perception with the presentation of the vocals. There is much you can try here. The LS50's do have a reputation for being sensitive to placement, so you could possibly try positioning further away from walls / corners. (or nearer as an experiment) As others have mentioned, you could set SAM to 0%, or try turning SAM off. In addition, it is possible to 'tune' the bass ports on the LS50's, with the selection of foam inserts KEF provide with the speakers. One easy thing to try, you could simply experiment with gradually turning the bass down via the Devialet tone control, and see if the vocal presentation comes back to life.
1000 Pro - KEF Blade - iFi Zen Stream - Mutec REF10 - MC3+USB - Pro-Ject Signature 12
