Svar fra en Violon eier i Australia:
Here in a nutshell is a summary of the strengths and weaknesses of both speakers (Violon vs. Avantgarde Duo):
Integration - both speakers have problems with integration, but the nature is different. The Avantgarde has the two horns spread widely apart and the sound does not come together unless you are sitting far away from them. I found that 3m is the minimum distance, but the soundstage was still too large. 4m was much better. You can actually hear each horn as a seperate driver if you sit too close. The Avantgarde also had problems integrating the active woofer section with the passive horns above it. When I heard the Duo's, the dealer could not find a setting where the woofer integrated seamlessly with the midrange and treble horns. On some pieces of music it sounded OK, but on others it was either too bloated or too lean. When I heard the Uno (in a much larger room) the integration was much better. You will have to play with the crossover frequency, level, and phase until you are happy. Because of the Uno, I believe that good integration is possible - but you will always hear the woofer as a seperate source.
The Violons are different. The dispersion characteristics of each of the three different speaker technologies are very well married - you will hear a sound that sounds as if it is emanating from a single source (albeit not as well localized as a good bookshelf speaker or a Quad electrostatic). However, the Violons have a different problem - the tweeter is insanely good, the midrange very nearly as good, but the woofer section lets it down. One look at the crossover settings will tell you why - woofer 30Hz - 800Hz (5 octaves), midrange horn 800Hz-5000Hz (3 octaves), and treble 5kHz-40kHz (3 octaves). In other words, the lowest quality driver is asked to handle the widest frequency range - 5 octaves for the woofer. Crucially, this involves the lower midrange and all of the bass.
The result: on some recordings (mainly recordings which are mostly midrange and treble) the sound from the Violons is to die for. But when you crank the volume, or play a large scale work with a lot of bass, you can hear the woofer section noticably slow down and get coloured while the mid and top ends remain pristine.
So in summary - the Avantgardes will not integrate unless they have a large room. The Violons will not integrate if given a complex large scale recording at high volume. One has problems with driver integration and coherence (Avantgarde), the other has problems with speed. These problems are unique to the Avantgarde and Violon, it is rare to find a conventional box speaker with the same problems.
Tonal balance. To my ears the Avantgarde sound definitely exhibits horn coloration. I also found that the degree of coloration depends on the amplifier used. I heard the Uno's first with an Audio Note Oto SE (8W SET) amp. The coloration was simply terrible, and I cut short my audition because I did not want to waste the dealer's time. He then offered to use a Graaf OTL. 30 minutes of warm-up later, the sound was MASSIVELY improved - the sound was less coloured, and sounded more "normal". However, it was still laid back and lacked a lot of treble detail. I heard the same when I auditioned the Avantgarde Duo with my Cary CAD-805AE amps.
The Violons are a more clinical speaker. Compared to the easy and warm sound of the ProAc's, the Violon has more of a sound that lets you analyze deep into the music and let you hear exactly what everyone is doing. However, you may not always be in the mood for this and the Violons definitely have a less enjoyable sound than the ProAc's. If I can put it this way - the Violon is more of an intellectual experience, the ProAc's more of an emotional experience.
To my ears, the horn coloration of the Avantgardes would have always gotten in the way of the music, because it is so distinctive. The Acapella has no such coloration but its tonal balance is different.
Imaging. Don't care too much about imaging, but i'll say this. The Violon is more forward, the Avantgardes succeed in projecting more depth. In the right room, the imaging ability of the Violon is outstanding. It is better at creating and placing musicians in a 3D space. Excellent for small ensembles. The Avantgardes place you further back, but sounds more realistic as a result. Excellent for orchestral works.
Dynamics. Once again, very different between each speaker. The microdynamics on the Violon are exceptional. I have heard many speakers through my travels, and NONE of them will come close to reproducing the effortless midrange and treble microdynamics. Macrodynamics are slightly disappointing - a loud crescendo does not build up with the same drama that you will get with an Avantgarde (or even some of the other Aussie speakers - Osborn, Aslan, and SGR). The Avantgardes will really scare you with the dynamic contrasts - pianissimo is pianissimo, and fortissimo will make you fall off the listening chair. The Avantgardes can go really loud seemingly out of nowhere, and it goes loud so cleanly and so effortlessly. This is the major strength of the Avantgardes. Very few setups I have heard can match the effortless dynamics of these speakers.
Amplification. The Avantgardes can live with a flea powered SET. But as pointed out above - you want a VERY GOOD SET that will match well with the speaker. Even the Audio Note Oto, which theoretically has enough power, sounded terrible.
The Violons like to have power. At the moment I give them 110W of Class A triode power, but it's not enough to control the woofer as well as I would like. If you buy this speaker, you will run into the same problem asked by many Acapella owners around the world - what is the best amplifier for these things? Do you get a beefy solid state amp but trade away the top end, which will become more clinical? Or do you get a high powered valve amp and live with flabby and inadequate bass? Take a look at the other systems on AudioGon, and you can see a number of different approaches to the problem. Note that Acapella themselves like to demonstrate the Violon with Einstein OTL. I have never heard this combination but I would like to try.
... in short, with both speakers you will have to compromise. Choose which set of compromises is more right for you.