200W Amp Module VM 100-K8060 Dampings Faktor Specification

Modules Audio Hi Fi Projects
1

The VM 100 kit specifications are:
damping factor: >800

How is this possible because publication Elektor September 2007 mentiones that the “output resistance at 40Hz” (page 28) of this VM 100 module is 424 milli Ohm. When I do a calculation with a loudspeaker box of 4 Ohm then the damping factor is: 4/0.424=9.4 what is far away from the 800 which the specification of velleman tells us.

Please explain this.

The elektor is to see at:
radio-portal.ru/book/%C6%F3% … 0709Uk.pdf

Regards
John / Lake.

2

Damping has been measured at 100Hz. The data that was recorded at the time of development does not include more details on the exact procedure . We doubt the measurement performed by Elektor is correct. Even our tube-amp has a damping factor of 10 ! :slight_smile: Such a low damping factor is typical for zero feedback amps or tube amps with transformer outputs. The VM100 is none of the previous…