 |
 |
|
|
 |
|
 |
|
1. Low loss design
When listening to a piece of music, the recording contains a blend of the sound from the instruments and voices themselves, and the reflections from the room in which the recording was made (or the room effects added in the recording studio). Your senses use these reflected signals to obtain information about the size of the room in which the recording was made, thereby creating the illusion that you are listening to the music in the same room that the musicians were originally playing. These reflected room signals are very low in level and any distortion or lack of detail will mask or remove them. The result is a sound that is flat and two-dimensional and tends to stay inside the speaker box.
So, how can we secure the reproduction of details while also designing a speaker that is clean and does not resonate? When designing a drive unit, the easiest way to deal with resonance - and peaks and dips in the response - is to dampen all moving parts so that they do not resonate themselves.
However, by doing so, chances are that low level room reflection signals will be reduced or completely taken out in the process, thus removing the very signals that are needed for you to recreate the dimensions of the original recording room. In order to design the unit so that it has flat response and does not resonate, while at the same time being able to reproduce detail, solid know-how in dealing with mechanical properties in drive unit design is needed.
In all Vifa drive units, more than seven decades of experience has been applied to the design of low loss properties in all moving parts. The result is a drive unit design that combines flat frequency response and low distortion with excellent reproduction of detail. You can feel it for yourself by carefully pressing your finger on the surround and then seeing how fast it responds when you move your finger. Overdampened surrounds tend to feel like sticky rubber and react slow to changes. This is one reason why they are not fast enough to reproduce low level detail.
2. Low compression
Air behind the moving diaphragm acts as an air spring and reduces control over diaphragm movement. This is particularly important when it comes to the reproduction of detail, so by ensuring that air compression is kept low, the reproduction of detail and room information is improved thereby opening up the sound stage. Keeping air compression low is accomplished in several ways.
In our woofers, the basket itself is designed with low air compression in mind. By opening up the rear of the chassis, air compression is minimized and the rear of the cone is allowed to couple efficiently to the air inside the cabinet. In addition, the cone area behind the dust cap and the spiders are all vented. In our tweeters, the voice coil is vented and the geometry of the rear chamber is designed to minimize air compression. Furthermore, the connection between the dome and the rear chamber is tuned by the use of special dampening materials and openings.
3. Linear magnet flux in the voice coil gab and low motor distortion
A common problem with voice coils is distortion caused by high self-induction and impedance varying with excursion. To avoid this, all Vifa drive units utilize a copper or aluminium short circuiting part in the pole piece. This technique especially reduces 2nd and 3rd harmonic distortion and improves clarity throughout the frequency range of the drive unit. Even in our tweeters, a copper cap design is utilized for the same purpose.
Back to top
|
|
 |
| |
|
|
|
|
|
