I own the Helicon 800 as a recent purchase. Mine are not burned in more than 20 hours. I have been told they take at least 100 or 200 hours, during which time there are continual changes, driver to driver.
Thus far, the Helicon 800 does many things well. They have a big sound but are not pumped up sounding or forward. They have a big soundstage that is not exaggerated, but well spread out, airy, and sort out detail superbly and in a natural manner. They are capable of playing quite loudly without stress or overload. The bass so far is very good, but I have heard even better. Voices and piano are very believeable and reproduced very well, without being pushed in your face. So, I would not call the Dali midrange forward.
I do believe that cables have a big effect on sonics in general, especially as you go up to higher end components. Thus far, the Helicon has sounded different with different cables. Some cables will provide a much better bass, a more present or more recessed midrange, and a brighter or less bright treble. Perhaps the ribbons will continue to change as they burn in, but I have a feeling that they give a transparent windowpane to the upper end. If the cables are bright, you'll get brightness. If the recording is bright, you'll hear it. Speakers with tweeters that have less extension and detail will probably be easier on the ear with bright and poor recordings, but they will have less detail and air. It's a matter of how you hear and what musical material you listen to.
Similarly, an amp with a hot high end is not a good match. I am using tube preamps with a Pass amplifier. The reason people really like tube amps with Dali speakers is that tube amps will give a less extended high end that is smoother, and this will be more complimentary to the tweeters. That said, I like my Pass amp on these speakers 90% of the time. Obviously, an overetched or bright digital player will probably not bring good results. There are many good sounding CD players and DACs out there, so I think anyone buying equipment at the level of the Dali will have digital units that have good treble response, not bright, grainy or unnatural. However, there will still be players that have a better synergistic match than others.
Again, keep in mind that I am basing these comments on a speaker that is still in the burn-in process.
Thus far, the Helicon 800 does many things well. They have a big sound but are not pumped up sounding or forward. They have a big soundstage that is not exaggerated, but well spread out, airy, and sort out detail superbly and in a natural manner. They are capable of playing quite loudly without stress or overload. The bass so far is very good, but I have heard even better. Voices and piano are very believeable and reproduced very well, without being pushed in your face. So, I would not call the Dali midrange forward.
I do believe that cables have a big effect on sonics in general, especially as you go up to higher end components. Thus far, the Helicon has sounded different with different cables. Some cables will provide a much better bass, a more present or more recessed midrange, and a brighter or less bright treble. Perhaps the ribbons will continue to change as they burn in, but I have a feeling that they give a transparent windowpane to the upper end. If the cables are bright, you'll get brightness. If the recording is bright, you'll hear it. Speakers with tweeters that have less extension and detail will probably be easier on the ear with bright and poor recordings, but they will have less detail and air. It's a matter of how you hear and what musical material you listen to.
Similarly, an amp with a hot high end is not a good match. I am using tube preamps with a Pass amplifier. The reason people really like tube amps with Dali speakers is that tube amps will give a less extended high end that is smoother, and this will be more complimentary to the tweeters. That said, I like my Pass amp on these speakers 90% of the time. Obviously, an overetched or bright digital player will probably not bring good results. There are many good sounding CD players and DACs out there, so I think anyone buying equipment at the level of the Dali will have digital units that have good treble response, not bright, grainy or unnatural. However, there will still be players that have a better synergistic match than others.
Again, keep in mind that I am basing these comments on a speaker that is still in the burn-in process.