I have owned a PrimaLuna ProLogue 4 tube amp, and wouldn't feel comfortable comparing it to the 509X... I mean, it's an $800 tube amp vs a $9500 integrated, so they don't have much in common, but I'll try...
The PL 4 was very smooth sounding and a little rolled off on the highs. It did sound a little chesty in the lower mid-range, compared to the 509X, which absolutely shines in the mid-range (lots of rich, realistic detail in vocals and higher octave bass, plus a lot of grip and control).
But the PL 4 (to me) had much less control over the bass. It was pretty flabby/tube-y and diffuse, if that makes sense. The 509X retains its sonic character pretty much at any volume as well.
Before I bought the 509X, my local dealer is a Parasound and PrimaLuna dealer, so I listened to both the Halo integrated and Dialogue Premium integrateds there for probably 30 minutes each.
Compared to both I prefer the 509X... To me, the Halo integrated didn't sound like anything special. It sounded like a very good stereo system, like something that wouldn't draw me in very much to the music but would be perfectly acceptable to listen to as background or even to show off to friends, etc.
The Dialogue Premium is a very good integrated. In contrast to the Halo, it was very engaging, and did have exceptionally smooth mids, soundfield, depth, and "sparkle" to the high end. But to compare it to the 509X, the Luxman has more dynamics and control. It has better placement in the stereo field of the instruments. More expansive both front and back.
But the biggest thing, above either of the PrimaLunas or Parasound that I compared it to, is the dynamics of the Luxman, especially with my La Scala II speakers. With the 509X, I get a real sense of movement to the music. The dynamics are just stirring, it seems to control the music so well. Certain passages almost seem to be in motion, and it is quiet and delicate and detailed, or massive and almost startling when it needs to be.
All of that combined with the Luxman build quality, brand integrity, and aesthetic of the 509X is why I went with the 509X integrated.
Hope that may have helped some!
The PL 4 was very smooth sounding and a little rolled off on the highs. It did sound a little chesty in the lower mid-range, compared to the 509X, which absolutely shines in the mid-range (lots of rich, realistic detail in vocals and higher octave bass, plus a lot of grip and control).
But the PL 4 (to me) had much less control over the bass. It was pretty flabby/tube-y and diffuse, if that makes sense. The 509X retains its sonic character pretty much at any volume as well.
Before I bought the 509X, my local dealer is a Parasound and PrimaLuna dealer, so I listened to both the Halo integrated and Dialogue Premium integrateds there for probably 30 minutes each.
Compared to both I prefer the 509X... To me, the Halo integrated didn't sound like anything special. It sounded like a very good stereo system, like something that wouldn't draw me in very much to the music but would be perfectly acceptable to listen to as background or even to show off to friends, etc.
The Dialogue Premium is a very good integrated. In contrast to the Halo, it was very engaging, and did have exceptionally smooth mids, soundfield, depth, and "sparkle" to the high end. But to compare it to the 509X, the Luxman has more dynamics and control. It has better placement in the stereo field of the instruments. More expansive both front and back.
But the biggest thing, above either of the PrimaLunas or Parasound that I compared it to, is the dynamics of the Luxman, especially with my La Scala II speakers. With the 509X, I get a real sense of movement to the music. The dynamics are just stirring, it seems to control the music so well. Certain passages almost seem to be in motion, and it is quiet and delicate and detailed, or massive and almost startling when it needs to be.
All of that combined with the Luxman build quality, brand integrity, and aesthetic of the 509X is why I went with the 509X integrated.
Hope that may have helped some!