help Help / F.A.Q.
You are here: Downloads / SCN 2.0 - latest

Software/SCN/SCN 2.0 - latest

Download Details

(Sept. 5, 2013)

Latest release of the Klippel Scanning System SCN software.

The tool is free for viewing example scans performed by Klippel GmbH. For performing and viewing own scans a licence will be required.

Please note:
For updating a previous SCN 1.x version a new licence for the scanning is required. Please contact in case you would like to update your purchased SCN 1.x software.

Prerequisites for installing SCN 2.0:
1. Klippel dB-Lab 202.52 or newer
2. Klippel SciEngine 3.1 or newer

Files in this Packet:

Scanning System 2.0.20.exe 13.96 MB
Klippel SciEngine 3.5.exe Klippel Scilab Interface7.48 MB
Manual SCN.pdf 5.15 MB
Example ScanData Most headphone drive units use moving coil technology dispensing with a separate spider and surround. The moving coil assembly is prone to rocking modes, to irregular vibration modes of the wire and the rim zone and to hard limiting at maximal excursion causing Rub & Buzz and other impulsive distortion.

The example scan data shows a very strong rocking motion at 400Hz which is easily visible as peak in the total acceleration level curve, but does not produce more sound pressure level on axis. At 2kHz there is another peak in the acceleration level coming from the next higher circumferential vibration mode.

For headphones the radiated sound power is a good measure to describe the transducer output because the listener is very close to the transducer and covers like that a broad radiation angle range.
6.40 MB
Example ScanData Magnesium One way to use larger drivers higher up in the frequency range is to increase the bending stiffness until the first bending modes are shifted high enough to be out of the intended frequency range of operation.

The first bending mode can be found at 8.4kHz which is due to the light and stiff magnesium cone material. Problematic is the low damping of the material which leads to excessive peaks in acceleration and sound power level. The loss factor of the material can be directly derived from the curve by measuring the 3dB decay width at the peaks.
5.93 MB
Example ScanData Paper Conventional woofers made from paper cone material show good vibration behavior if constructed properly. The decreasing cone curvature from the center to the surround leads to a decrease of bending stiffness. Therefore the cone breaks up starting from the surround and a dominant in-phase vibration component remains located in the center, which shrinks in size at higher frequencies. Thus a woofer with a flexible cone has a smaller directivity index at higher frequencies than a rigid cone.

Imbalances in mass and stiffness distribution on the cone can lead to rocking motion which may cause audible Rub&Buzz distortion at higher cone excursion. The current scan data shows a small tendency to rocking around 375Hz visible in the quadrature vibration component. The difference of more than 20dB to the total acceleration level shows a comfortable distance that Rub&Buzz should not occur.
3.31 MB
Example ScanData Midrange driver with special honeycomb cone structure.

At 6kHz there is strong dip in the sound pressure in axis. The inner and outer cone region vibrate in opposite phase and their produced volume flows cancel out each other. There is a good bending moment propagation between the inner and outer cone due to the stiff honeycomb membrane which leads to this distinct vibration mode.
4.74 MB
Example ScanData Microspeakers are commonly used in mobile devices and reproduce not only speech signals but more and more full band audio signals. Most high frequency drive units use moving coil technology dispensing with a separate spider and surround. The moving coil assembly is prone to rocking modes, to irregular vibration modes of the wire and the rim zone and to hard limiting at maximal excursion causing Rub & Buzz and other impulsive distortion.

The example scan data reveals a rocking motion around 600Hz, which can be best assessed by viewing the Quadrature vibration component. For that small driver bending modes do not occur below 15.5kHz.

The calculation of the effective radiation area SD is of special interest for microspeakers because it is hardly assessable by other means.
6.55 MB
Example ScanData Piston Significant dips in the sound pressure level are caused by acoustical cancellation which occurs if the anti-phase vibration component is not negligible and the difference between in-phase and anti-phase vibration components becomes smaller than 10dB. At the cancellation frequency the in-phase and anti-phase components exchange their location on the radiator\\\'s surface.

Flat driver constructions are especially susceptible to acoustical cancellation problems due to disadvantageous shapes of the low order bending modes. The first acoustical cancellation on the scanned piston driver occurs at 1.1kHz. Though sufficient average cone acceleration there is a strong dip in the sound pressure response on axis. The same effect repeats at 4.4kHz and above.
4.90 MB
Example ScanData Rectangular TV Rectangular speakers are used where the space for placing loudspeakers is limited or a certain non-uniform directivity pattern shall be achieved i.e. in flat television and display devices. For rectangular speakers the vibration patterns are more complex than for circular speakers. Common problems are again rocking modes and acoustical cancellation between cone areas vibration in opposite phase.

The current scan data has been measured with the latest Scanning Software 2.0 which provides several optimizations for scanning rectangular drivers. Especially the definition of a rectangular grid and the application of a sparse grid spacing speed up the scanning process for rectangular speakers.

A rocking of the driver can be seen around 950Hz in the quadrature vibration component. Several higher order
vibration modes produce peaks in the acceleration level of the scan and the resulting sound pressure level is
not as easy to interpret. For rectangular speakers the radiation directivity along the two cone dimensions
can be different and is interesting to analyze.
1.03 MB
Example ScanData The current tweeter material is very soft and has a high damping. Therefore the cone is quickly filled up with higher order bending modes above 7kHz but they do not deteriorate the performance of the sound pressure output because they are so damped.

An interesting vibration mode can be seen around 16kHz which is called a membrane mode. Here no bending motion of the cone but a longitudinal vibration mode inside the cone material shows a resonance and produces a peak in acceleration and sound pressure level.
2.75 MB