Hi all,
First, sorry for writing in English, it is a bit easier that doing it in Danish:). If you'd like to contribute to the discussion (if there is any) please feel free to do so in Danish, google translate does wonders:).
I've been an owner of the AV S3 (not Si3) basic model for some months now. Some doubts about its sound quality have been piling up so I did some measurements. I tried first the Audiovector forum but that place is far from being lively and it seems that the AV stuff state that they avoid talking about graphs as the interpretation can be misleading so no response from them to my post. The hifi4all forum seems to be a much better place for a discussion:).
My initial complaint was about the treble and bass, or lack thereof. In general, the sound at normal listening level (I erroneously played things quite loud in the store where I was listening to speakers) lacks punch, is laid back, lacking details. It seems that there is too much mid range. The rest of the equipment is Cambridge Audio 550A amplifier, Thule CD150B CD player, non branded speaker cables (2m long, quite thick). The listening room was, at the time, around 8.3x4.3m. The intention was to divide the room and I didn't go for measurements before that was done. Now that the listening room is around 5.3x4.3m I did some measurements. I will here combine my two post on the measurement that I had posted on the AV forum.
The room is 4.3x5.3x2.5m. The distance between the speakers is around
2.5m, the listening distance from the mid point is around 4m, the toe in
is around 4deg. The distance from the wall to the front of the speakers
is 65cm (and can't be increased). The microphone (half inch pressure
field) and the mic power supply are B&K, I would need to see the
exact models if anyone is interested. WInMLS was used for the response
measurement, the stimulus was a sine sweep. The measurement was not
super precise but I believe it is good enough to point to any obvious
problems. The magnitude responses of the right and the left speaker are at:
Audiovector S3 room response.
The
graphs are smoothed in 1/6octave bands. At low frequencies I can see
mainly room modes as measured in the listening position, but it seems to
me that there is not much output below 60Hz. Do not know how to
interpret the mid and upper mid frequencies due to room interference,
but it seems that there is a dip at around 3kHz in the speaker response.
In my original post I complained about lack of details in the highs,
actually as if the highs are missing quantity wise. My measurement shows
that the tweeter starts to roll off already after 12kHz. It is the same
on both speakers so it is unlikely that it is a malfunction.
The measurement results in a reverberant environment are always tricky
to interpret due to room interference, especially at low frequencies
where the room modes can be separated. So even if you inject a small
amount of energy you may measure fairly high sound level, depending on
the speaker and the microphone positions. This may be the case with the
peak at around 35Hz in my measurements. However, at the highs there are
many room modes, making the field more diffuse-like. In my room this
happens after around 300Hz. That's why it is easy to see the speaker
upper cut off even in the reverberant environment, as there is nothing
to support the speaker acoustical output once it starts rolling off.
Seeing that this starts already after 12kHz is not quite satisfying.
When
I listened to the speakers in the store I noticed they were on the
darker side. But I listened to them at a fairly loud level, not quite
suitable for home listening, so I could hear more details. But, by
seeing what I am seeing in the measurement I lost confidence that I can
get a decent quality boost by changing any part of the equipment apart
from the speakers themselves. And that was not the intention when I
bought them

So,
I believe I found some explanation in the measurement for missing
involvement with music. It is mainly not quite deep bass (I'd expect
more considering the cabinet size) and somewhat lacking treble.
I'd like to hear the experience of other Audiovector users. S3 and S3 super share the same tweeter so the treble should be pretty much the same in the two models. Thanks.